-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
MHDS
Operating manual
Modular differential pressure transmitter
MHDS
Overview documents
- Technical documentation MHDS
- Operating manual MHDS-M (this document)
MHDS-M-1
-2-
MHDS
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
Inhalt:
Safety instructions
page 3 - icons
Mounting
page 3
page 4
page 5
page 6
page 7
- mounting, putting into operation
- incoming acceptance
- storage
- identification
- scope of delivery
- notes for installation
- mounting flow measurement
- mounting flow measurement
- mounting level measurement
- mounting level measurement
- mounting differential pressure mesurement
- mounting differential pressure mesurement
- wall- and tube mounting
- turning enclosure
- check of the mounting
Electrical connection
page 8 - connection of the device
- test signal 4...20 mA
page 9 - output (working resistance)
- sceening and equipotential bonding
- check electrical connection
Operation
page 9
page 10
page 11
page 12
- on-site display
- operating elements
- on-site operation (operating elements outside)
- on-site operation (operating elements inside)
- on-site operation (operating elements inside)
Putting into operation
page 13 - position adjustment
- flow measurement
page 14 - level measurement
page 15 - level measurement
page 16 - differential pressure measurement
Input
page 17
Dimensions
page 17
Process connection
page 17
Electronics
page 18
HART communication
page 18
Technical data
page19
MHDS-M-2
HART
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
MHDS
Safety instructions
Used icons
!
Warning!
A non-observance can cause injuries to persons or lead to demolition of the device.
!
Attention!
A non-observance can cause a faulty operation of the device.
i
Information!
A non-observance can have influence on the operation of the device or cause unintentional reactions of
the device.
Mounting, putting into operation
!
Ther MHDS is a differential pressure transmitter for flow, level and differential pressure measuring. The
manufacterer of the device is not liable for defects, which are resulted from incorrect use or use other than
that designated.
The pressure transmitter meets the state of the art with taking into account the relevant regulations and EC
standards. When the use is not appropriate or in accordance with the requirement, from the device can start
application-related dangers, eg an escape of fluid when mounted or adjusted wrong.
A non-observance of the valid safety regulations for this case of application may cause serious injuries
and/or damages. Only personnel with the needed qualification, who is authorised by the operator, is
allowed to carry out mounting, electrical connection, putting into operation, operation and maintenance of
the pressure transmitter.
The specialist staff must have read and understood this operating manual. Instructions , which are included in this manual, have to be followed.
Modifications and repairs to the device are permissible only when they are allowed expressly in this
documentation.
Mounting
Before mounting:
Acceptance
- When receiving the goods check the packaging and the contents for damage
- Check the goods for completeness (eg compare delivery note with order data)
Storage
- The device has to be stored in a dry, clean area and protected against damage from impact
- Storage temperature: -40...+85 °C
Identification
- The type plate shows the maximum working pressure (Pmax = MWP = maximum working pressure). This value
refers to a reference temperature of 20 °C.
- The allowed pressure values at higher temperatures can be found in the relevant standards.
- The test pressure of the device is corresponding with the overload pressure (see table on page 17).
- The used abbreviation PS in the Pressure Equipment Directive (97/23/EG) corresponds to the MWP (Maximum
working pressure = Pmax) of this device.
Details on the type plates (these details can vary)
Type: name of the device = MHDS
TAG-No: indentification number within the installation
Date: date of completion
Pmax: = MWP = maximum working pressure)
Input: kind of pressure (differential pressure)
Supply: voltage supply = 15...45 VDC
Output: output signal = 4...20 mA HART
Range: measuring range (adjusted)
Order number / item number: 200-xxxxx (x = variable)
SN: serial number
Degree of protection: IP65
MHDS-M-3
MHDS
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
Mounting (continued)
Scope of delivery
The delivery includes:
- differential pressure transmitter MHDS
- mount for wall- and tube mounting
- accessories (option)
Supplied documents:
- this operating manual MHDS-M
- option: final inspection and test report
- option: factory calibration form
- option: operating manual for programming software
Mounting
- Assembly dimensions see page 17
Notes for installation
- Due to the fitting position of the MHDS there may be a zero offset. Example: Although the storage basin is empty the
measured value not 0 (zero). It is possible to correct this zero point shift directly on the device by using the keys for
configuration or extenally by means of software for configuration. See page 10...12 in this manual or in the manual
for the software.
