1
4 System Specifications
This section contains information on the Portal systems and function.
4.1
Bx/FX/TDTx Module Overview
4.1.1
Layout
NOTE: The top Bx/FX/TDTx module is commonly called the “topshooter,” and that term is
used in this manual.
The Bx/FX/TDTx modules house the X-ray system and control electronics.
Figure 4-1 provides an overview of the Portal internal arrangement. Figure 4-1 shows a trucksize Z Portal, the internal arrangment of the automobile-size Z Portal and the Z Gantry are the
same.
American Science & Engineering, Inc.
Portal Inspection System FSM 291-9200-1 Rev. B
2
Bx/FX/TDTx Module Overview
Figure 4-1 Bx Portal Series Internal Arrangement (Typical)
The two side modules have identical arrangement, but they are oriented 1800 opposite to each
other. The internal arrangment of the top shooter differs from the side modules.
Figure 4-2 through Figure 4-4 show the internal arrangement of a side Bx/FX/TDTx module.
•
Figure 4-2 and Figure 4-3 show a view from the detector side, with the detectors and module
side structure removed.
•
Figure Figure 4-4 shows a view from the access side, with the side structure removed.
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Portal Inspection System FSM 291-9200-1 Rev. B
Bx/FX/TDTx Module Overview
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1
2
3
4
5
6
7
1
2
3
4
5
6
7
Electronics Panel
E-Stop Button
AC Power Supply (Typical, Module 1Only)
Main Circuit Breaker Box
Lytron Chiler
220 kV Source
Hoop VFD
Figure 4-2 Side Module Internal Arrangement (View From Detector Side)
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Portal Inspection System FSM 291-9200-1 Rev. B
4
Bx/FX/TDTx Module Overview
1
2
3
4
5
6
7
1
2
3
4
5
6
7
HVAC Unit
E-Stop Button
Main Circuit Breaker Box
Access Panel
Gulmay
220 kV Source
Hoop VFD
Figure 4-3 Side Module Internal Arrangement (View From Detector Side)
American Science & Engineering, Inc.
Portal Inspection System FSM 291-9200-1 Rev. B
Bx/FX/TDTx Module Overview
5
1
2
3
4
5
6
1
2
3
4
5
6
AC Power Input (Module 1Only)
Main Circuit Breaker Box
220 kV Source
Lytron Chiller
Hoop Board
Gulmay
Figure 4-4 Side Module Internal Arrangement (View from Entrance Side)
Figure 4-5 shows the general arrangement of the top Bx module.
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Portal Inspection System FSM 291-9200-1 Rev. B
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Bx/FX/TDTx Module Overview
1
2
3
4
5
6
7
8
9
10
11
1
2
3
4
5
6
7
8
9
10
11
Power Supply and Controller Board
E-Stop Button
Main Circuit Breaker Box
Main Disconnect
Signal Combiner (Typical, Topshooter Only)
Hoop VFD
220 kV Source
Hoop Board
Gulmay
HVAC Unit
Approach Side Access Panel (Shown Open)
Figure 4-5 Top Module (Topshooter) Internal Arrangement (Typical)
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Portal Inspection System FSM 291-9200-1 Rev. B
Bx/FX/TDTx Module Overview
7
1
2
3
4
5
6
1
2
3
4
5
6
Lytron Chiller
HVAC Unit
Gulmay
220 kV Source
Departure Side Access Panel (Original Design, Shown Open)
Hoop VFD
Figure 4-6 Top Module (Topshooter) Internal Arrangement (Typical)
4.1.2
Module Interior Access
4.1.2.1
Side Modules
Use the access panel (4, Figure 4-3) to obtain internal access to the side modules.
4.1.2.2
Topshooter
There are two methods to gain interior access to the topshooter module. The applicable method
depends on the system configuration. Newer systems integrate a built-in step system to allow
access from the supporting arch structure. Older systems require the removal of a side panel
from either the traffic approach or departure side of the module.
For systems built to the original access configurationd a not modified by the upgrade service
bulletin, gain acces to the topshooter by removing a side panel (5, Figure 4-5).
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Portal Inspection System FSM 291-9200-1 Rev. B
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Electrical Systems
For newer systems and those upgraded by the service bulletin, gain access to the topshooter by
removing a panel on the side opposite the HVAC system.
4.1.3
Heating, Ventilation, and Air Conditioning (HVAC)
The source modules are each equipped with an externally mounted HVAC system (1, Figure 43) to control interior temperature and humidity via a manually controlled inside thermostat
mounted on the HVAC. The unit uses a self-contained heater, fan, compressor, evaporator, and
condenser.
