MANUAL OF INSTRUCTION
GUARANTEE:
For a period of one year f r o m date of installation, new e q u i p m e n t manufactured by
UNIVERSAL X-RAY and sold and installed by an authorized UNIVERSAL
X-RAY dealer is guaranteed as f o l l o w s : Any parts proving defective will be
repaired or replaced free of c h a r g e , F.O.B. factory, if defective parts are returned to the
f a c t o r y for inspection, c h a r g e s prepaid. The guarantee does not apply to glassware or
high-voltage cables or to d a m a g e caused by accident, misuse, neglect, or normal wear and
tear, and is void if service is p e r f o r m e d by persons other than authorized UNIVERSAL
dealers or representatives. Components not manufactured by UNIVERSAL X-RAY
are not c o v e r e d by the above, but carry the guarantee of the original
manufacturer. U N I V E R S A L X-RAY reserves the right to pass j u d g m e n t on
cause of breakage or failure.
NOTE: This manual contains information for assemblers and users of a certified p r o d u c t as
required by the Regulations f o r the Administration and Enforcement of the Radiation Control
f o r Health and Safety A c t of 1968 issued by the U.S. Department of Health, Education and
Welfare. This manual is to be delivered to the assembler of the product, w h o , upon
c o m p l e t i o n of installation, is to transmit it to the p r o d u c t user. Any person or persons
responsible for failure to c o m p l y with these instructions shall be liable for resultant d a m a g e s
in a c c o r d a n c e w i t h the law.
Careful attention to all the details and instructions enclosed are necessary for a p r o p e r
installation. Familiarity with the requirements of the DHEW and experience with x-ray
e q u i p m e n t , its installation, use, and maintenance are absolute prerequisites before
attempting any w o r k with these units. Careful attention to the National Electrical c o d e is also
r e q u i r e d . This e q u i p m e n t unless specifically indicated is not designed for use in the
presence of explosive or inflamable gases, and s h o u l d not be installed in flamable
a t m o s p h e r e s . S h o u l d there be any questions, p r o b l e m s , or suggestions either with these
instructions or with the e q u i p m e n t supplied by Universal please write or call U n i v e r s a l X-Ray
4014 W. G r a n d Ave., C h i c a g o , Illinois 60651, 312/276-4487. We will w e l c o m e
any a p p l i c a b l e c o m m e n t s or suggestions.
CHEMETRON
Universal X-Ray
Division of Chemetron Corporation
4014 West Grand Avenue
Chicago, Illinois 60651 U.S.A.
Telephone: (312) 276-4487 .
Cable UNIVAPROCO
#040876
"LITTLE GIANT 30"
a small x-ray unit doing a BIG JOB
Universal X-Ray
Division of Chemetron Corporation
4 0 1 4 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
ELECTRICAL ASSEMBLY, OPERATION, and MAINTENANCE OF X-RAY MACHINE
Cat. No. 3205 "LITTLE GIANT"
TUBEHEAD 30 mA, 95 kVp.
INDEX
section one
Cat. No. 3335 "LITTLE GIANT"
RADIOGRAPHIC CONTROL
30 mA., 95 kVp.
page one
GENERAL DESCRIPTION
page t w o
section two
ASSEMBLY
Dear User:
Y o u r n e w UNIVERSAL x-ray m a c h i n e is a
fine p r o d u c t r e p r e s e n t i n g over 40 years
of e x p e r i e n c e in p r o d u c i n g simple to
o p e r a t e a n d t r o u b l e free e q u i p m e n t .
s e c t i o n three
Read t h i s i n s t r u c t i o n m a n u a l c a r e f u l l y t o
familiarize yourself w i t h the s i m p l e
p c e d u r e s involved in p r o d u c i n g q u a l i t y
r a d i o g r a p h s . Y o u w i l l find that every
r a d i o g r a p h is a r e w a r d i n g e x p e r i e n c e f i l l e d
w i t h interest a n d s a t i s f a c t i o n .
MAINTENANCE
page five
OPERATION
page eight
section four
s e c t i o n five
page ten
MISCELLANEOUS
NOTE: This section contains special
additions and corrections to assembly,
operation and maintenance instructions and
should be consulted before p r o c e e d i n g
with assembly.
We at UNIVERSAL are p r o u d of our
p r o d u c t s and k n o w y o u r x-ray unit w i l l
p r o v i d e many y e a r s of useful and e n j o y a b l e
service. T h a n k y o u f o r s e l e c t i n g o u r
equipment.
This section
provides a means for
expanding the usefulness of this manual by
insertion of newly developed data gained
f r o m field experience and for recording
data d e v e l o p e d by the assembler or user
a p p l i c a b l e to local conditions.
Universal X-Ray P r o d u c t s Inc.
M e r t o n Moss p r e s .
s e c t i o n six
WIRING DIAGRAMS
WIRING D I A G R A M S AND S C H E M A T I C S
R a d i o g r a p h i c c o n t r o l Cat. No. 3335
T w o types of wiring information are
s u p p l i e d . The Wiring Diagram generally
s h o w s 'where the wires go,' and is useful
in physically locating connections f o r
servicing. The schematic diagram s h o w s the
c i r c u i t in a manner which makes it easy to
locate the source of trouble t h r o u g h the use
of logic and d e d u c t i o n . Both types of
d i a g r a m s are supplied for each c o n t r o l /
t u b e h e a d combination c o v e r e d by this
instruction.
s e c t i o n one
GENERAL DESCRIPTION
The Cat. No. 3205 " L i t t l e Giant 3 0 " t u b e h e a d
is d e s i g n e d for use with a variety of
Universal x-ray units identified as f o l l o w s :
Cat. No. 3205 " L i t t l e G i a n t " 30mA tubehead.
Cat. No. 3 1 1 0 - 3 M o b i l e m a s t e r
Cat. No. 3166-3 S c o p e m a s t e r f l u o r o s c o p e ,
Cat. No. 3180-3 Podiatry x-ray, Cat. No.
3175-3 Dentex dental x-ray, Cat. No. 3114
F i e l d m a s t e r portable x-ray for veterinary
use, and the C e p h a l o m e t r i X 3 0 " used for
lateral head and intra oral radiography.
These applications utilizing the " L i t t l e
Giant 30" generator and c o n t r o l , require the
same general procedures d e s c r i b e d in this
booklet under assembly maintenance and
use. Special procedures if any are c o v e r e d
in specific instructions for the model or
a p p l i c a t i o n involved.
page one
Printed In U.S.A.
oioa.74
" L I T T L E GIANT 3 0 "
a small x-ray unit d o i n g a BIG JOB
Universal X-Ray
Power requirements
section t w o
ASSEMBLY
IMPORTANT NOTICE
The x-ray machine s u p p l i e d by Universal
X-Ray P r o d u c t s Inc. and covered in
this manual will p e r f o r m reliably when
o p e r a t e d , maintained, and repaired
in a c c o r d a n c e with the instructions of this
manual. It should be c h e c k e d periodically
and repaired as necessary to insure reliable
operation. B r o k e n , missing, w o r n ,
inaccurate or non-functioning parts should
be replaced. The e q u i p m e n t or its
c o m p o n e n t s should not be m o d i f i e d .
Universal X-Ray P r o d u c t s Inc. cannot assume
responsibility for any malfunction of this
equipment resulting f r o m improper
operation, maintenance or repair, or if any
of its c o m p o n e n t s are d a m a g e d or m o d i f i e d .
Anyone using this x-ray machine must know
and understand the dangers of excessive
radiation exposure. This equipment is sold
with the understanding that since its
proper use and a p p l i c a t i o n is in the hands
of the operator and b e y o n d the control
of the manufacturer or his agents that
Universal X-Ray P r o d . Inc. disclaims all
responsibility for any injury resulting from
i m p r o p e r use and a p p l i c a t i o n of this
equipment.
Unpacking
The shipper is relieved of any responsibility
for d a m a g e during s h i p m e n t after it is
picked up by the carrier.
Examine all cartons carefully at time of
delivery. If d a m a g e is apparent have
delivering driver write a " b a d o r d e r " note
on all copies of the freight bill and sign
it. Should you d i s c o v e r c o n c e a l e d damage,
immediately notify the transportation
agent and ask for an " I n s p e c t i o n Report of
D a m a g e . " Carriers will not accept c o n cealed damage c l a i m s if filed after 15 days
from date of receipt of merchandise.
Open crates and c a r t o n s carefully and do
not dispose of t h e m until you have located
all parts and the m a c h i n e is fully assembled.
Line v o l t a g e r e g u l a t i o n at a maximum rated
line current must not be greater than 5 % .
Percent line voltage r e g u l a t i o n =
100 (Vn Vn
— V I ) where:
Vn = No load line v o l t a g e .
VI = Line voltage at m a x i m u m line current.
A l t e r n a t e line v o l t a g e w h i c h will provide
normal operation are indicated on the wiring
d i a g r a m of the p a r t i c u l a r m o d e l .
M a x i m u m line c u r r e n t at an alternate line
voltage = ( V r ) ( A r ) where:
Vr = Rated line v o l t a g e (no-load).
A r = M a x i m u m line c u r r e n t when line
voltage is equal to the rated line
voltage (no-load).
Va = Alternate line v o l t a g e to be used.
A m p l e power is essential for the efficient
operation of any x-ray machine. To
allow your x-ray machine to be used at full
capacity, the power line to w h i c h y o u r
machine is connected must meet the minimum requirements listed below. If y o u r
power line does not meet these
requirements, you will have limited y o u r use
of the x-ray machine to exposure values
that co me within the limits of y o u r
power line.
Machine, " L i t t l e Giant" 30 mA
Nom, line voltage, 240 volts single phase.
Current rating, 15 amperes.
Sw. box and fuse size, 15 amperes.
Wire size f r o m Power Trans, to sw. box.
50 ft. #12, 100 ft. #10, 200 ft. # 8 .
Machine, " L i t t l e Giant" 30 mA.
Nom. line voltage, 120 volts single phase.
Current rating, 30 amperes.
Sw. box and fuse size, 30 amperes.
Wire size f r o m Power trans, to sw. box.