- When using a 3-valve or 5-valve manifold, the mounting, putting into operation and maintenance can be done
without interrupting the process.
- When laying the differential pressure pipes outside, take care of an adequate antifreezing protection, eg with a
parallel pipe heating.
- You can take from relevant standards (national or international) recommendations about laying of differential
pressure pipes (eg DIN 19210).
- Tubes for pressure drop have to be layed with a constant gradient of at least 10%.
- The enclosure of the electronics can be turned up to 360°. In this way the display of the electronic insert is readable
very well. See on page 7, too.
- A mount for wall- and tube mounting is included in the delivery.
Mounting for flow measurement
Flow measurement in liquids
A:
pitot tube / orifice plate
B:
stop valve
C:
3-valve manifold
D:
MHDS
E:
separator
F:
drain valve
Mount the pressure sensor MHDS below the measuring point. In this
way the differential pressure pipes are always filled with liquid and
possible gas bubble can rise back into the process piping.
A
B
B
+
D
E
E
F
F
Separators and drain valves are usefull if the medium contains solid
parts. Through this the deposit can be removed.
C
Flow measurement in gases
A:
B:
C:
D:
pitot tube / orifice plate
stop valve
3-valve manifold
MHDS
Mount the pressure sensor MHDS above the measuring point. Possible
existing condensate can run off into the process piping.
D
C
B
+
MHDS-M-4
-
B
A
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PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
MHDS
Mounting (continued)
A:
B:
C:
D:
E:
F:
G:
A
G
Flow measuring in steam
pitot tube / orifice plate
stop valve
3-valve manifold
MHDS
separator
drain valve
condensate trap
G
B
B
+
D
Mount the pressure sensor MHDS below the measuring point.
Mount the condensate trap at the same level as the tapping point and
the same distance to the MHDS.
Fill the differential pressure pipes before putting into operation to the
height of condensate traps.
E
E
F
F
C
Mounting for level measurement
Level measurement in an open vessel
A:
B:
C:
D:
E:
F:
minus is open to atmosphere
stop valve
vessel
MHDS
separator
drain valve
Patm
C
+
min
A
E
Mount the pressure sensor MHDS below the measuring
point. In this way the differential pressure pipes are always
filled with liquid.
Minus is open towards atmosphere
D
F
B
Level measurement in a closed vessel
A:
B:
C:
D:
E:
F:
vessel
stop valve
3-valve manifold
MHDS
separator
drain valve
B
max
A
B
min
Mount the pressure sensor MHDS below the measuring
point. In this way the differential pressure pipes are always
filled with liquid.
Minus has to be connected above the maximum level.
Separators and drain valves are usefull if the medium
contains solid parts. Through this the deposit can be
removed.
+
D
E
E
F
F
C
MHDS-M-5
MHDS
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PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
Mounting (continued)
Level measurement in a closed vessel with
superimposed steam
A:
B:
C:
D:
E:
F:
G:
vessel
stop valve
3-valve manifold
MHDS
separator
drain valve
condensate trap
G
max
B
A
B
min
Mount the pressure sensor MHDS below the measuring
point. In this way the differential pressure pipes are always
filled with liquid.
Minus has to be connected above the maximum level.
Separators and drain valves are usefull if the medium
contains solid parts. Through this the deposit can be
removed.
The condensate trap ensures a constant pressure on minus.
+
D
E
E
F
F
C
Mounting for differential pressure measurement
Differential pressure measurement in fluids
A:
B:
C:
D:
E:
F:
filter (example)
stop valve
3-valve manifold
MHDS
separator
drain valve
Mount the pressure sensor MHDS below the measuring point. In this
way the differential pressure pipes are always filled with liquid and
possible gas bubble can rise back into the process piping.
Separators and drain valves are usefull if the medium contains solid
parts. Through this the deposit can be removed.