CAUTION: The Portal control system incorporates internal temperature sensors that
shut down the system when the interior temperature of the module exceeds 105°F
(40.5°C).
For schedule maintenance of the HVAC unit, refer to Section B, Preventive Maintenance.
4.2
Electrical Systems
4.2.1
Main Circuit Breaker Box
The Main Circuit Breaker Box serves as the control and distribution point for AC power.
Each module contains a circuit breaker box. Refer to Figure 4-3 for the circuit breaker box location.
Table 4-1 lists key AS&E numbers for the circuit breaker box.
Table 4-1 Circuit Breaker Box AS&E Numbers
4.2.1.1
Number
Description
280-0619-1-1
Part Number
Circuit Breaker Box Exterior and Interior
Figure 4-7 shows the Main Circuit Breaker Box and Main Disconnect.
Figure 4-8 shows the major interior components.
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Portal Inspection System FSM 291-9200-1 Rev. B
Electrical Systems
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1
2
1
Main Circuit Breaker Box
2
Main Disconnect
Figure 4-7 Main Circuit Breaker and Main Disconnect
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Portal Inspection System FSM 291-9200-1 Rev. B
10
Electrical Systems
2
1
3
10
4
5
5
6
9
7
8
1
2
3
4
5
6
7
8
9
10
Ausxiliary AC Output
CB1
TVSS1
K1
Output Circuit Breakers
K3
Mains Input
Device Outputs and Control
K2
VFD Power
Figure 4-8 Circuit Breaker Box - Component Layout
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Portal Inspection System FSM 291-9200-1 Rev. B
Electrical Systems
4.2.1.2
11
Circuit Breaker “Always On” Systems
Several of the Portal systems are considered “always on,” that is they should have power applied
even during times when the system is not being used for scans. “Always on” is defined as the
OpCon key is in the OFF position (or an E-stop has been pressed), and there is main AC input
from site mains into the CB1 of each circuit breaker box.
Systems that should be “always on” are:
•
All air conditioners
•
Power Supply 1 (PS1) on each Electronics Panel, powering:
- The E-Stop circuit
- Bx Controller
- Traffic board
- EDAQ
- Ethernet switch
- Hoop Board
- TB2
4.2.2
Bx Detectors
The Backscatter Detector array for each module consists of a series of detector housings as
shown in Figure 4-1. On the side modules, housings are mounted along the side wall of the Bx
module on either side of the hoop. On the topshooter, the housings are aligned along the bottom
of the module.
Each housing assembly includes four photomultiplier tubes (PMTs), and a PMT high voltage
power supply.
Table 4-2 lists key AS&E numbers for the Bx detectors.
Table 4-2 Circuit Breaker Box AS&E Numbers
Number
Description
278-0615-1
Bx Detector
Figure 4-9 shows a Bx detector. Figure 4-10 shows a PMT.
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Portal Inspection System FSM 291-9200-1 Rev. B
12
Electrical Systems
1
2
3
1
Detector Housing
2
PMT
3
PMT Power Supply Location (Item Not Shown)
Figure 4-9 Bx Detector
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Portal Inspection System FSM 291-9200-1 Rev. B
Electrical Systems
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Figure 4-10 PMT Tube
System size determines the number of housings. The Z Gantry and truck-size Z Portal have a
total of ten housings, while the car-size Z Portal has only eight. Table 4-3 describes the differences
Table 4-3 PMT Module Layout
4.2.2.1
System
Side Modules
Topshooter
Car-Size Z Portal
2
4
Truck-Size Z Portal
4
4
Z Gantry
4
4
Detector Connection Differences
The diferences in the number of detectors described in Table 4-3 results in different methods of
connecting the detectors. Refer to Figure 4-11 and Figure 4-12.
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Portal Inspection System FSM 291-9200-1 Rev. B
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Electrical Systems
4
9
10
11
5
6
7
8
12
3
4
4
2
1
2
3
4
5
6
7
8
9
10
11
12
13
13
Source 1
Source 2
Source 3
EDAQ
J402
J401
J340
J310
J400
J320
J300
Detector Combiner
Direction of Traffic Flow
Figure 4-11 Car-Size Z Portal Detector Connections
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Portal Inspection System FSM 291-9200-1 Rev. B
1
Electrical Systems
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4
5
6
7
8
9
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12
3
4
4
13
2
1
2
3
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5
6
7
8
9
10
11
12
13
1
Source 1
Source 2
Source 3
EDAQ
J402
J401
J340
J310
J400
J320
J300
Detector Combiner
Direction of Traffic Flow (Z Portal Only)
Figure 4-12 Truck-Size Z Portal and Z Gantry Detector Connections
4.2.2.2
Detector Description
Each detector is composed of four photo-multiplier tubes (PMTs) that are mounted on the detector housing. X-ray photons enter the detector housing and are absorbed by the scintillating
material, which converts them into optical (visible) photons. The PMTs detect the optical pho-
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Portal Inspection System FSM 291-9200-1 Rev. B
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Electrical Systems
tons and convert them into an electrical current. This current (negative with respect to module
ground) in the form of a signal passes out of the detector housing through coaxial cables and into
the PMT junction box located at the rear of the array.