50 ft. # 1 0 , 1 0 0 ft. #8, 200 ft. # 6 .
Use time lag fuses.
NOTE 1
Maximum daily line voltage variations due
to causes other than the x-ray machine load,
should not exceed ±21/2% of the nominal
line voltage.
NOTE: 2
These recommendations are based on an
overall line voltage regulation not exceeding
5% measured at the x-ray control with the
maximum rated output.
NOTE 3
When operating at reduced line voltages
more line current is required. For e x a m p l e ,
a 208 volt line requires proportionately more
line current than a 240 volt line and may thus
e x c e e d the capacity of the line to stay
within the required Line Voltage Regulation.
The wire size or other factors may limit the
capacity of the line.
Line Current is directly proportional to the
p r o d u c t of kV and mA. and operation at a
lesser p r o d u c t of kV. and mA. will result in
a proportionately lower line current
requirement.
The mA. output can be limited to the
required m a x i m u m in multiples of 5 mA.
from 15 mA. to 30 mA. Use one value of mA.
and establish the mA. presetting value, see
Calibration of Filament Preset on page 4.
See wiring diagram for setting x-ray filament
adjustment (X-FIL ADJ) to a preselected
m a x i m u m of mA. output.
NOTE 4
M a x i m u m Use of Limited Power Line.
Where limited power is available to operate
all the equipment in a facility including
the x-ray unit, it is possible to arrange for
sharing the line.
Certain heavy loads such as air conditioners,
heaters and or sterilizers can be turned off
for the short period of time required to take
an x-ray exposure.
Division of Chemetron Corporation
4 0 1 4 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
ASSEMBLY
Universal x-ray m a c h i n e s are the simplest
possible to assemble and install. Just f o l l o w
the few easy steps given below.
The control is s h i p p e d with a 12 foot line
c o r d and the t u b e h e a d with an 8 foot or
15 foot head to c o n t r o l cable attached to
. the t u b e h e a d and terminating in a 6 wire
polarized Jones plug w h i c h plugs into the
control.
FOR FIXED I N S T A L L A T I O N S
Most state regulations require that " t h e
operator station at the control shall be
behind a protective barrier, either in a s e p a rate room, in a p r o t e c t e d b o o t h , or behind
a shield w h i c h will intercept the useful beam
and any radiation w h i c h has been scattered
only o n c e " and further that "a w i n d o w of
lead equivalent glass equal to that required
by the adjacent barrier, or a mirror system,
shall be p r o v i d e d , large enough and so
placed that the o p e r a t o r can see the patient
without having to leave the protected area
during exposure.
Electrical power must be supplied to a
switch and fuse b o x located in a position
readily accessible f r o m the control l o c a t i o n .
This is a National Electric Code requirement
however, the National Electrical Code
permits " e q u i p m e n t c o n n e c t e d to a 120 volt
branch circuit of 30 a m p e r e s or less (to use)
a g r o u n d i n g type cap and receptacle of
proper r a t i n g — a s a d i s c o n n e c t i n g means"
Thus 30 mA units may be p l u g g eedd into
standard 120 volt wall outlets, if the power
supplied to that outlet satisfy the
requirements listed under the heading
POWER R E Q U I R E M E N T S .
Mobile R a d i o g r a p h i c e q u i p m e n t requires
the o p e r a t o r to make an exposure at a
safe distance and not in the direct b e a m .
Check the local state requirements for
safety regulations w h e n using mobile
x-ray units.
Handle M o b i l e X-ray Units carefully
In order to keep the w e i g h t d o w n to a
m i n i m u m , Universal mobile x-ray units
were d e s i g n e d for careful handling by
capable, authorized operators.
They s h o u l d not be h a n d l e d carelessly or
be b o u n c e d a r o u n d . M o b i l e x-ray units
contain delicate scientific equipment.
They are d e s i g n e d only for interior use on
smooth level floors and unobstructed and
level entrances and exits from rooms and
elevators. The t u b e h e a d should be p l a c e d
in the s e c u r e d position before porting.
(continued
on
next page)
page t w o
R0A0776
R031777
"LITTLE GIANT 3 0 "
a small x-ray unit d o i n g a BIG J O B
Universal X-Ray
Division of Chemetron Corporation
4014 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
section two
ASSEMBLY
Frequently c h e c k all locks, wheels, bolts,
nuts, etc. and the entire unit to be sure
nothing was d a m a g e d , knocked off or
shaken loose d u r i n g moving and h a n d l i n g .
DO NOT OPERATE E Q UIPM ENT until
a c c e p t a b l e c o r r e c t i o n s are made.
With frequent inspections and p r o p e r care
this unit will provide continuous useful
service.
A T T A C H I N G T U B E H E A D TO SUPPORT
STRUCTURE
Attach the t u b e h e a d to its support by
inserting the yoke pivot shaft into the
support receptacle and securing by
tightening the locking screw in the support.
This applies to the 30 mA mobile x-ray unit
Cat. No. 3110) and other Universal
supporting structures w h i c h secure the
fork in a horizontal position.
When the fork of the t u b e h e a d is inserted
in a s u p p o r t i n g structure receptacle so that
it hangs vertically such as the Cat. No. 3180
Podiatry x-ray unit, then care should be
taken so that the t w o special screws w h i c h
secure the w a s h e r to the stud of the fork
are w i r e d in with the wire p r o v i d e d . The two
special screws have holes for this wire.
See assembly instructions included with the
supporting structure.
ATTACHING COLLIMATOR
TO T U B E H E A D
A suitable c o l l i m a t o r must be used with the
30 mA t u b e h e a d s . T h e tubehead cover has
a port thru w h i c h the primary x-ray beam
is e m i t t e d , and s u r r o u n d i n g the port are
f our holes for a t t a c h m e n t of the collimator.
A t t a c h m e n t bolts are s u p p l i e d . Check them
out f o r p r o p e r fit.
"emove the cover from the tu b e h e a d by
amoving the seven s c r e w s which attach the
c o v e r to the t u b e h e a d , and lifting off the
cover. Secure the c o l l i m a t o r to the cover
with the bolts s u p p l i e d and tighten bolts
well. Be sure c o l l i m a t o r front is in the same
d i r e c t i o n on the c o v e r as the front of the
t u b e h e a d . Be careful that the bolts used
do not project too far inside the cover since
this may cause p u n c t u r e of the expansion
bag. C h e c k carefully and insert a fiber or
rubber barrier if necessary to protect
e x p a n s i o n bag. Put heads of screws inside
c o v e r if possible.
Replace cover on t u b e h e a d with cover
attachment s c r e w s .
ADJUSTING THE CONTROL
TO LINE VOLTAGE
HOW TO CHECK FOR CORRECT
LINE V O L T A G E SETTING
The control line c o r d is normally tagged
indicating the line voltage at w h c h it is
set. It usually is set at 230 volts. This
reduces possibility of damage to the
control which w o u l d o c c u r if the control
were set at 120 volts and accidentally
connected to a 230 volt line.
If a v o l t m e t e r for checking the line is not
available then the control kVp meter, w h i c h
is a voltmeter can be used.
This adjustment should be made with the
line c o r d disconnected from the s o u r c e . For
c h e c k i n g purposes the t u b e h e a d plug can
be d i s c o n n e c t e d from the c o n t r o l .
Check the setting inside the control to be
sure it corresponds with the indication on
the tag. If used on a different voltage than
on the tag, change voltage on tag or
remove tag.
With the control selector knob pointing to
" V " on the panel and the main switch in the
" O N " position, the top scale (preset volt
scale) on the voltmeter s h o u l d read
a p p r o x i m a t e l y 117 volts. This 117 volt
position on the meter is identified by the
letter " V . "
To check or reset the line voltage inside the
control, disconnect the cable from the
power outlet. Place the control upside down
on a solid table using a folded towel or
blanket for padding to protect the control
panel. Remove the two screws at the lower
end of the sides of the control and lift the
back panel out at the lower end and pull
down away from the pins at the upper end
of the control housing. Exercise care so that
the interior wiring is never disturbed or
damaged.
The control terminal board is marked with
numbers 9 thru 14. Using the chart below
(also chart on wiring diagram on inside of
back of control), connect the leads marked
Lj and L to the terminals on the terminal
board in the control corresponding to the
line voltage (power source).
2
E X A M P L E : For a 118 volt line connect L1
to terminal 1 and L to terminal 12. Choose
the terminals corresponding to a voltage
closest to the actual line voltage.
2
LINE
VOLTS
97
104
110
117
123
130
205
211
217
224
230
237
243
250
CONNECT
L1 to
1
1
1
1
1
1
0/S1
0/S1
0/S1
0/S1
0/S1
0/31
0/S1
0/S1
The c o l l i m a t o r normally requires 24 volts
for the light bulb. C h e c k the instructions
s u p p l i e d with the c o l l i m a t o r for details on
mounting and voltage and wattage
requirements. Universal controls Cat. No.
3335 provide a 24 volt, 200 watt source at
terminals C1 and C2. Consult wiring
diagram.
Bring the wire in t h r u the bottom of the
control alongside the e x p o s u r e pushbutton
cable and c l a m p securely.
page three
CONNECT
L2 to
9
10
11
12
13
14
7
8
9
10
11
12
13
14
HOW TO SET KILOVOLTS
Always set kilovolts before you turn on
x-rays,never turn the kilovolt selector knob
while the exposure switch is closed and
x-rays are on.
Turn on the main switch. Determine the
required exposure factors you are going
to use.
For e x a m p l e — s u p p o s e you are going to
use 15 mA and 80 kVp. Turn the kilovolt
selector until the kilovoltmeter needle
points to 80 on the 15 mA scale. If you
cannot set the needle exactly on 80, then
set it slightly above 80 rather than below.
Since each step of the kilovolt selector
changes kilovoltage by a p p r o x i m a t e l y
3 kVp, you can always set kilovoltage
sufficiently close to the desired value.
If you use a value of mA not s h o w n on the
kilovoltmeter then approximate the position
between the higher and lower mA lines
and thus you will come fairly close to the
c o r r e c t kVp.
Low p o w e r e d units are s o m e t i m e s o p e r a t e d
on the same circuit with other e q u i p m e n t
and may be subject to voltage d r o p . T h i s
should be considered in establishing
exposure values.