A
B
B
+
D
E
E
F
F
C
MHDS-M-6
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PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
MHDS
Mounting for differential pressure measurement (continued)
Differential pressure measurement in steam and gas
A:
B:
C:
D:
filter (example)
stop valve
3-valve manifold
MHDS
D
Mount the pressure sensor MHDS above the measuring point. Possible
existing condensate can run off into the process piping.
C
-
+
B
B
A
Wall- and tube mounting
37
Holder made of steel (zinc coated) for mounting the device on walls or tubes
is supplied with the device.
109
Supplied parts: holder, fixing clamp with nuts and washers.
The holder made of stainless steel can be selected as an option (additional
price).
When using a valve block, take it’s dimensions into account.
i
When mounting, please note:
- To avoid a scuffing, lubricate the fastening screws with multi-purpose
grease before mounting.
- In case of tube mounting: fasten the screw nuts of the fastening bow
with a torque of at least 30 Nm.
70 8
10
i
70 9
9
Dimensions in mm
Turning of enclosure
After unscrewing the M6 Allen screw the enclosure can be rotated up to 360°.
- release the screw with a 3 mm hexagon key
- turn enclosure (up to 360°)
- drive in screw again
maximum 360°
FIELD
TERMINALS
FIELD
TERMINALS
316
316
316
316
Check the mounting
After mounting of the transmitter carry out the following check:
- Check if all screws are screwed down tight
- Check if the screwed covers are screwed up
- Check if screw plugs / ventilating valves are screwed down tight
MHDS-M-7
-2-
MHDS
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
Electrical connection
- the supply voltage has to match the power supply which is given on the type plate. See also on page 3: identification
- before connecting the device, switch off the power supply.
- screw off the screwed cover of the terminal compartment.
- insert the cable via screwed cable gland (specification see below).
- carry out the connection according the illustration below.
- screw up screwed cover.
- switch on power supply.
A
Z
supply
S
B
C
D
4...20 mA
mA
1+
2-
test
signal
3+
E
FIELD
TERMINALS
Electrical connection 4...20 mA HART
A: Enclosure
B: Voltage supply 15...45 VDC (terminal 1(+) / terminal 2 (-))
C: 4...20 mA test signal between 2- and test point 3+
D: Internal earthing
E: External earthing
1+
2-
3+
Test
4...20
mA
The device has a protective system against overvoltage peaks, RF interferences and wrong polarity.
Voltage supply: between 15 ....45 VDC
Cable entry: screwed cable gland M20x1,5 (metal)
Cabel:
outer diameter: 6...12 mm
cross-sectional area: 0,5...1,5 mm²
shielded and twisted 2-wire cable (recommended)
Residual ripple: no influence on mA-signal up to 5% within nominal voltage range
Tapping the 4...20 mA test signal
test signal
The 4...20 mA test can be measured without interruption of
the low-potential circuit between terminal 3(+) and terminal
2(-). The output current is measured with an ammeter for
mA across a diode in the output circuit.
3+
The internal resistance of the ammeter should be less than
0,7 ohms to keep the error of measurement below 0,1%.
21+
MHDS-M-8
+
mA
4...20 mA
current loop
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PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
MHDS
Output (working resistance)
Load:
RLmax = (U - 15 V) / 0,0228 A
RL(max)
[ohms]
1333
1111
Voltage supply: 15...45 VDC
RLmax: maximum load resistance
U: Voltage supply
Please note: When using communication via a HART modem,
a comunication resistance of minimum 250 ohms has to be
taken into account.
i
666
222
15 20
30
Resolution:
Read cycle time:
Damping:
40 45 U[V]
current output: 16 bit
indication: adjustable (factory setting: 0...100%)
HART commands all 200 ms.
continuously adjustable from 0 to 160 µA via electronic insert inside the device, hand-held
equipment or PC-software. Factory configuration: 0 µA
Sceening and equipotential bonding
An optimal sceening against disturbances is to achieve if the sceening is connected on both sides ( on the device and
in the cabinet). If there are potential equalisation currents possible in the plant, only earth sceening on one side,
preferably the transmitter side. Installation of potential matching is not necessary.
Check electrical connection
After completition of the electrical installation carry out the following check:
- Check if the power supply matches the details of the type plates.