The detectors measure the total amount of X-ray energy scattered by the object being scanned.
The output signals from detector banks are connected to an data acquisition head (EDAQ) processor.
One PMT High Voltage Power Supply (HVPS) (bronze color box) is mounted on each PMT
housing. The PMT HVPS converts 24 VDC to 800 VDC and provides regulated DC to each
PMT. The PMT voltage may be adjusted individually for tuning the system.
4.2.2.3
PMT Junction Box
The PMT junction box is the interface between the EDAQ and the PMTs in the backscatter
detectors. It combines signals from the PMTs and is a pass-through for cables to the EDAQ.
4.2.3
PMT HVPS
The backscatter detectors require a high voltage power source. The high voltage energizes the
photomultiplier tubes (PMTs) in the detectors.
The PMT HVPS converts 24 V DC input via a step up switching voltage regulator that generates
approximately 1050 V. This high voltage buss is regulated down to the output voltages, adjustable through precision 20 turn pots, through four independent linear regulators.
Power on sequencing and fault detection is performed by another circuit as shown in Figure 413.
The output of the PMT HVPS is split across the inputs to two “tuning” boxes equipped with
multiple potentiometers. The potentiometers can be adjusted to vary the output voltage sent to
individual PMTs in the detector assemblies. Adjusting the voltage allows a technician to electrically “tune” the images coming from the detectors.
NOTE: The On/Off switch on the front panel must always be in the ON (up) position during
normal operation.
Refer to the following:
•
Figure 4-13 for the PMT HVPS block diagram.
•
Table 4-4 for PMT Supply general specification.
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Portal Inspection System FSM 291-9200-1 Rev. B
Electrical Systems
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3
2
1
8
9
8
10
8
11
8
12
4
6
5
7
1
2
3
4
5
6
7
8
9
10
11
12
PMT +24VDC In
+24VDC Input
Current Source
High Voltage Supply
DC-DC Power Supplies
Switching Regulator Controller
Power On Sequencing and Protection
Linear Regulator
Detector PMT HV 1
Detector PMT HV 2
Detector PMT HV 3
Detector PMT HV 4
Figure 4-13 PMT HVPS Block Diagram
Table 4-4 PMT Power Supply General Specifications
Specification
Description
Number of Outputs
4
Input
Voltage
+24V DC at ~ 900MA maximum
Connector
RJ45
Output Connectors
HIROSE Electric Inc., DF7-3P-7.92DS
Output Polarity
Negative
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Portal Inspection System FSM 291-9200-1 Rev. B
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Electrical Systems
Table 4-4 PMT Power Supply General Specifications (Continued)
Adjustment
Potentiometers
Output Voltage Range
Output 1
400V to 1000V
Output 2
400V to 1000V
Output 3
400V to 1000V
Output 4
400V to 1000V
Ripple
0.002% DC to 250KHz, 0.005% > 250KHz
PMT Dynode Current
Output 1, Trans
0 to 2mA
Output 2, Back
0 to 2mA
Output 3, Fwd
0 to 2mA
Output 4, Ref
0 to 2mA
Stability
Long Term = 0.1%/8 Hrs, Short Term = 0.01%/10 Min.
Load Regulation
0.1% with 10% load change
Line Regulation
0.1% with 5% input voltage change
Temperatutre
4.2.3.1
Operating
0°C to 45°C (32°F to 113°F)
Storage
-40°C to 70°C (-40°F to 158°F)
Stability
0.02%/°C
Humidity
5 to 95 non-condensing
Size
6.5”x 5”x 1.25” (16.5 cm x 12.7 cm x 3.2 cm) maximum
Indicators
Input power, one per output
Test Points
Minimum number to include input voltage, GND, and scaled
outputs.
Input Power Connector
The PMT power supply uses an eight pin RJ45 jack for DC power input. Table 4-5 lists the pinouts.
Table 4-5 PMT Power Supply Pinouts
Pin
Description
1
+24V DC
2
+24V DC RTN
3
NC
4
NC
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Electrical Systems
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Table 4-5 PMT Power Supply Pinouts (Continued)
4.2.3.2
5
NC
6
NC
7
+24V DC
8
+24V DC RTN
High Voltage Output Connectors
J1, J3, J4, and J5 are Hirose DF7 connector pinouts are listed in Table 4-6.