"LITTLE GIANT 30"
a small x-ray unit doing a BIG JOB
Universal X-Ray
Division of Chemetron Corporation
4 0 1 4 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
section t w o
ASSEMBLY
AUTO TRANSFORMER VOLTAGE TABLES
The voltages indicated in the tables shown
will only be obtained if the line voltage has
one of the indicated discrete values, and
the line voltage tap is properly set. Since
line voltage will probably vary a volt or so
from one of the indicated values, all
readings will be off by the same percentage.
Ep Volts is the voltage between 1 AT or X2
and the selector switch w h i c h goes thru
the contactor to X 1 . These are the voltages
delivered to the primary of the hi-tension
transformer.
The Ep VOLTS can be read on the top (red)
scale of the kilovoltmeter.
Obtain preset reading for all values of mA.
shown on the voltmeter.
Make a table showing preset values
as f o l l o w s :
MA.
KV KNOB S E T T I N G
M
No Load 1 P r i m a r y Ep V o l t s 6 0
Load Pri. Volts
59
at
5 mA. kVp. (kilovolts)
45
N
0
65
71
65
70.5
52
56
P
Q
R
S
T
U
V
W
X
77
83
88
95
102
108
115
123
129
76
82
88
94.5
101
127
65
71
76
81
75
81
87
93
60
107.5
114
120.5
87
91
96
101
106
112
118.5
124.5
Load Pri. Volts
58
at
1 5 mA. k V p . ( k i l o v o l t s ) 40
63.5
44
50
55
60
64
69
74
80
85
92
Load Pri. Volts
57
at
2 0 mA. k V p . ( k i l o v o l t s ) 32
62.5
68.0
73.5
80
86
92
98
105
111
117
39
44
48
53
59
64
71
76
80
85
Load Pri. Volts
56.5
at
2 5 m A . k V p . ( k i l o v o l t s ) 28
62.5
68
73.5
79
85
91
98
104
109.5
116
Load Pri. Volts
56
at
3 0 mA. k V p . ( k i l o v o l t s ) 24
69
34
38
44
50
54
59
62
67.5
73
78.5
84 . 5
90.5
30
35
40
45
50
55
(continued
M A X I M U M M I L L I A M P E R E LIMIT SET
Remove the rear panel from the control for
access to the X-Fil limiting resistor. (Section
4). With the milliampere selector fully
clockwise, set control panel mA. selector
knob to L position, move the band on this
resistor to deliver about 32 to 33 mA. at
60 kVp. and tighten band locking screw.
On the Cat. No. 3334 Fluoroscopic only
control, position the band to restrict the
fluoroscopic mA. to the maximum legal
limit with the milliampere selector set
fully clockwise.
Under the Federal Performance Standards
" F l u o r o s c o p i c equipment which
is not provided with automatic exposure
rate control, shall not be operable at any
combination of tube potential and current,
which will result in an exposure rate in
excess of 5 roentgens per minute at the
point where the center of the useful beam
enters the patient." etc. etc. Measurements
should be made 1 c M . away from the
fluoroscopic panel thru which the radiation
passes before entering the patient or
subject.
CALIBRATION OF THE FILAMENT PRESET
Since the milliammeter only reads DURING
an exposure, it is necessary to provide the
operator with a preset calibration so that
he may preset milliamperes before the
exposure begins. Once these preset values
are obtained it is not necessary to make
test exposures before every radiograph is
taken, in order to set the control to deliver
the desired value of milliamperes. Periodic
checks should be made to insure that
some degree of a c c u r a c y is maintained.
Two different methods are simultaneously
available to preset milliamperes.
a. Reading the position of the milliampere
selector knob and,
b. pressing down the "Filament Preset
S w i t c h " and reading the "Preset V o l t s "
scale on the voUmeter.
99.5
65
96.5
60
from
71
76
80
103
109
115.5
72
76
65
preceding
Milliampere
Selector
Preset Volts
96
123
91
122
85
121.5
81
column)
For accuracy of mA. presetting
the preset voltmeter reading
method should be used.
Here is how to calibrate the filament preset.
1. Turn on the main switch on control and
set kilovoltage control knob for an
average value of kVp. that will be used
most frequently (See sheet on exposure
technique). About 80 pKv. is a g o o d
average setting.
2. Assume that a reset value for 15
milliamperes is to be obtained. Set the
timer for approximately two seconds and
make an exposure using one hand on the
milliampere selector knob to gradually
(but quickly) bring up the reading on the
mA. meter to the desired 15 mA.
Care must be exercised to make these
presettings accurate. When the timer button
is pressed during an exposure, watch the
milliampere meter needle. If it falls below
the requirements this may be compensated
for q u i c k l y by advancing the control during
the exposure. Some corrections of preset
values may have to be made from time to
time because of changing filament
characteristics. Some variation in
milliamperes can also be caused by line
fluctuations during exposure and cannot be
c o r r e c t e d by changing preset values.
FOR REVISED PANEL LAYOUT INTRODUCED
APRIL, 1979 SEE PAGE 1 1 .
HOW TO A L I G N THE C O L L I M A T O R
It is a legal requirement that the collimator
light beam be aligned with the x-ray beam so
that misalignment in either direction does
not e x c e e d 2% of the source image
receptor distance (SID). For instance, if the
source image receptor distance (SID) is
37 /2 inches, the maximum allowable
misalignment is 2% of 37 /2 = 3/4 inches.
1
1
NOTE: Exposures under 7 / 1 0 seconds will
not permit the milliampere needle to reach
the c o r r e c t value of mA. Be sure test
readings are taken at the point w h e r e the
needle comes to a momentary rest. When
making an exposure below 7 / 1 0 seconds
the needle will swing past or fall short of the
actual mA. passing thru the tube and
therefore it is necessary to use the preestablished setting of the mA. control knob.
Since the c o l l i m a t o r is packed separately it
must be aligned at installation.
Refer to the instruction sheet packed with
the c o l l i m a t o r for location of adjustments
and information on how to make the
adjustments.
C A U T I O N : Do not exceed tube rating chart
in making test exposures. Be sure that tube
port is not directed at operator or loaded
cassette or film since x-rays are being
p r o d u c e d during testing.
Hold down the "filament p r e s e t " switch and
accurately read and record the preset volts
reading on the top scale of the pKv. meter.
Record the position of the milliampere
selector knob (Example A5 or B6.5 etc.)
In o r d e r to again obtain this value of
milliamperes it will not be necessary to
make an exposure. Merely set the
milliampere selector knob to this
predetermined position on the voltmeter.
(continued
page four
on
next
page)
"LITTLE GIANT 3 0 "
a small x-ray unit d o i n g a BIG JOB
Universal X-Ray
Division of Chemetron Corporation
4 0 1 4 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
s e c t i o n three
OPERATION
Protective Measures
X-ray e q u i p m e n t i m p r o p e r l y used may cause
injury. All persons using this equipment
must be familiar with the hazards involved
and the necessary protective measures
before using the e q u i p m e n t . This equipment
must be operated only by informed c o m petent personnel. Even tho this equipment
has built in p r o t e c t i o n against all radiation
except the useful b e a m , no practical
design can provide c o m p l e t e protection or
c o m p e l the o p e r a t o r or his assistant to take
adequate precautions to prevent the
possibility of authorized or unauthorized
persons, carelessly, unwisely, or
unknowingly exposing themselves or others
to direct or s e c o n d a r y radiation. Handbooks
n Radiation Protection have been c o m p i l e d
by the National C o m m i t t e e on Radiation
P r o t e c t i o n and are available from NCRP
Publications, B o x 4867, Washington, D.C.
20008. The o p e r a t o r must become familiar
with and use this e q u i p m e n t as recomm e n d e d in these h a n d b o o k s .
M A I N LINE SWITCH
This equipment is sold with the understanding that since Universal X-Ray Products Inc. has no control over the way the
equipment is used, Universal X-Ray
P r o d u c t s Inc., its agents or representative
cannot assume responsibility for injuries
suffered by anyone thru the use of this
equipment.
All personnel must be protected from the
useful beam and also f r o m the secondary
x-rays that are produced whenever x-ray
strikes any project.
Various protective materials and devices
are available. It is urged that such materials
or devices be used.
The main line switch is a c o m b i n a t i o n line
switch and overload breaker. It is " T r i p
F r e e , " that is, you cannot hold it c l o s e d if
there is a short circuit or o v e r l o a d .
LINE ON Pilot Light
Ruby light indicates that the main switch
is in the ON position.
No e x p o s u r e can be made unless the key
lock e x p o s u r e switch is in the ON position.
The key cannot be removed in this position.
The key lock exposure switch will not turn
off the ruby light. It will only go off w h e n
the main switch is in the OFF position.
To keep this equipment properly calibrated,
it must be electrically and mechanically
inspected and c h e c k e d in a c c o r d a n c e with
Maintenance Procedures listed in Section 4
of this instruction manual, at regular
intervals of 1 year or less, depending on the
age and amount of use the equipment
receives. If trouble o c c u r s — c a l l your serviceman and do not operate the equipment
until the repairs are c o m p l e t e d and c h e c k e d
out.
CHART FOR OBTAINING THE ACTUAL VALUES OF KILOVOLTAGE UNDER LOAD AT A PARTICULAR MILLIAMPERE (MA.) SETTING.
KV KNOB SETTING
N o L o a dd P r i m a r y
Load
at
kVp.
5 mA.
Lead
Pri.
Amps.
Pri.
Load
Pri.
at
kVp.
20 mA.
Lead
Load
at
kVp.
25 mA.
Lead
Load
at
kVp.
30 mA.
Lead
Volts
(kilovolts)
Load
at
kVp.
15 mA.
Lead
N
0
P
60
65
71
77
83
59
65
70.5
76
82
45
52
56
2.9
2.9
2.9
M
Volts
Volts
60
Q
65
S
R
88
94.5
95
94.5
71
76
3.0
3.0
3.0
3.1
T
U
102
108
115
123
129
101 107.5
114
120.5
127
V
w
X
81
87
91
96
101
3.1
3.1
3.1
3.1
3.2
106
112
118.5
124 .5
80
85
58
63.5
69
75
81
87
93
99.5
(kilovolts)
40
44
50
55
60
64
69
74
Amps.