- Check if the device is connected as shown on page 8.
- Check if all screws are screwed down tight.
- Check if the screwed covers are screwed up.
When switching on the power supply the backlighting of the display in the electronic insert illuminates.
Operation
On-site display
The on-site display is a 3-line display (LCD). Indicated are measured values and dialog
texts.
Functions: 5-digit measured value display (including sign and decimal point), indication of
unit and a bargraph for indication of current.
Operating elements
Span
S
P
Zero
Z
F1
Below the type plate there are 2 key button for
easy configuration of zero, span, zero offset
compensation and reset of the device.
The layout of the 2 keys is marked on the
enclosure with “S” and “Z”
F2
The electronic insert with the display has 3
keys (P, F1, F2) for the configuration of the
transmitter. The keys are approachable
after screwing off the screwed cover.
MHDS-M-9
MHDS
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
On-site operation (external keys)
Below the type plate there are 2 key keys for easy configuration. Configurable are:
- Zero (lower range value)
- Span (upper range value)
- Zero offset compensation
- Reset of the device
Open the lock
Press the keys S and Z for 5 seconds simultaneously. The LCD sceen is
showing OPEN when the lock is opened.
Input pressure for 4 mA (zero) output
Set the input pressure to zero reference level. Press key Z for 2 seconds
and the output of the transmitter is 4,000 mA. The LCD sceen is showing
LSET.
Input pressure for 20 mA (span) output
Set the input pressure to span reference level. Press key S for 2 seconds
and the output of the transmitter is 20,000 mA. The LCD sceen is showing
HSET.
Zero offset compensation (compensation of position)
Set the input pressure level to zero (pressure value = 0 = atmosphere).
Press keys S and Z for 2 seconds simultaneously and the output of the
transmitter is 4,000 mA. The LCD sceen is showing PV=0.
Note: If pressure value / pressure range is >0,5, the zero offset
compensationis not possible. The LCD sceen is showing PVER.
Reset
Switch off the power of the device. Press keys Z and switch on the power
supply again. Go on to press key Z for another 5 seconds. The LCD sceen
is showing OK when the transmitter is reset.
Note: If pressure value / pressure range is >0,5, the zero offset
compensationis not possible. The LCD screen is showing PVER.
MHDS-M-10
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
On-site operation (internal keys)
The display is rotatable for approx. 330°
The electronic insert has 3 keys for configuration.
Configurable are:
- lower range value
- Zero offset compensation (compensation of position)
- Reranging starting measuring value
- Damping
- Fixed current output
MHDS
- upper range value
- Reset
- Reranging final measuring value
- Unit (mA, mbar, %)
Open the lock
Press the keys F1 and F2 for 5 seconds simultaneously. The LCD sceen is
showing OPEN when the lock is opened.
Input pressure for 4 mA (zero) output
Set the input pressure to zero reference level. Press key F2 for 2 seconds
and the output of the transmitter is 4,000 mA. The LCD sceen is showing
LSET.
Input pressure for 20 mA (span) output
Set the input pressure to span reference level. Press key F1 for 2 seconds
and the output of the transmitter is 20,000 mA. The LCD sceen is showing
HSET.
Zero offset compensation (compensation of position)
Set the input pressure level to zero (pressure value = 0 = atmosphere).
Press keys F1 and F2 for 2 seconds simultaneously and the output of the
transmitter is 4,000 mA. The LCD sceen is showing PV=0.
Note: If pressure value / pressure range is >0,5, the zero offset
compensationis not possible. The LCD sceen is showing PVER.
Reset
Switch off the power of the device. Press keys F2 and switch on the power
supply again. Go on to press key F2 for another 5 seconds. The LCD
sceen is showing OK when the transmitter is reset.
Note: If pressure value / pressure range is >0,5, the zero offset
compensationis not possible. The LCD screen is showing PVER.