Table 4-6 PMT High Voltage Output Connectors
Pin
Description
1
5
-> HV Output 1
1
5
-> HV Output 2
1
5
-> HV Output 3
1
5
-> HV Output 4
Centre
Pin 3
4.2.3.3
-> GND
-> GND
-> GND
-> GND
NC
Indicators
The PMT power supply has five LEDs that display the status of the overall board and individual
outputs. These LEDs are listed in Table 4-7
Table 4-7 PMT Power Supply Indicator LEDs
LED
Color
Description
D18
Green
Illuminated during normal operation.
D5
Red
Output 1 Fault LED, illuminated in output deviates from set output
approximately by more than ± 10%
D8
Red
Output 2 Fault LED, illuminated in output deviates from set output
approximately by more than ± 10%
D11
Red
Output 3 Fault LED, illuminated in output deviates from set output
approximately by more than ± 10%
D14
Red
Output 4 Fault LED, illuminated in output deviates from set output
approximately by more than ± 10%
D17
Red
Over Voltage Trip @ -1050 VDC (see schematic).
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Control and Aquisition Electronics
4.3
Control and Aquisition Electronics
4.3.1
Operator Console
The Operator Console (also known as the OpCon or the switch and indicator panel) is an electromechanical device used to turn system power on/off and control X-ray scanning.
4.3.1.1
Component Layout and Connector
Refer to Figure 4-14 and Figure 4-15 for the switch and indicator panel connections.
1
1
25-pin Connector
Figure 4-14 Z Portal Switch and Indicator Panel
1
1
Connector
Figure 4-15 Z Gantry Switch and Indicator Panel
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Portal Inspection System FSM 291-9200-1 Rev. B
Control and Aquisition Electronics
4.3.1.2
Switches and Indicators
Refer to Section 3.3.8, User Interface, Controls, and Indicators for information on the OpCon
switches and indiators.
4.3.1.3
Interconnections
Refer to Table 4-8 for the Z Portal OpCon pin connections.
Table 4-8 Z Portal Op Con J1 Pin Connections
Pin
Function
1
24V in from BX Controller, turning on red opcon scanning lights when scan is taking place
2
24V in from BX Controller, turning on yellow X-ray on lights when X-rays are being generated
from Source 1
5
24V in from BX Controller turning on yellow X-ray on lights when X-rays are being generated
from any source
7
24V out to BX Controllers to be used for supply for BX Controller interlock chain (returns on
J1 through J8 if all are OK)
8
24V in from BX Controller interlock chain in all module stop switches are up and doors are
closed
9
24V out from satisfied BX Controller interlock chain, back to BX Controllers to power Gulmay
HVPS relays
11
24V in from closed BX Controller ESTOP loop (ESTOP buttons in all modules pulled out) to
keep RL1 powered
13
24V out when the key switch is turned fully to the start position, heading to the ESTOP loop in
the moduels
15
24V in from TB2-5 in Module 1, used for the power on sequence
16
24V in from Traffic light terminal block when red traffic arrow is illuminated to light the red
switch button
18
24V in from supply on Traffic board (fused on board) used for green/red button switch supply
19
24V out to Traffic Board telling the PIC the red button has been pressed
20
24V in from Traffic light terminal block when green traffic arrow is illuminated to light the green
switch button
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22
Control and Aquisition Electronics
Table 4-8 Z Portal Op Con J1 Pin Connections
23
24V out to Traffic Board telling the PIC the green button has been pressed
Refer to Table 4-9 for the Z Gantry OpCon pin connections.
Table 4-9 Z Gantry Op Con J101Pin Connections
4.3.2
Pin
Function
1
24V in from closed Bx Controller ESTOP loop (ESTOP buttons in all modules pulled out)
to keep RL1 powered
2
24V out when the key switch is turned fully to the start position, heading to the ESTOP
loop in the moduels
4
OpCon Power Key power to Bx Controller
5
OpCon Power Key momentary power to Bx Controller
7
24V in from Bx Controller, turning on red OpCon X-ray on indicator 1
8
24V in from Bx Controller, turning on red OpCon X-ray on indicator 1
9
24V in from Bx Controller, turning on red OpCon X-ray on indicator 2
10
24V in from Bx Controller, turning on red OpCon X-ray on indicator 2
11
24V in from Bx Controller, turning on green OpCon power on indicator
12
24V in from Bx Controller, turning on green OpCon power on indicator
13
Chassis Ground
14
Chassis Ground
Electronics Panel
Each module contains an electronics panel. The electronics panels contain components that perform different functions and control the image acquisition of the system.