8.7
9.0
9.2
9.0
9.0
9.0
9.0
9.0
9.0
9.2
9.2
9.5
57
62.5
68.0
73.5
80
86
92
98
105
111
117
123
(kilovolts)
32
39
44
48
53
59
64
71
76
80
85
91
Amps.
11.6
11.6
11.6
11.5
11.6
11.6
11.6
11.6
11.6
11.6
11.6
11.6
56.5
62.5
68
73.5
79
85
91
98
104
109.5
116
122
X1
Pri.
Volts
Volts
92
96
(kilovolts)
28
34
38
44
50
54
59
65
71
76
80
85
Amps.
14.2
14.2
14.1
14.2
14.2
14.2
14.2
14.1
14.1
14.1
14.1
14.2
115.5
121.5
X1
Pri.
Volts
56
62
67.5
73
78.5
84.5
90.5
96.5
103
109
(kilovolts)
24
30
35
40
45
50
55
60
65
72
76
81
Amps.
17
17
17
17
16.8
16.8
16.8
16.9
17
16.5
16.9
16.8
X1
This chart provides the actual
draw in the primary of the high
tension transformer
lead at
the various settings of milliamperes.
This primary current
will vary directly with the milliamperes and therefore be sure
to check the accuracy of the
mA. meter reading to establish
the validity of any current
measurements.
The X1 current can be obtained
using a clip o- ammeter.
It
will detect a short in the primary or secondary coils or a
defective inverse suppressor.
(See page 10 on checking the
inverse suppressor.)
page five
010274
REV. 5-20-75
8-7-76
"LITTLE GIANT 3 0 "
a small unit doing a BIG J O B
Universal X-Ray
Division of Chemetron Corporation
4014 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
section three
OPERATION
READY PILOT
HOW TO OPERATE THE M A C H I N E
THE M I L L I A M M E T E R
indicates that the line switch is turned on
and that the machine is ready for operation.
Universal X-ray machines are d e s i g n e d to
be extremely simple to operate and all you
have to do is to follow the few simple steps
given below. However, before y o u operate
this or any other x-ray machine, you must
b e c o m e familiar with all of the necessary
protective measures and also R a d i o g r a p h i c
Technique.
A single scale meter w h i c h reads directly
in milliamperes. It indicates only during the
exposure when current is flowing thru the
x-ray tube and thus also serves as an
"X-Ray O n " indicator.
HOW TO SET TIME
The timer on the Cat. No. 3335 control is a
Radiographic timer with a time range to
6 seconds in 21 steps, and in approximate
geometric progression.
Rotate the timer selector knob to bring the
desired time value under the pointer.
An exposure thru the timer is made by
depressing the exposure switch on the
control and holding it d o w n until the timer
turns off the exposure. Releasing the button
will instantly terminate the exposure
irrespective of the timer setting.
Determine the technical factors (kV., mA.
and time) you are going to use, then
p r o c e e d as f o l l o w s :
HOW TO TURN ON THE M A C H I N E
Push the LINE SWITCH lever to the " O N "
position. The kilovoltmeter will i m m e d i a t e l y
indicate and the READY PILOT will light.
HOW TO USE THE C O L L I M A T O R
REMOTE EXPOSURE SWITCH A single
c i r c u i t 2 wire Cat. No. A979 hand switch or
Cat. No. 3508 foot switch can be connected
to terminals S1 and S2.
The c o l l i m a t o r contains a lamp and m i r r o r
system w h i c h :
THE KILOVOLT SELECTOR
b. Casts s h a d o w s of cross-lines s h o w i n g
the center line of the x-ray b e a m in t w o
directions.
The kilovolt selector is a 12 position switch.
Turn the selector knobs to the right
(clockwise) to increase kilovoltage. Never
t u r n the kilovolt selector d u r i n g an x-ray
e x p o s u r e . The kilovolt selector must always
be adjusted to the desired kilovolts before
starting the x-ray e x p o s u r e .
a. Projects a light beam covering the same
area as the x-ray beam.
This permits easier and more a c c u r a t e
positioning of the patient and at the same
time permits adjustment of the x-ray beam
size to the size of the film being used,
reducing both secondary radiation and
patient dosage.
THE KEY LOCK EXPOSURE SWITCH.
The key lock exposure switch on the panel
of the control prevents an exposure to be
made when the key is removed from the
switch. It does not prevent the main s w i t c h
f r o m being left o n . Be sure the MAIN
SWITCH is turned off when the x-ray
machine is not in use.
Adjust the c o l l i m a t o r to deliver an x-ray
beam the same size as the film being used
and at the distance being used. Use the
c o l l i m a t o r light beam to position the patient
so that the desired area is e x p o s e d . DO
NOT leave the light beam on any longer than
is necessary because the high intensity lamp
has a short operating life.
An audible signal in the f o r m of a single
" b o n g " of a bell in the control will indicate
the termination of an exp o su r e .
Check instructions supplied with the
c o l l i m a t o r for any more details.
THE KILOVOLTMETER
A l w a y s set kilovolts before you turn on
x-rays never turn the kilovolt selector knob
while the exposure switch is c l o s e d and
x-rays are on.
The kilovoltmeter is an ac voltmeter,
calibrated in kilovolts. It also has a line
marked 'V' w h i c h is used to c h e c k for proper
line voltage adjustment.
See kVp chart page four
HOW TO SET KILOVOLTS
Turn on the main line switch. Consult the
exposure technique chart to determine the
required exposure factors. For e x a m p l e : If
the t e c h n i q u e chart requires 15 mA. and
80 kVp., turn the kilovolt selector until the
kilovolt meter needle points to 80 on the
15 mA. scale. If you cannot set the needle
exactly on 80, set it slightly above 80 rather
than below. Since each step of the kilovolt
selector changes kilovoltage by
a p p r o x i m a t e l y 3 kVp., you can always set
kilovoltage sufficiently close to the d e s i r e d
value.
page six
The o p e r a t o r s h o u l d always observe the
milliameter d u r i n g exposure in order to be
sure that a n o r m a l exposure has been made.
Observing this meter during exposure makes
it possible for the o p e r a t o r to act quickly
in turning off the main switch in the event
failure of some c o m p o n e n t should o c c u r
due to age or line conditions. Failure may
manifest itself by a continuation of the
exposure beyond the normal estimated time
setting, or a wide fluxuation in the mA
meter reading.
On very short fractional exposures the
mA. meter reading may fall short or swing
past the actual mA setting. See the
paragraph " H o w to make an x-ray
e x p o s u r e " for more details.
THE M I L L I A M P E R E SELECTOR
The Milliampere Selector is directly below
the Milliammeter. This is a stepless control.
Turn the selector knob to the right to
increase milliamperes but remember that
the milliammeter only reads d u r i n g an
e x p o s u r e (unlike the kilovoltmeter w h i c h
reads all the time that the line switch is on).
THE PRESET SWITCH
Press the preset switch lever down to
connect the kilovoltmeter to read x-ray
filament t r a n s f o r m e r primary volts on the
top meter scale (preset volts scale). Release
the preset switch lever and it automatically
reconnects the kilovoltmeter to indicate
kilovolts.
HOW TO SET M I L L I A M P E R E S
Milliamperes can be preset
by turning the miiliampere selector
to a p r e d e t e r m i n e d position on its scale
by using the kilovoltmeter preset scale. If
you have an unusually stable power line,
you might be able to use the miiliampere
selector scale to preset milliamperes, but
Universal X-Ray Products, Inc., recommends
using the kilovoltmeter preset scale. To
preset m i l l i a m p e r e s to the desired value by
this m e t h o d , p r o c e e d as f ol low s :
Refer to the table of preset volts versus mA.
prepared when the machine was first
installed (See Section 2 Calibration of the
Filament Preset) and determine the preset
volts c o r r e s p o n d i n g to the value of mA. you
wish to use. Press d o w n on the preset
switch handle, and turn the Miiliampere
Selector Knob until the Kilovoltmeter needle
points to the desired value of preset volts.
Release the preset switch handle.
"LITTLE GIANT 3 0 "
a small unit doing a BIG JOB
Universal X-Ray
Division of Chemetron Corporation
4014 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
section three
OPERATION
HOW TO M A K E AN X-RAY EXPOSURE
C A U T I O N : The milliampere meter is an
indicator of x-ray being p r o d u c e d . If it
should continue to read b e y o n d the time set
on the timer, then quickly turn off the main
switch and do not operate the e q u i p m e n t
until c h e c k e d out and c o r r e c t e d .
Set the timer to the desired value of time.
Press the exposure button on the control.
An approved handswitch or footswitch can
be connected to terminals S1 and S2 in the
control to also operate the exposure circuit.
Observe the m i l l i a m m e t e r during the
exposure. The milliammeter should indicate
the value of mA. used, except that for short
exposures, the needle may not have time to
swing up and read the c o r r e c t value.
On very short e x p o s u r e s the needle may
swing past or fall short of the actual mA.
setting. On exposures of about 1/2 second
and higher the needle may swing past the
-tual setting and momentarily come back
rest at the actual mA. before dropping
back to zero at the end of the exposure.
This needle response is not to be construed
as an indication of the actual mA. being
higher or lower or c o m i n g up slowly. It is
only the inertia of the meter that causes the
needle to swing past the actual value.
HOW TO TURN OFF THE M A C H I N E
When you are thru using the machine push
the LINE SWITCH lever to the ' o f f position.
Never leave the control switch in the on
position when not in use since this will
shorten the life of the x-ray tube.
N O T E : The exposure lock switch does not
turn off the machine. It only locks the
exposure circuit so that no exposure can
be made when the key is removed.
P O D I A T R Y - O T H E R APPLICATIONS
Podiatry and other radiographic or fluoros c o p i c a p p l i c a t i o n s utilizing the " L i t t l e
Giant 3 0 " generator and c o n t r o l , require the
same general p r o c e d u r e s described in this
b o o k l e t under assembly maintenance and
use. Special p r o c e d u r e s if any are covered
in specific instructions for the model or
a p p l i c a t i o n involved.