MHDS-M-11
MHDS
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
On-site operation (internal keys) continued
Function of the keys: P: select function / store adjusted value
F1: change digit or decimal point / select characteristic
F2: select digit to be changed or decimal point / confirm selected characteristic
key P
adjustment
lower range
value
key P
Select with F2 the digit to be
changed or decimal point
Change with F1 the digit or
decimal point.
key P
adjustment
upper range
value
key P
Select with F2 the digit to be
changed or decimal point
Change with F1 the digit or
decimal point.
key P
adjustment
damping
key P
Select with F2 the digit to be
changed or decimal point
Change with F1 the digit or
decimal point.
key P
adjustment
display
mode
Select with F1 the needed
display mode.
key P
fixed
output current
key P
MHDS-M-12
Select with F1 the desired
current. Confirm the selected
current with F2
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
MHDS
Putting into operation
Check before putting into operation the mounting and the connection (see also page 7 and 9).
Compensation of position (zero offset compensation)
Because of the fitting position it is possible that there is a shift of the measured value. When the differential
pressure pipes are not connected, the indicated measured value is not 0 or indication is not 0 with an empty
vessel.
Flow measurement
Valves
1
Close valve 1
2
Fill the system with medium
Open valves 2, 3, 6, 7
3
4
5
6
Meaning
Installation (prefered)
4
medium flows in
+
If 5 valves are available, clean the differential pressure pipes if
necessary.
- gases: blow out with compressed air
- liquids: by rinsing
Close valves 2 and 3
the device is blocked
Open valves 8 and 9
blow out / rinse the differential
pressure pipes
Close valves 8 and 9
close valves after cleaning
2
5
-
Y
1
3
X
7
6
+
-
Deaerate the system
Close valves 2 and 3
lead medium into
Close valve 3
close negative side
Open valve 1
balance of positive and negative
side
Open valves 4 and 5 and
close them again after a
short time
system is filled with medium and
air escapes
Compensation of position: Carry out only if the process cannot be
blocked and the tie-in points (valves 6 and 7) are at the same
geodetic height.
Compensation see on pages 10...12.
In the other case the compensation of position has to be done in
step 7.
Set the system into operation
Close valve 1
disconnect positive from
negative side
Open valve 3
connect negative side
Now:
closed valves: 1, 4, 5, 8, 9
open valves: 2, 3, 6, 7
7
Compensation of position: carry out only if the process can be
blocked. In this case step 5 has not to be carried out.
(see pages 10...12)
8
Carry out adjustment (see pages 10...12)
6
7
+
4
Z
+
8
5
Y
Z
-
9
1
2
X
3
Above: installation for gases
Below: Installation for fluids
X:
Y:
Z:
3-valve manifold
MHDS
Separator
1:
2; 3:
4, 5:
6, 7:
8, 9:
Equalising valve
Inlet valves
Vent valves
Stop valves
Drain valves
MHDS-M-13
-2-
MHDS
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
Putting into operation (continued)
Level measurement (open vessel)
Valves
Meaning
1
Fill vessel to a level above the lower tap
2
Fill system with medium
Open valve 6
3
medium flows in
system is filled with medium and
air escapes
4
Z
8
Set the system into operation
Now:
7
+
Deaerate system
Open valves 4 and 5 and
close them again after a
short time
4
Installation (prefered)
+
Closed valves: 4, 8
Open valve: 6
-
Y
6
Carry out adjustment (see pages 10...12)
Y:
Z:
4, 5:
6:
8:
5
MHDS
Separator
Vent valves
Stop valve
Drain valve
Level measurement (closed vessel)
Valves
Meaning
1
Fill vessel to a level above the lower tap
2
System mit Medium auffüllen
3
Installation (prefered)
6
Close valve 1
disconnect positive from
negative side
Open valves 6 and 7
Open stop valves