Table 4-10 lists key AS&E numbers for the electronics panel
Table 4-10 Electronics Panel AS&E Numbers
Number
Description
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Portal Inspection System FSM 291-9200-1 Rev. B
Control and Aquisition Electronics
23
Table 4-10 Electronics Panel AS&E Numbers (Continued)
280-0654-1
Bx Electronics Panel Assembly (Mechanical Only)
The layout of each module’s elecronics panel is similar, but vary slightly as noted below:
On the Z Portal, the electronics panel for Module 1 contains two compoents not included in the
panels for modules 2 and 3. These two components are an 8-port ethernet switch (7, Figure 416) and a Traffic board (11, Figure 4-16).
On the Z Gantry, tThe electronics panel for Module 1 contains 8-port ethernet switch (7, Figure
4-17) not included in the panels for modules 2 and 3.
The electronics panel for the topshooter contains a Signal Combiner (5, Figure 4-5) not found in
Modules 1 and 2. The electronics panel for Module 2 does not contain any unique components,
but lacks the 8-port ethernet switch, the traffic board, and the signal combiner.
Refer to Figure 4-16 for the electronics panel layout.
NOTE: For clarity, cables and wires are not shown on Figure 4-16 and Figure 4-17.
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24
Control and Aquisition Electronics
1
2
3
4
5
6
11
1
2
3
4
5
6
7
8
9
10
11
10
9
8
7
PS3
PS2
PS1
TB2
E-Stop
Bx Controller
8-port switch (Module 1 Only)
4-port switch
TB1
EDAQ
Traffic Board (Module 1 Only)
Figure 4-16 Z Portal Electronics Panel (Module 1 Shown)
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Control and Aquisition Electronics
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1
2
3
4
5
6
10
1
2
3
4
5
6
7
8
9
10
9
8
7
PS3
PS2
PS1
TB2
E-Stop
Bx Controller
8-port switch (Module 1 Only)
4-port switch
TB1
EDAQ
Figure 4-17 Z Gantry Electronics Panel (Module 1 Shown)
Individual electronics components may be removed for service or for replacement. These components include:
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4.3.3
Control and Aquisition Electronics
•
EDAQ processes the composite analog signal from the Backscatter detector array into digital
data, averages the data, and sends it to OpCon computer for imaging.
•
Bx Controller Chassis provides control and low voltage power to various components of
the Portal via the Operator Console and Switched 24VDC harnesses. The Controller also
governs system safety interlocks, emergency stop commands, and general system functions.
•
Source Board controls timing of the Hoop X-ray source.
•
24 V Power Supply converts 240 VAC to 24 VDC for use and distribution by the System
Control Chassis.
•
E-Stop, a push-to-set/turn-to-release button which instantaneously shuts down all components of the Portal.
Hoop Board
The hoop board works in conjunction with microcontroller, stepper motor driver, and opto-isolator interface circuits. Table 4-11 lists key AS&E numbers for the hoop board.
Table 4-11 Hoop Board AS&E Numbers
Number
Description
280-2102-1
Schematic
280-2002-1
PCA
280-0647-1
Part Number
The hoop board performs the following functions:
•
Controlling the local hoop’s Variable Frequency Drive (VFD)
•
Synchronizing all of the VFD’s together (master/slave)
•
Processing the hoop sync/reset signals
•
Controlling and monitoring the hoop shutter
Section 9, Diagrams and Schematics includes a functional block diagram of the hoop board. The
diagram identifies the top-level functions of the board.
The source 1 hoop board clock is considered the master clock, and the other two hoops synchronize to the master clock’s signal.
The hoop board is controlled by the Bx controller. Communication between the two is by means
of an RS232 line.
The hoop board communicates with the microcontroller, a stepper motor driver via an RS-232
serial connection interface. See Table 4-12 for hoop board general specifications, Figure 4-18 for
a view of the hoop board connectors, Table 4-13 for adescription of the connectors, and Figure
4-19 for a view of the hoop board layout.