USE OF GRIDS WITH " L I T T L E GIANT 3 0 "
On heavier, denser subject matter the use of
a g r i d (by placing the cassette in the
cassette tray in the grid cabinet) is desirable
in o r d e r to reduce the amount of scatter
radiation w h i c h tends to fog the film. An 8:1
ratio grid will p r o d u c e the best results.
The " L i t t l e Giant 3 0 " generator will p r o d u c e
a m a x i m u m of 30 milliamperes. On ordinary
115 volt lines (plug in receptacles) the
m a x i m u m obtainable may be limited to
a p p r o x i m a t e l y 15 or 20 milliamperes.
page seven
SUGGESTED TECHNIQUE FOR
30 M A . UNITS
V e r y little difficulty in t a k i n g consistently g o o d r a d i o g r a p h s w i l l
be e x p e r i e n c e d if the user w i l l observe some s i m p l e rules and u s e
the f o l l o w i n g suggested techniques as a starting point. Variations
to suit i n d i v i d u a l r e q u i r e m e n t s may be m a d e .
DARKROOM
1.
Use fresh solution. Change r e g u l a r l y based on the s i z e
of tank, n u m b e r of films processed, and age of solut i o n . For average office using 5 g a l l o n tank change
solution e v e r y three to f o u r w e e k s .
2.
Use fresh f i l m , p r o p e r l y s t o r e d , and h a n d l e d w i t h
p r o p e r filter and r e c o m m e n d e d b u l b size in d a r k r o o m
l a m p . Keep film as far a w a y f r o m d a r k r o o m lamp as
possible.
CASSETTE SCREENS
Use g o o d cassette and screens. Exposures g i v e n are
based on the use of high speed screens.
DISTANCE OVER FILM
Use 40" distance f r o m top of table to tube ( w h i t e dot on
f r o n t of tube) for ail over table and bucky or g r i d cabinet
r a d i o g r a p h s , A convenient m e t h o d is to put a mark on the
vertical c o l u m n , (a grease pencil line or a piece of tape)
Use 7 2 " distance for chests and lateral cervicals. Measure
f r o m the cassette holder to the t u b e , put a mark on the table
i d e n t i f y i n g this position.
Variations in subject density can be corrected by v a r y i n g the
e x p o s u r e t i m e (staying w i t h i n tube ratings). If films are too dark
reduce t i m e , if too light increase time. This assumes that f i l m
d e v e l o p i n g t i m e remains fixed and is v a r i e d o n l y to compensate
for variations in t e m p e r a t u r e of solution.
EXTREMITIES - hands, w r i s t , ankle, e l b o w , etc.
MILLIAMPERES 15 m a .
KILOVOLTAGE " U " setting for all exposures (75 t o 8 0 pkv.)
TIME
1 second
using nonscreen f i l m in paper f o l d e r or
nonscreen m o n o p a c k , five m i n u t e d e v e l o p i n g r e q u i r e d
w i t h nonscreen f i l m . For Regular f i l m in cassette w i t h
Universal X-Ray
high speed
second
film
u s e a p p r o x i m a t e l y 1/10
to
1/2
CHEST
DISTANCE - 7 2 "
CASSETTE w i t h screens
MILLIAMPERES —
15
selector k n o b
ma.
Record
p o s i t i o n of
milliampere
KILOVOLTAGE - " U " setting ( a p p r o x i m a t e l y 8 0 p k v . )
TIME - 1 / 2 t o 7 / 1 0 second
CERVICAL SPINE
Lateral o r P.A... u s i n g 7 2 " d i s t a n c e w i t h 8 x 1 0 c a s s e t t e i n adjustable w a l l cassette holder.
MILLIAMPERES 15 M a .
KILOVOLTAGE - " U " setting ( a p p r o x i m a t e l y 8 0 pkv.)
TIME - 1 second
SKULL, SINUS, CERVICAL SPINE, KNEES, SHOULDER
CASSETTE w i t h screens
KILOVOLTAGE - " U " setting ( a p p r o x i m a t e l y 7 5 t o 8 0 p k v . )
MILLIAMPERES —
1 5 ma. R e c o r d p o s i t i o n o f m i l l i a m p e r e
selector k n o b
TIME
a p p r o x i m a t e l y 2 seconds
(knee a n d shoulder
1 / 2 s e c o n d , s h o u l d e r t h r u b o d y 2 second)
Time g i v e n b a s e d o n use w i t h 8 0 l i n e 8 : 1 f i x e d g r i d i n g r i d cabinet.
Use a p p r o x i m a t e l y 3 5 % m o r e t i m e f o r exposures w i t h b u c k y . The
stationary g r i d in a g r i d cabinet is r e c o m m e n d e d .
PELVIS, HIP, LUMBAR SPINE, GASTRO INTESTINAL
MILLIAMPERES —
knob
1 5 ma. R e c o r d p o s i t i o n o f m a .
selector
KILOVOLTAGE - " U " setting ( 7 5 t o 8 0 p k v . )
TIME — A.P. V i e w —
3 seconds
WITHOUT GRID - 1 - 1 / 2 seconds
Time g i v e n based o n use w i t h 8 0 line 8 : 1 f i x e d g r i d i n g r i d cabinet.
Use a p p r o x i m a t e l y 3 5 % m o r e t i m e f o r exposures w i t h b u c k y . The
stationary g r i d in a g r i d cabinet is r e c o m m e n d e d .
4014 West Grand Avenue
Chicago. Illinois 60651 U.S.A.
Universal X-Ray
"LITTLE GIANT 30"
a small unit doing a BIG JOB
Division of Chemetron Corporation
4014 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
section four
section three
MAINTENANCE
OPERATION
FOCAL SPOT RATINGS
Note that these ratings apply to a cold tube.
Never apply more than 7 0 % of these ratings
after the tube has been heated up thru use.
Effective focal spot size; 2.0mm.
Effective target angle; 20 degrees
TROUBLE SHOOTING
The kilovolt meter in the control is an ac
voltmeter and the preset scale is calibrated
in ac volts. If you have no other meter
available, in an emergency you can
disconnect and tape up the leads going to
the kilovoltmeter and use the kilovoltmeter
for trouble shooting. Be sure to reconnect
the leads when you are finished.
NO KILOVOLTMETER READING
If there is no kilovoltmeter reading when the
main switch is " O N " make the following
checks:
1. Check line supply. Disconnect switch
may be open or fuses blown. If line
supply is OK.
ANODE HEAT STORAGE RATINGS
Max. Cooling rate; 350 H.U./sec.
Max. Anode Heat Storage capacity:
70,000 H.U.
The anode heat storage rating of x-ray
tubes used in the Cat. No. 3205 30 mA.
tubeheads is 70,000 heat units. To determine
the number of heat units you will put into
the anode, multiply kVp. X mA. X seconds.
Thus technique w h i c h calls for 80 kVp.,
30 mA. and 1 1/2 econds, produces
80 X 30 X 1 1/2 = 3 6 0 0 heat units.
Fluoroscoping at 80 kVp. and 5 mA.
produces 80 X 5 X 60 seconds = 24,000
heat units a minute.
TUBEHEAD HEAT STORAGE CAPACITY
HEATING—With x-ray apparatus, most of
the electrical energy developed in the high
tension transformer and delivered to the
tube is converted into heat. This conversion
takes place at the focal spot on the target.
The quantity of heat that is generated is
proportional to the mA., and the pKv. and
the time of exposure. At 15 mA., heat is
generated at a m u c h higher rate than is
conducted away f r o m the focal spot. It is
therefore, important to limit the length of
exposures at the higher mA. values within
the limits of the tube rating chart.
There is also the general temperature of the
unit to be considered. After the unit has
been run for a series of exposures, it may
be found that the x-ray head is warm. The
transformer, tube and oil will be warmer
than the x-ray head. It is safe to keep using
the equipment when the head is slightly
warm, but extreme care must be taken not
to exceed the limits per exposure
for radiography either when the x-ray head
is warm o r c o o l .
Misuse of the x-ray tube through exceeding
the safe exposure limits may melt the
target and, of course, ruin the tube.
30 mA. TUBEHEAD OIL HEAT
STORAGE CAPACITY
1. Oil capacity—approximately 5620
milliliters at 20ºC.
2. Check to see if line cable is properly
plugged in (or line disconnect switch
closed).
3. Be sure kilovolt selector is not set
between contacts but is properly indexed
on a contact point.
2. Oil expansion bag at 20°C is normally
filled with approximately 100 milliliters
of oil.
4. Check kilovoltmeter so that it is not open
circuited or stuck.
3. Expansion bag total capacity (fully
expanded) approximately 400
milliliters.
NO MILLIAMMETER READING
4. Raising oil temperature in tubehead from
2 0 ° C to 95°C will add 300 milliliters of
oil to expansion bag, thus making a total
of 400 milliliters oil (maximum it will
hold).
5. Lowering the oil temperature from 20°C
to-5°C will empty bag.
Circulated maximum operating temperature
— 5 ° C t o 95°C.
Suggested maximum operating
temperatures + 5°C to 8 0 C
( 4 1 ° F t o 170°F).
C
DUTY CYCLE
There is no cycle limitation on any of the
control units listed herein.
The tubehead duty cycle is determined for
high energy short time exposures by the
ratings of the x-ray tube and for low energy
long time operation by the oil expansion
capacity of the tubehead.
TUBEHEAD RATINGS
M a x i m u m rated peak tube potential 95kVp.
M a x i m u m mA rating 30 milliameters.
Leakage technique factors 95kVp, 2 mA.
M i n i m u m inherent filtration with no added
filter is 1.5 mm. aluminum at 90 kVp.
page eight
No exposure can be made unless the key
lock exposure switch is in the ON position.
The key cannot be removed in this position.
X-Rays are turned on by timer or f o o t s w i t c h .
1. See if x-ray tube filament lights up. Do
not make any exposure during this test.
The tube is visible thru clear plastic
window. Tubehead covers will need to be
removed. Another check is to remove
cover and put a voltmeter between
terminals F1 and F2. If no voltage
reading is obtained the trouble is
possibly in head-to-control cable, control
or line. If there is a voltage reading, the
trouble is in t u b e h e a d , possibly a
burned out filament.