Vent positive side (if necessary, empty negative side)
Open valves 2 and 3
Open valves 4 and 5 and
close them again after a
short time
7
positive side is filled with fluid
+
4
positive side is filled with medium
and air escapes
Z
+
Set system into operation
Now:
5
MHDS-M-14
2
Closed valves: 1, 4, 5, 8, 9
Open valves: 2, 3, 6, 7
Carry out adjustment (see pages 10...12)
Y
Z
-
1
8
4
-
5
X:
Y:
Z:
3-valve manifold
MHDS
Separator
1:
2; 3:
4, 5:
6, 7:
8, 9:
Equalising valve
Inlet valves
Vent valvesl
Stop valves
Drain valves
X
9
3
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
MHDS
Putting into operation (continued)
Level measurement (closed vessel with superimposed steam)
Valves
Meaning
1
Fill vessel to a level above the lower tap
2
Fill the system with medium
Open valves 6 and 7
Installation (prefered)
6
open stop valves
Fill the negative differential pressure pipe to a level of the
condensate tap
3
4
Deaerate the system
medium flows in
Open valve 1
balance of posizive and negative
side
Open valves 4 and 5 and
close them again after a
short time
system is filled with medium and
air escapes
+
4
Z
+
Close valve 1
Disconnect positive from negative
side
Open valve 4
connect negative side
Closed valves: 1, 4, 5, 8, 9
open valves: 2, 3, 6, 7
Carry out adjustment (see pages 10...12)
-
5
Y
Z
-
1
8
Set system into operation
Now:
5
7
Open valves 2 and 3
2
X:
Y:
Z:
3-valve manifold
MHDS
Separator
1:
2; 3:
4, 5:
6, 7:
8, 9:
Equalising valve
Inlet valve
Vent valve
Stop valve
Drain valve
X
9
3
MHDS-M-15
-2-
MHDS
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
Putting into operation (continued)
Differential pressure measurement
Valves
1
Close valve 1
2
Fill the system with medium
Open valves 2, 3, 6, 7
3
4
5
6
Meaning
Installation (prefered)
4
medium flows in
+
If 5 valves are available, clean the differential pressure pipes if
necessary.
- gases: blow out with compressed air
- liquids: by rinsing
Close valves 2 and 3
the device is blocked
Open valves 8 and 9
blow out / rinse the differential
pressure pipes
Close valves 8 and 9
close valves after cleaning
2
5
Y
1
3
X
7
6
+
-
Deaerate the system
Close valves 2 and 3
lead medium into
Close valve 3
close negative side
Open valve 1
balance of positive and negative
side
Open valves 4 and 5 and
close them again after a
short time
system is filled with medium and
air escapes
Compensation of position: Carry out only if the process cannot be
blocked and the tie-in points (valves 6 and 7) are at the same
geodetic height.
Compensation see on pages 10...12.
In the other case the compensation of position has to be done in
step 7.
Set the system into operation
Close valve 1
disconnect positive from
negative side
Open valve 3
connect negative side
Now:
closed valves: 1, 4, 5, 8, 9
open valves: 2, 3, 6, 7
7
Compensation of position: carry out only if the process can be
blocked. In this case step 5 has not to be carried out.
(see pages 10...12)
8
Carry out adjustment (see pages 10...12)
MHDS-M-16
6
7
+
4
Z
+
8
5
Y
Z
-
9
1
2
X
3
Above: installation for gases
Below: Installation for fluids
X:
Y:
Z:
3-valve manifold
MHDS
Separator
1:
2; 3:
4, 5:
6, 7:
8, 9:
Equalising valve
Inlet valves
Vent valves
Stop valves
Drain valves
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
MHDS
Output
Measurand:
differential pressure
derived from this: flow rate (volumetric- and mass flow)
level (level, volume, mass)
Measuring ranges:
75 mbar up to 420 bar
nominal range
range limit
upper
(URL)
[mbar]
working range
smallest
adjustable
[mbar]
overload
[mbar]
range limit
lower
(LRL)
[mbar]
75
400
2000
7000
21000
70000
200000
420000
-75
-400
-2000
-7000
-21000
-70000
-200000
-420000
+75
+400
+2000
+7000
+21000
+70000
+200000
+420000
1,5
4
20
70
210
700
2000
4200
130
130
130
130
130
125% of range