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Control and Aquisition Electronics
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Table 4-12 Hoop Board General Specifications
Specification
Description
Power
+24VDC nominal (20V to 26V)
Connector
Molex Mini-Fit Jr. 6 Pin RT angle
Hoop harness connector
DB37 Female
System harness connector
DB37 Male
Pickoff and Reset connector
DB9 Male
Stepper/Encoder connector
DB15F
Operating Temperature
-18°C to 40°C (0°F to 104°F)
Storage Temperature
-40°C to 70°C (-40°F to 158°F)
Humidity
5 to 95 non-condensing
Size
TBD
Indicators
One per switch input and critical output. See AS&E Drawing
280-2102-1, Schematic, PCA Hoop, Cargosearch
Figure 4-18 Hoop Board Connections
Table 4-13 Hoop Board Connections
Connection
Description
J1
24V power in from PS2 power supply
J2
Interlock signal for hoop speed and shutter control/status
J3
Control signals and status to/from the VFD
J4 (male)
Sync/reset signal out to local EDAQ
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Control and Aquisition Electronics
Table 4-13 Hoop Board Connections (Continued)
J4 (female)
Shutter stepper power/encoder signal
J5 (male)
Sync/reset signal in from sensors
J5 (female)
RS232 comm to BX Controller
J6
VFD Synchronization signals (in)
J7
VFD Synchronization signals (out)
J9
Hoop Pickoff
J16
X-ray Shutter
Figure 4-19 Hoop Board Layout
4.3.3.1
X-Ray Shutter
A small stepper motor actuates the X-ray shutter. An incremental rotary encoder, which is
mounted to the rear shaft of the stepper motor, senses the shutter position. The encoder index
pulse aligns in such a manner when the X-ray shutter opens half-way, the encoder generates an
index pulse.
The index pulse is used to calibrate the software shutter position counter and as a backup the calibration is also controlled by the microprocessor. Every time the microprocessor receives a ris-
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Portal Inspection System FSM 291-9200-1 Rev. B
Control and Aquisition Electronics
29
ing edge from the index pulse circuit, the microprocessor recalibrates the shutter position
counter.
The encoder also generates two incremental pulse streams (CH-A and CH-B) that are used by
the microprocessor to increase or to decrease the software shutter position counter.
A flip flop circuit decodes the CH-A and CH-B signals from the encoder which increase or
decrease the encoder index pulse used by the microprocessor to maintain the shutter position.
The shaft encoder outputs 500 pulses for each revolution of the stepper motor. During power up,
the microprocessor looks for a reference point (home routine) that rotates the shutter a few times
clockwise and then a few times counterclockwise. The reference point check (home routine)
guarantees that the shutter goes through the index pulse position to ensure software position
counter is calibrated.
The encoder outputs are complimentary TTL signals that are terminated on the board and
received via a differential line receiver. The test points 19, 18, and 17 can be used to verify the
encoder signals. You will notice a 90-degree phase shift between the CH-A / CH-B signals. You
will also see one index pulse when the shutter opens or closes.
The shutter control system runs any time it sees an error or difference between the commanded
position and the actual shutter position. This means if you try to move the shutter manually, the
shutter will go back to its last commanded position. Once the shutter is at the commanded position, it goes into a low power state to reduce the heat dissipation on the stepper motor and the
stepper driver IC chip.
4.3.3.2
Pickoff/Reset Sensor Preamp
The hoop has two sensors: Pickoff and a Reset. The pickoff sensor signals the start of a new Xray scan. The reset sensor signals the start of a new hoop revolution.
The sensor operates on a built-in 10K pull-up resistor. When the sensor is not blocked, the sensor output will be high. The sensor transmitted LEDs receive power from the +5V_RLY power
via R5 resistor. The voltage comparator filters the signal for noise and then retransmits the signal via two differential line drivers (U4 and U10) to the source board.
4.3.3.3
Computer Interface
The hoop board interfaces to the PC via an RS-232 interface, running at 38,400 baud rate. The
CPI ASCII protocol is used to send and receive message packets between the PC and the hoop
board. A timeout feature is incorporated into the hoop board that powers down the X-ray subsystem, if the communication is lost for more than 10 seconds.
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4.3.3.4
Control and Aquisition Electronics
Indicators and Test Points
The hoop board is supplied with many LED indicators that can be used during integrations and
troubleshooting. Table 4-14 lists the LEDs.
Table 4-14 Hoop Board LEDs
4.3.4
LED
Description
D3
24V Input
D4
3.3V
D5
5V
D6
5V
D7
5V
D8
5V
D9
3.3V
D28
Command Shutter Open
D55
Hoop Speed Interlock
D62
Slow indicates master, fast indicates slave
VFD Speed Control
The hoop VFD has four pre-programmed motor frequencies (RPM = Frequency x 60) that the
host computer can select. It is factory configured source input and requires +24V DC for activation. The X1 and X2 line are used to select on the four pre-programmed frequencies, using a
binary code (00 = speed1, 01 = speed2, 10 = speed3, and 11 = speed4). The X3 line is used as the
STOP and fault reset line. The FWD line is used to command the VFD to run.