2. Make sure the timer or footswitch is
operating properly. This can be
established by removing the head cover
and checking to see if a voltage is
obtained by means of a voltmeter or a
test lamp connected between leads
X1 and X2. If no voltage is obtained c h e c k
back, starting with the timer (see wiring
diagram). Be sure to cover port of tube
and cover back on tubehead so as not to
expose yourself or anyone else to
radiation when making this test.
The voltage between X1 and X2 ranges
from approximately 60 to 120 volts. The
actual voltage will be based on the
position of the kilovoltage selector knob.
The voltage reading can only be
obtained when the exposure switch or
foot switch is depressed. Cover tube port
opening with lead in the event the
machine is working and x-rays are being
produced.
"LITTLE G I A N T 3 0 "
a small unit doing a BIG J O B
Universal X-Ray
Division of Chemetron Corporation
4 0 1 4 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
section f o u r
MAINTENANCE
3. Disconnect terminal M1 and connect
D.C. Milliameter (reverse lead if meter
reads b a c k w a r d ) between this te r m in a l
and the binding post f r o m w h i c h it w a s
removed. If on making an e x p o s u r e t h r u
the t i m e r this meter reads, then there is
a short between M1 and Ground in the
control or head to control c a b l e — o r the
mA. meter on the control is shorted and
needs replacement.
4. Determine if x-rays are being p r o d u c e d
by means of a f l u o r o s c o p i c screen or by
directing rays onto an open cassette in a
darkened room to see if intensifying
screen will g l o w w h e n x-rays are t u r n e d
on. Exercise care by limiting size and
direction of beam so as not to strike any
personal with direct radiation. If x-rays
are p r o d u c e d and milliameter still d o e s
not r e a d — t h e n the possible t r o u b l e is a
short between M1 and G r o u n d in the
x-ray head.
5. If all of the above points c h e c k t h r u
satisfactorily, then the t r o u b l e is in the
x-ray head and is p r o b a b l y an open
circuit. This can only be established by
examining the inside of the x-ray h e a d .
SERVICING THE T U B E H E A D
Universal t u b e h e a d s are assembled by a
careful and t h o r o u g h p r o c e s s w h i c h finally
includes v a c u u m degassing of the t u b e h e a d
and the insulating oil and filling the t u b e h e a d
with oil under v a c u u m . This t h o r o u g h
assembly process largely a c c o u n t s f o r the
success and long o p e r a t i n g life of Universal
t u b e h e a d s . At the same time, the need f o r
this processing d u r i n g assembly makes it
impractical for any but the most c o m p l e t e l y
e q u i p p e d service stations to p e r f o r m
repairs on Universal t u b e h e a d s . If a
ehead is low in oil but otherwise
sfactory, oil can be a d d e d by f o l l o w i n g
the p r o c e d u r e in subsequent paragraphs.
M I L L I A M M E T E R INDICATES BUT
FLUCTUATES
Check for l o w o i l c o n d i t i o n .
The 30 mA. controls covered by this
instruction manual have an adjustable
x-filament limiting resistor mounted b e h i n d
the meters and easily accessible for
adjustment. This is a 50 watt, 125 o h m .
cylindrical resistor, and adjustment is
achieved by loosening the band locking
screws and repositioning the b a n d .
Retighten the band locking screw after
adjusting.
The bag should be only about 1/3 full
(with no air) when head is at room
temperature. Unless p r o p e r facilities are
available this should be done at the
factory.
2. This may be caused by a defective x-ray
tube, either gassy or punctured or
broken.
2. Loose connections within the unit or
within the supply, or at the line c o r d
plug may cause milliampere fluctuations.
Loose connections of the filament circuit
controlling the milliampere output can be
c h e c k e d by examining the termination of
F1 and F2 at the tubehead and flexing the
c o r d where it enters the x-ray head to
detect possible intermittent breaks in
the wire.
3. Severe fluctuations of the milliameter
may indicate a gassy x-ray tube. If all
other points have been c h e c k e d , it can
be assumed that the t r o u b l e is in the
x-ray head and may be a gassy or
broken tube. If just received retain
shipping cartons and request
inspection by carrier so as to file claim
for c o n c e a l e d damages.
4. Severe fluctuations of the milliamperes
may also indicate an a r c i n g in the
x - r a y h e a d caused by an air pocket, or a
possible short. See item 1 above (low oil).
SERVICING THE C O L L I M A T O R
The light bulb in the c o l l i m a t o r has a
limited life, and will have to be replaced
relatively frequently. Refer to instructions
s h i p p e d with the c o l l i m a t o r for the
specifications of replacement light bulbs,
and for detailed instructions on how to
replace the bulb.
1. Tip t u b e h e a d so the terminals (low
voltage leads) are at highest point. This
will c h e c k out f o r arcing or mA
fluctuations c a u s e d by a low in oil
c o n d i t i o n . In this position the oil will
cover all the high voltage c o m p o n e n t s
QUICK CHECK DATA
Line c u r r e n t is d i r e c t l y p r o p o r t i o n a l to the
p r o d u c t of kVp. a n d m A . and operation at a
lesser p r o d u c t of k V p . and mA. will result in
a p r o p o r t i o n a l l y " r e d u c e d line c u r r e n t .
c l i p on a m m e t e r placed around one of the
t w o line wires. T h e readinqs shown are f o r
230 volt lines. On 115 volt lines d o u b l e the
value s h o w n in c h a r t .
Reading line current draw of the control c a n
q u i c k l y establish if the x-ray control and
t u b e h e a d are f u n c t i o n i n g properly. Use a
For precise evaluation of t u b e h e a d only see
p a g e 5. Chart on page 5 provides normal
current values measured in the X1 lead
(primary of H.T.) of the t u b e h e a d .
LINE CURRENT FOR 230 V O L T LINE
(Approx.)
X-Fil
Preread
Set kV C o n t r o l To
Q
5 mA.
15 m A .
30 m A .
1.2 a m p s .
3.5 a m p s .
6.7 a m p s .
X-FIL LIMITING R E S I S T O R - 3 0 mA.
CONTROLS ONLY
and any air pocket will be confined to
this low voltage position of the tubehead
w h i c h can operate w i t h o u t submersion.
If tu b ehe ad operates satisfactorily in this
position then c h e c k oil level by removing
cover and oil filling p l u g — b e i n g careful
that head is t i p p e d up so that oil filling
nole is at highest level. When removing
oil filling plug, finger should be held over
expansion bag oil filling hole so that
when v a c u u m is broken, that oil will not
fill expansion bag compl etel y. Keep bag
oil filling hole below level of oil filling
plug or air will get into expansion bag.
V
1.6 amps.
4.7 amps.
9.5 amps.
page nine
63
72
80
CIRCUIT BREAKER OPENS REPEATEDLY
1. Check item 1 above (Low oil).
3. It may also be caused by a high voltage
short in the x-ray head other than the
x-ray units.
4. If the x-ray head were to lose an
excessive amount of oil as a result of
an oil leak, it w o u l d arc over, causing
the circuit breaker to kick out.
5. The above conditions will be e v i d e n c e d
by a tendency for the pointer on the
milliameter to fly across the scale and go
back t o " O " a s the circuit b r e a k e r opens.
6. It may indicate a short in the control or
within the cable between the control and
s h o c k p r o o f head. To eliminate the s o u r c e
of trouble being in the head, d i s c o n n e c t
X1 and X2 from the head. Tape the e n d s
of the terminals and try to operate the
unit again. If the circuit breaker does not
kick out, then the trouble is in the x-ray
head.
C H E C K I N G TIMER
Periodically c h e c k the timer for a c c u r a c y
and also to be assured that the timer knob
or pointer set screw has not loosened a n d
is indicating the wrong time setting.
HOW TO A D J U S T THE TIMER
The timers used with these units contain
means to compensate for contactor lag, and
the adjustment is quite simple. Set the
timer dial to 1/15 second and adjust t i m e r to
obtain 4 dots with a spinning top. (See
F i g . 2) This adjustment will not affect the
longtime calibration by any significant
amount.
" L I T T L E GIANT 3 0 "
a small unit doing a BIG J O B
Universal X-Ray
section four
Division of Chemetron Corporation
4 0 1 4 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
s e c t i o n five
MAINTENANCE
FUSE L O C A T I O N S
Cat. 3335 controls contain five fuses. Three
fuses clip into a triple f u s e b l o c k mounted
on the chassis. Use 3 a m p or 8 amp 250 volt
3AG fuses for replacement as indicated on
the chassis beside the fuseblock.
The remaining two fuses mount into
fuseclips located on the rear of the Universal
solid state timer circuit board and readily
accessible from the rear. Use 8 / 1 0 amp.
250 volt 3AG fuses for replacement.
C O L L I M A T O R 24 V O L T POWER SOURCE
Terminals C1 and C2 in the control provide
24 volt (190 watt) ac source necessary to
_ perate the light beam lamp in the
collimator.
MISCELLANEOUS
C H E C K I N G TIMER
Periodically c h e c k the timer for a c c u r a c y
and also to be assured that the t i m e r knob
or pointer set screw has not loosened and
is indicating the w r o n g time setting.
TIMER C A L I B R A T I O N
The timer calibration can be c h e c k e d by any
of the well known methods. Perhaps the
simplest is to use a spinning t o p f o r short
times and a cycle c o u n t e r f o r long times.
Check the timer at 1 / 2 0 , 1 / 2 , 1 and 5
seconds. If exposure time deviates f r o m
preset time by more than 1 cycle f o r 1 / 2 0
and / 2 second settings, or by more than
1 0 % for the 1 and 5 s e c o n d settings,,
recalibrate timer. To recalibrate t i m e r see
Fig. 2
under heading HOW TO A D J U S T
THE TIMER.
1
SHORT IN mA. METER CIRCUIT
. If mA. meter b o u n c e s around or does not
read although there seems to be current
flow t h r u the tube then c h e c k for a shorted
mA. meter, short in wiring to the mA. meter
or a short in the mA. to g r o u n d meter
protection gap located at the transformer
terminals.