125% of range
115% of range
[bar]
Dimensions
Dimensions in mm
~130
113
S
128
Z
F2
205
F1
120
P
316
H
L
316
view front
view side
view top
Process connection
M10
84 mm
Pressure connection:
1/4-18 NPT AISI 316L (1.4435)
Measuring membrane:
stainless steel 1.4435
Mounting:
M10
Supplied accessories:
2 ventilating valves AISI 316L (1.4435)
H
L
1/4-18 NPT
97 mm
MHDS-M-17
MHDS
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
Electronics
Electronics
- XS1 voltage supply 15...45 V
- XS2 connection sensor
- XS3 external keys
- XS7 display
- J1 solder bridge to select sensor supply
XS3
VS
Z
M
••
••
W
S
Z
II+
VL4
L3
L2
V+
••
••
••
••
••
XS1
XS7
••
L+
L-
T1
J1
v V+S+U-S-T
i
•••••
XS2
U3
HART Communication
HART tool:
The HART-Tool is a graphical user interface for the MH series with menu-driven progam for configuration. It
can be used for putting into operation, configuration, analysis of signals, data backup and documentation of the
device. Operating systems: Windows2000, Windows XP
Functions:
- Configuration of the devices in on-line operation
- Loading and storing the devices data (upload / download)
- Linearization of characteristic curve
- Documentation of the measuring point
Possible HART devices to use:
- HART interface (modem) with serial interface of a PC
- HART interface (modem) with USB interface of a PC
- Hand-held HART communicator
MHDS-M-18
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
MHDS
Technical data
Input
Differential pressure: 75 mbar / 400 mbar / 2 bar / 7 bar / 21 bar / 70 bar / 200 bar / 420 bar
Static pressure: 30...420 bar
Output
Analog: 4...20 mA, 2-wire, with superimposed communication signal (HART-protocol)
Signal range: 3,6...22,8 mA
Failure:
signal 3,6 mA
Accuracy
Type 75 mbar: 0,1% of FS up to turn down 5:1
±(0,1+0,01*URL/URV) for turn down 5:1 to 50:1
Types 400 mbar / 2 bar / 7 bar / 21 bar / 70 bar: 0,075% of FS up to turn down 10:1
±(0,0751+0,00751*URL/URV) for turn down 10:1 to 100:1
Types 200 bar / 420bar: 0,2% of FS up to turn down 10:1
±(0,2+0,01*URL/URV) for turn down 10:1 to 100:1
Influences:
static pressure: zero: ±0,1%/70 bar - range: ±0,2%/70 bar
supply: <0,005% of nominal range/1V
vibration: <0,01% of nominal range/g at 200 Hz
fitting position: zero drift, to compensate
span drift: without
temperature: <0,45%/55°C
Stability: ±0,1% of nominal range / 1 year
Settings
Rise-delay time: 5 s
Cycle time, update: 0,25 s
Damping: 200 ms (without concideration of electronic damping)
Filter adjustment: 0...160µA
Display
Visible range: 32,5x22,5 mm
Indication:
5-digits 7-segments, 8 mm height / 8-digits 14-segments, 5 mm height 7
bargraph with resolution 2%
Range:
-19999...99999
Supply
Voltage:
15...45 VDC (current loop)
Insulation resistance: >250 MOhm
Short circuit-proof: permanent
Reverse battery protection: yes (no destruction, no funtion)
Overvoltage protection: 500V
Environmental conditions
Operating temperature: -20...70°C
Ambient temperature: -20...70°C
Temperature medium: -40...104°C
Storing temperature:-40...+85°C
Humidity: 5...98% relative humidity
Mechanics
Material:
Enclosure ektronics: diecast aluminium
Measuring membrane: stainless steel 1.4435 / option:Hastelloy
Ventilating valve, joint pieces: stainless steel 1.4435
O-ring in contact with medium: Viton (FKM, FPM)
Flange screws: plain carbon steel, zinc coated
Type plate: stainless steel 1.4301
viewing glass: laminated glas
Process connection: 1/4-18 NPT
Dimensions:
see page 7
Protection:
degreeIP 65
Weight:
approx. 3,8 kg
Connection:
terminal screw (maximum 1,5 mm²), via srewed cable gland M20x1,5
Principle of measurement: capacitive
Standards:
IEC 61000-4-3 / Pressure equipment directive 97/23/EG
MHDS-M-19
MHDS
MHDS-M-20
-2-
PRESSURE
MODULAR DIFFERENTIAL PRESSURE TRANSMITTER
HART
Subject to change, version 41-050