4.3.5
Bx Controller
The Controller consists of two microcontrollers, switching regulators, and simple opto-isolator
interface circuits. The Controller performs the following functions:
•
Operator console interface
•
Power up contractors
•
Switched 24V DC control
•
Computer interface
Table 4-15 lists key AS&E numbers for the Controller.
Table 4-15 Controller AS&E Numbers
Number
Description
280-0651-1
FRU PN
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Portal Inspection System FSM 291-9200-1 Rev. B
Control and Aquisition Electronics
31
Table 4-15 Controller AS&E Numbers (Continued)
280-2000-1
PC Board
280-6210-1
Schematic
See Table 4-16 for Controller PCB general specification.
Table 4-16 Controller General Specifications
Specification
Description
Voltage
+24V DC nominal (20V to 26V)
Connector
MOLEX Mini Fit Jr. 6 pin right angle
System Harness Connector #1
DB37 Female
System Harness Connector #2
DB37 Male
RS232 Connector
DB9 Female
I2C Expansion Port
16 Pin Header
Debug In-Circuit Program Connector
RJ11
Temperature Startup Circuit Operating
-40°C to 70°C (-40°F to 158°F)
Temperature Remaining Circuits
0°C to 40°C (32°F to 104°F)
Temperature Storage
-40°C to 70°C (-40°F to 158°F)
Humidity
5% to 95% RH non-condensing
Size
TBD
Indicators
One per switch and critical output (see schematic
diagram for details).
Figure 4-20 shows an exterior view of the Controller, and Figure 4-21 shows the top view of
the Controller PCB.
Figure 4-22 shows the Controller connections, and Table 4-16 lists the connections.
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Control and Aquisition Electronics
Figure 4-20 Controller
Figure 4-21 Controller PCB – Top View
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Control and Aquisition Electronics
33
Figure 4-22 Controller Connections
Table 4-17 lists the Controller connections, Table 4-18 lists the test points, and Table 4-19 lists
the LEDs.
Table 4-17 Controller Connections
Connections
Description
J1
Hoop Speed / Shutter Interlock
J2
24V in from power supply
J3
24V out to:
• Traffic Board
• EDAQ
• Ethernet Hub
• Hoop Board
• TB2 (TB2-3 & TB2-5)
• TB2 (Relay Terminal 3)
J4
12V in from 12V power supply
J5
Warning Lights
J6
RJ45 Ethernet Communications
J7
Warning Lights
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Control and Aquisition Electronics
Table 4-17 Controller Connections (Continued)
J8
Vehicle Sensors (Traffic Board “start scan”), HVPS & Main Contactor
J9
Door Switch, Stops 1 & 2, E Stop
J10
Safety and Interlock
J11
Safety and Interlock
J12
RS232 to Hoop Board
J13
RS232 to Gulmay, Control & Status
J15
RS232 Debug Port
Table 4-18 Test Points
Test Point
Description
TP47
Stop Switch 1 (entrance end) return
TP 48
Light Loop complete (should read >10.1VDC)
TP49
1st half of Interlock chain complete
TP50
HVPS Contactor (Gulmay Mains power)
TP51
HVPS Enable (Micro Controlled)
NOTE: Test points 52 through 56 are associated with the system warning lights.
TP 52
Shutter Status Open – Local
TP53
Shutter Status Open – Interlink
TP54
X Ray on 1 Local
TP55
X Ray on External
TP56
X Ray on 2 Local
Table 4-19 LEDs
LED
Description
D50
Stop Switch 1, entrance
D52
Stop Switch 2, exit
D54
Shutter Status
D56
Gulmay Contactor
D58
Main Contactor
D60
Red light power
D62
Amber light power
D64
White light power
D66
Gulmay command on
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35
Table 4-19 LEDs (Continued)
4.3.5.1
D68
Gulmay Prewarn on
D70
Gulmay on X-ray 1
D72
Dulmay on X-ray 2
D76
X-ray on status all
D78
Motion (Z Gantry only)
D81
Vehicle sensed
D87
Hoop up to speed (indicates the first half of the interlock chain is complete)
D90
E-Stop, OpCon
D107
Gulmay Enable (micro)
D117
Sutter open requd
Operator Console Interface/Power Up Contactors
The operator console includes a power ON/OFF key switch and a start pushbutton as shown in
Figure 3-17 and Figure 3-18. When the user first pushes the start pushbutton with the key switch
in the ON position, the Controller receives +12V DC power from the genset battery and latches
the start pushbutton to maintain the +12V DC power to the Controller.
The power up process is controlled by the small power-up microcontroller on the Controller.