KILOVOLTMETER C A L I B R A T I O N
This test requires a 150 volt ac voltmeter
having an a c c u r a c y of 1% or better, and of
known calibration. Connect the test voltmeter across the terminals of kilovoltmeter
in the c o n t r o l . T u r n on the machine and vary
the voltage by means of the kilovolt control
selector s w i t c h . The voltage readings on
the test meter should be c o m p a r e d with
the a.c. volts on the top red scale of the
control voltmeter.
M A X I M U M DEVIATION
Assuming that the x-ray e q u i p m e n t is
properly installed and maintained a c c o r d i n g
to the instructions s u p p l i e d , and a c c e p t e d
p r o c e d u r e s are f o l l o w e d .
The m a x i m u m deviations given here f o r
individual control settings are b r o a d and do
not reflect on the ability of the x-ray unit to
conform to the R e p r o d u c i b i l i t y requirements
listed under the Radiation Control A c t of
1968, 78.213-2b(1) Coefficient of v a r i a t i o n
defined as, " F o r any specific c o m b i n a t i o n
of selected t e c h n i q u e f a c t o r s , the estimated
coefficient of variation of radiation
exposures shall be no greater than 0.05.
KILOVOLTS
Kilovolts delivered to the x-ray t u b e will not
deviate f r o m the indicated value by more
than ± 2 0 % of the m a x i m u m kVp.
'LLIAMMETER C A L I B R A T I O N
This test requires a dc milliammeter having
a full scale reading approximately the same
as the control milliammeter, with an
a c c u r a c y o f 1 % o r better, and o f known
calibration. Connect the test milliammeter
directly in series with the control
milliammeter by removing the lead f r o m one
of the control milliammeter terminals and
connecting that lead to the test
milliammeter. Then connecting together the
empty terminals of the two milliammeters.
Read both meters at each of the
milliammeter selector values and record the
control milliammeter error. If the error
e x c e e d s 5% of full scale, replace the
milliammeter.
QUICK ACTION METER A V A I L A B L E
Universal has available a Cat. 3700 q u i c k
action (approx. Va second) zero overshoot,
test meter w h i c h can be purchased for
servicemen to use in the field ( p r i c e $50
net). This will assure obtaining a more
accurate reading with relatively short
exposures, short enough not to overload
the tube.
EXPOSURE TIME
Time of exposure will not deviate f r o m the
value preset on the t i m e r scale by more
than the f o l l o w i n g :
1/60 to 1/10 s e c o n d — 1 c y c l e
3 / 2 0 to 6 s e c o n d — 1 5 %
MILLIAMPERES
T h e milliamperes passing t h r u the
X-Ray tube will not deviate f r o m the
indicated value by more than 2 0 % of
full scale.
MISCELLANEOUS
NOTE: T h i s section contains special
a d d i t i o n s and c o r r e c t i o n s to assembly,
o p e r a t i o n and maintenance instructions and
s h o u l d be c o n s u l t e d before proceeding
with assembly.
This s e c t i o n five provides a means for
e x p a n d i n g the usefulness of this manual by
insertion of newly developed data gained
f r o m field e x p e r i e n c e and for recording
data d e v e l o p e d by the assembler or user
a p p l i c a b l e to local conditions.
C H E C K I N G INVERSE SUPPRESSOR IN 30
MA. C O N T R O L
When a t u b e h e a d fails in use the inverse
s u p p r e s s o r may be subjected to an unusually high c u r r e n t d r a w and thus short out.
T h e c o n t r o l w o u l d still function even with a
s h o r t e d d i o d e and w o u l d only manifest itself
by a h i g h e r than normal high tension
p r i m a r y c u r r e n t draw.
It is s u g g e s t e d that the 30 mA. control be
c h e c k e d w i t h the Cat. #3205 t u b e h e a d to
establish that the inverse suppressor d i o d e
is f u n c t i o n i n g and not shorted out.
Use a clip-on ammeter in the X1 c i r c u i t (the
t e r m i n a l s under the t u b e h e a d c o v e r are
m a r k e d ) . Set the control for 5mA. C h e c k the
c l i p on a m m e t e r readings at M, Q and V
setting of kilovoltage. Y o u should get a p p r o x i m a t e l y 3.5 to 4 a m p e r e s . It should be
a b o u t the same at all the kV. settings.
A h i g h e r reading, a p p r o x i m a t e l y double
w o u l d indicate a possibility of a shorted
d i o d e in the control c o n t a c t o r circuit (inverse
s u p p r e s s o r ) . See wiring d i a g r a m .
Replace the diode if s h o r t e d . The diode
values are 400 volts, 25 amperes.
In rare instances and because of i m p r o p e r
field c h a n g e s made on the control or t u b e head it is possible for the diode to be
in g o o d c o n d i t i o n and yet a higher than
normal c u r r e n t exists in the X1 lead. This
may be c a u s e d by i m p r o p e r phase relationship of the d i o d e and the x-ray t u b e h e a d .
It can also be caused by shorted turns in the
s e c o n d a r y or a high resistance short
s o m e w h e r e in the hi-volt circuit. Factory
repairs or replacement is necessary.
For p r e c i s e evaluation of t u b e h e a d o n l y see
p a g e 5. Chart on page 5 provides normal
c u r r e n t values measured in the X1 lead
(primary of H.T.) of the t u b e h e a d .
See SECTION FIVE f o r more " T r o u b l e
s h o o t i n g " information that may have been
a d d e d later to this m a n u a l .
p a g e ten
Universal X-Ray
" L I T T L E G I A N T 30"
a small x-ray unit d o i n g a BIG JOB
Division of Chemetron Corporation
4 0 1 4 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
s e c t i o n five
MISCELLANEOUS
CAUTION
DURING C O L D WEATHER SHIPMENT
OF X - R A Y HEADS
Exposure to c o l d weather during shipment
may cause oil in x-ray head to contract,
creating a condition of " l o w in o i l , " w h i c h
can cause arc over or tube puncture, and
d a m a g e to x-ray head. Slowly shaking head
b a c k a n d f o r t h and listening f o r a splashing
of oil will determine if head is low in o i l .
A splashing sound can also be caused by a
tube b r o k e n in shipment. This can readily
be d e t e r m i n e d by making an x-ray exposure
at the lowest setting of Pkv. Low oil will
cause arcing and resultant high current
draw.
Shipment and outside storage during
extreme c o l d w e a t h e r can cause insulating
oil in t u b e h e a d to contract beyond the
volume of oil retained in the expansion b a g .
REVISED PANEL LAYOUT INTRODUCED
APRIL, 1979
Carton may act as an insulator—therefore
remove f r o m c a r t o n and permit e x p o s e d
t u b e h e a d to w a r m up to room t e m p e r a t u r e .
This may require 24 hours or longer. C h e c k
o u t at low values of kilovolts and gradually
bring up to full value.
To mark preset volts and knob position
on chart for 15, 20, 25, and 30 mA.
settings respectively, one of two
methods can be used:
Be sure t u b e p o r t is covered w i t h
a d e q u a t e sheet lead or that c o l l i m a t o r
o p e n i n g i s c l o s e d and o r covered w i t h sheet
lead t o prevent e x p o s u r e t o radiation
during testing.
BASIS OF MEASUREMENTS OF KVP.,
AND TIME
MA.,
The basis upon which the maximum
deviation of kVp. is stated is a
sphere gap test, or a calibrated
high voltage bleeder unit such as
the Machlett Dynalyzer.
The measurement basis upon which
the maximum deviations of mA. are
stated is a D.C. milliameter calibrated against a laboratory
standard meter, in series with the
x-ray tube.
The measurement basis upon which
the maximum deviations of exposure
time is stated are half cycle
impulses of the 60 hertz power
line measured at the primary
winding imput to the high voltage
transformer or in the secondary
circuit by means of a high
voltage bleeder unit and an
oscilloscope.
page eleven
1.
Lay a strip of transparent tape
over the chart area (tape such
as scotch transparent), and indicate values with a pen. To prevent smudging, lay a second strip
of tape over the first, or;
2.
Using a permanent dry marker,
(such as Carter's "Marks A Lot")
write in the values on the chart.
These values can be removed with
alcohol without damaging the
paint on the control panel.
LINE
VOLTS
97
104
110
117
123
130
205
211
217
224
230
237
243
250
CONNECT
L1 to
1
1
1
1
1
1
0/S1
0/S1
0/S1
0/S1
0/S1
0/S1
0/S1
0/S1
CONNECT
L2 to
9
10
11
12
13
14
7
8
9
10
11
12
13
14
30 MA. "LITTLE GIANT
CONTROL
CAT. NO. 3335
SCHEMATIC - SEE 3335 CONTROL WIRING DIAGRAM FOR DETAILS
Universal X-Ray
Division of Chemetron Corporation
4014 West Grand Avenue
Chicago, Illinois 60651 U.S.A.
Telephone: (312) 276-4487
Cable UNIVAPROCO
#040976
CUT ALONG DOTTED LINE AND PUT UNDER PLASTIC ON FRONT OF #3335 CONTROL
USE THIS CHART TO OBTAIN THE ACTUAL VALUES OF KILOVOLTAGE UNDER LOAD AT A
PARTICULAR MILLIAMPERE (MA.) SETTING.
N
0
P
Q
R
S
T
U
V
W
X
No Load Primary (Ep)Volts 60
65
71
77
83
88
95
102
108
115
123
129
Load Pri. Volts 58
at
1 5 mA. kVp. (kilovolts) 40
63.5
69
75
81
87
93
99.5
106
112
118.5
124.5
44
50
55
60
64
69
74
80
85
92
Load Pri. Volts
20 mA. kVp. (kilovolts)
Load Pri. Volts
at
25 mA. kVp. (kilovolts)
Load Pri. Volts
at
30 mA. kVp. (kilovolts)
57
62.5
68.0
73.5
80
86
92
98
105
111
117
32
39
44
48,
53
59
64
71
76
80
85
62.5
68
73.5
79
85
91
98
104
28
34
38
44
50
54
59
65
71
76
56
62
67.5
73
78.5
84.5
90.5
96,5
103
109
24
30
35
40
45
50
55
60
65
72
KV KNOB SETTING
at
M
56.5
109.5
96
123
91
1.16
122
80
85
115.5
76
121.5
81
It is recommended that ONE value of mA. be selected and used and the time varied
for variations in density requirements (mAs.). A FIXED value of kilovoltage can
be selected to provide the desired contrast and exposure latitude.
The milliamperes (mA.) setting is preestablished by recording the PRESET VOLTS.
An approximation of mA. can be obtained by setting the mA. knob to a prerecorded
position. An accurate presetting of mA. is made by setting the mA. knob to the
recorded PRESET VOLT reading on the voltmeter. See manual for details.
Preset Volts
Knob Position
Preset Volts
15 mA.
25 mA.
20 mA.
30 mA.
Universal X-Ray
Division of Chemetron Corporation
4 0 1 4 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
Knob Position
FOR REVISED PANEL LAYOUT INTRODUCED APRIL, 1979 SEE PAGE 11.
Universal X-Ray
Division of Chemetron Corporation
4 0 1 4 West Grand Avenue
Chicago, Illinois 60651
Telephone: (312) 276-4487
MAINTENANCE S C H E D U L E FOR R A D I A T I O N
S A F E T Y OF X - R A Y APPARATUS
In order to assure continued compliance to the
Federal Performance Standards, maintenance inspections and tests should be carried out by
qualified personnel on original installation and
at intervals of 6 months or less. Specific
instructions for performing these maintenance
activities are provided by the individual manufacturers.
This schedule relates- to conformance to the
Federal Performance Standards and is not intended
to assure general equipment performance which must
be carried out independently.
TUBE ASSEMBLIES:
1.
2.
3.
Radiation Leakage.
Look for obvious physical damage which would
affect radiation shielding and proper beam
limiting device function.
Beam quality.
Confirm that the minimum filtration required is
in the useful beam. Check interlocks where
applicable.
Field limitation and alignment.
Check indicators of beam axis and centering.
9.
10.
FLUOROSCOPIC IMAGING ASSEMBLIES - NON IMAGE
INTENSIFIED:
1. Radiation leakage.
Look for obvious physical damage which would
affect radiation shielding.
2.
Primary protective barrier.
Check that the entire useful beam is intercepted
by the primary barrier at any S.I.D. and that
the fluoroscopic tube shall not produce x-rays
if the barrier is not in the intercepting
position. Check to be sure lead glass has not
been unknowingly replaced by ordinary plate glass.
3.
GENERATORS and CONTROLS:
1.
2.
Line voltage and voltage regulation.
Measure line voltage and voltage regulation to
confirm that both are within manufacturer's
specifications and that supply line is connected to the proper line terminals, if applicable.
Calibration.
a) Perform the manufacturer's calibration procedure, including, but not necessarily
limited to, testing and adjusting kV, mA,
mAs, and timer factors to specifications
in manufacturer's instructions.
b)
Confirm that exposure cannot be made if
timer is not set on a specific time or if
timer is set to "zero", if applicable.
3.
Contactors and relays.
Inspect electromechanical contactors and relays
for pitting, poor contact, loose, or missing
parts. Replace if necessary.
4.
High tension cable and transformer bushings.
Check for proper filament circuit contact to insure consistant mA. output.
5.
Collimator filter interlock.
Confirm, where applicable, that an exposure cannot be activated at 50 kV and above, if the
minimum required filtration is not in place.
Visual exposure indicator.
Confirm that the means provided and specified by
the manufacturer for indicating, visually, the
occurrence of an x-ray exposure (mA meter, pilot
light, etc.) is functioning during and only
during an exposure.
6.
7.
8.
Audible exposure indicator.
Confirm that the audible indicator provided by
the manufacturer to indicate the termination
of an x-ray exposure is functioning in the
manner specified by the manufacturer and only
in the manner specified.
Inspect and test dials and knobs.
Inspect knobs on timers, kilovoltage, millampere
selectors and any other adjusting knobs to be
sure that the pointer is indicating to the
proper value.
X-ray exposure switch.
Confirm that any switch provided for activating
an x-ray exposure requires continuous pressure
to maintain the exposure or that release of the
switch terminates the exposure.
Warnings and indicators legible.
Inspect and confirm that all warning labels and
embossed, painted, silk screened, or other
wearable technique factors indicators have not
been defaced or worn so as to be illegible.
Check that the means provided to further limit
field size function properly, and that a
minimum field size of 5 x 5 cm. at maximum S.I.D.
can be provided.
4.
Fluoroscopic exposure rate.
Measure fluoroscopic radiation dose rate and
adjust, if necessary, to not more than 5 R/
minute or not more than 10 R/minute, depending
on equipment. Check B.R.H. requirements.
TABLES:
1. Aluminum equivalent.
Inspect table tops and cradles for any physical
damage, alterations or deviations from the
certified model which might alter the attenuation
characteristics.
CRADLES:
1. Beam attenuation.
Check that the cradle has not been modified or
changed ,
that the aluminum equivalence exceeds
2.0 mm.
CASSETTE HOLDERS:
1.
Inspect the front cover, if provided, of the
cassette holder for any physical damage or
modifications which would alter the attenuation
characteristics.
2.
Interlocks.
Test and confirm the proper operation of interlocks, if provided for the operation of positive
beam limitation.
Alignment indicators.
Test and confirm the proper operation and accurate
indications of means provided to accomplish alignment between the x-ray field and the image
receptor.
Alignment in Positive Beam Limitation (P.B.L.).
If provided for operation with positive beam
limitation, test and confirm proper°alignment
between the x-ray field and the image receptor.
3.
4.
(continued
from
preceding
page)
MAINTENANCE S C H E D U L E FOR R A D I A T I O N
S A F E T Y O F X - R A Y APPARATUS
BEAM LIMITING DEVICES:
1. Leakage Radiation.
Inspect beam limiting device and its attachment
to the x-ray tube housing for physical damage,
loosening or wear which might affect leakage
radiation. Verify that the combination of tube
housing and beam limiting device is listed as
compatible.
2.
3.
4.
Beam quality.
a) Verify that all filtration elements, incidental and added, as provided by the certified
beam limiting device and tube housing, are
present and show no evidence of physical
damage or alteration which might alter attenuation.
b)
Verify operation of filter - kV interlock in
systems with more than one thickness of
filtration.
c)
Perform such maintenance as specified by
manufacturer, e.g., tightening of hardware,
lubrication, etc.
Variable field.
Verify functioning of stepless adjustment of x-ray
field size. Verify that minimum field size of
5 x 5 cm. can be achieved at 100 cm,
Visual definition.
a) Verify that misalignment between the visually
defined field and the x-ray field does not
exceed 2% of S.I.D.
b) Verify average illumination exceeds 160 lux
(15 foot candles).
c)
5.
6.
• 7.
8.
Intraoral image receptors.
a) Verify presence and integrity of source to
skin distance limiting devices specified
for the certified component.
b) Verify maximum field size at minimum SSD
is 7 cm. or 6 cm., respectively, if minimum
SSD is greater than or less than 18 cm.
Single image receptor size.
Verify presence, integrity and functioning of
means provided to limit x-ray filed size to
not greater than the image receptor, and to
align the field and receptor centers to within
2% of S.I.D.
9.
Other x-ray systems.
Verify presence, integrity and functioning of
means specified and provided for the certified
component to limit the x-ray field such that
each dimension does not exceed image receptor
size by more than 2% of S.I.D. and to align
the centers of the x-ray field and receptor to
within 2% of S.I. Verify presence and visibility of, markings identifying image receptor
size and S.I.D.
10.
Field limitation and alignment.
a) Verify that the total misalignment of
x-ray field with the respective edges of
the selected portion of the image receptor
does not exceed 3% of S.I.D. for length
or width, nor 4% of magnitudes for the two
directions.
b)
Verify that edge contrast ratio of light field
exceeds 4 and 3 respectively for stationary
and mobile radiographic equipment.
d) Perform manufacturers routine maintenance.
Field indication and alignment.
a ) " Verify the proper functioning of the means for
alignment of the center of the x-ray field
with the center of the image receptor.
b) Verify that the numerical indications of field
size result in x-ray field dimensions in the
plane of the image receptor are within 2% of
S.I.D. of the dimensions of the•image receptor.
c) Perform manufacturers routine maintenance.
Positive beam limitation.
a) Verify automatic adjustment of x-ray field size
to image receptor size within 5 seconds of
insertion of image receptor, or inhibition of
exposure until field congruency is obtained,
b) Verify that the x-ray size conforms to that of
the image receptor within 3% of S.I.D. per axis
and 4% of S.I.D. total.
c) Varify operation of optional field size reduction and that field can be reduced to 5 x 5 cm.
or less at 100 cm.
d) Verify that return to positive beam limitation
occurs upon a change in image receptor.
e)
Verify that the bypass mode, where provided,
functions when not using the cassette tray or
permanently mounted vertical cassette holder,
and when either beam axis or table angulation
if not within 10° of the horizontal or
vertical during any part of the exposure.
Verify automatic return to positive beam
limitation when more of the above are.
applicable.
f)
Verify operation of override key, where
provided.
c)
d)
11.
Verify that x-ray field size can be adjusted smaller than the selected portion
of the film, and that at maximum S.I.D.
a field size of less than 5 x 5 cm. can be
provided.
Verify that the centers of the x-ray and
selected film portion coincide within 2%
of S.I.D.
Perform manufacturers routine maintenance.
Source skin distance (mobile units).
Verify the presence and integrity of the means
specified and provided for the certified component to limit source skin distance to no
less than 30 cm.
Check that the certification label and component
identification label are affixed to all certified
components.
Consult DHEW Publication No. (FDA) 75-8003 dated
July, 1974 for specific compliance requirements.
Also consult B.R-.H. Routine Compliance Testing
for Diagnostic X-Ray Systems or Components of
Diagnostic X-Ray Systems, to which 21 CFR Subchapter J is applicable, DHEW Publication (FDA)
75-8012 dated September, 1974 for details on test
procedures and equipment specifications,and details.
After initial installation, performance of these
periodic activities is the responsibility of the
owner/user, as they are not provided at no cost
under the manufacturer's warranty.