This microcontroller and its related circuits are rated for wide temperature operations. If the system transfer switch is in the genset mode, the power up sequence is as follows:
•
Main contactor activates
•
Air conditioner activates
The air conditioner runs and brings the internal module ambient temperature to the operating
range of the internal module components. If the module temperature is not within the operating
range, the operator console lamp will flash with a two flash sequence. This indicates the operator
that the system is running and the air conditioner is working to bring the module temperature to
the normal operating range. Once the module temperature reaches the normal operating range,
the power-up microprocessor applies power to the main contactor, which applies power to the
rest of the system.
Anytime during system operation if the Bx module temperature is not within the normal operating range, the computer will give the user a warning and after 5 minutes the operator console
LCD display shuts down - unless resolved within the 5 minutes.
4.3.5.2
Radar Encoder Controls (Z Portal Only)
NOTE: A Doppler Speed Radar is optional equipment and may be substituted for a Radar
Encoder Control.
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Control and Aquisition Electronics
A Radar Encoder Control is tied to the traffic radar unit on the approach side of the Z Portal. The
signals from the radar encoder control are fed into the Bx Controller for buffering and then
retransmitting to the EDAQ for use in special correction.
4.3.5.3
Computer Interface
The Controller board communicates to the PC via an RS-232 interface, running at 38,400 baud
rate. The CP1 ASCII protocol is used to send and receive message packets between the PC and
the Controller board.
NOTE: The command set (form-factor) for the Bx Controller board is factory-configured.
The in-circuit programming connector (6 pin, RJ11) is brought to the connector
PCB card cage. It is accessible for programming during PCB build and for field
programming.
4.3.5.4
Inputs and Outputs
See AS&E Drawing 280-2100-1, Schematic, PW Assy, Bx Controller for details.
4.3.5.5
Indicators and Test Points
The controller PCB is supplied with many LED indicators that can be used during integration
and troubleshooting. See AS&E Drawing 280-2100-1, Schematic, PW Assy, Bx Controller for
details.
4.3.6
Ethernet Data Acquisition (EDAQ) Head
NOTE: The EDAQ unit is labeled DAQ HEAD.
The EDAQ is a single, 2-channel circuit board that processes analog signals from the Backscatter detector array (CH 1). It converts low-level analog signals from the PMTs into digital data,
averages the data , and sends it to a BitFlow board in the OpCon computer for imaging. The
EDAQ board receives timing pulses from the Source Board and uses the pulses to synchronize
the signal sampling with the position of the hoop disk.
The BitFlow card converts the image data to pixel data that are processed by AseInspection software and displayed on the LCD video monitor in the operator console.
Table 4-20 lists key AS&E numbers for the EDAQ
Table 4-20 EDAQ AS&E Numbers
Number
Description
284-1020-1
DAQ Head Assembly
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Portal Inspection System FSM 291-9200-1 Rev. B
Control and Aquisition Electronics
4.3.6.1
37
Chassis Layout and Connectors
See Figure 4-18.
Figure 4-23 EDAQ - Front and Rear Panels
Table 4-21 identifies the connections at the rear of the EDAQ chassis. Also see Figure 4-19 for
the top view of EDAQ circuit board.
Table 4-21 EDAQ Connections
Label
Type
Description
RS-232
DB9
Connects to COM2 on OpCon computer.
RS-422
DB9
Unused
BIT FLOW DATA OUT
SCSI-2
Connects to BitFlow card in the OpCon computer.
LINAC ACTIVITY
RJ45
Unused
WHEEL SYNC
RJ45
Connects to WHEEL SYNC port on Source Board.
DAQ +24V POWER
8-pin
Connects to J104 port on the Bx Controller.
CH1
BNC
Connects to PMTs in Backscatter Detectors.
CH2
BNC
RTD Option - Neutron Detector
Figure 4-24 EDAQ Circuit Board – Top View
4.3.6.2
I/O Connectors
Table 4-22 lists and briefly describes the connectors located on the rear panel of the EDAQ chassis. Figure 4-25 shows the connector locations and pinouts.
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Control and Aquisition Electronics
Figure 4-25 EDAQ Connectors and Pinouts
Table 4-22 EDAQ I/O Connectors
Connector
Type
Label
Description
J1
SCSI-2
bitflow data out
Digital data output of EDAQ.
J2
DB9M
RS-422
Unused
J3
DB9F
RS-232
Used for control and status of the EDAQ.1
J4
BNC
ch2
Unused
J5
BNC
ch1
Channel 1 Analog input from Backscatter
detectors
J6
RJ45
Wheel Sync
When active, sends frame signal to the
BitFlow card
J7
RJ45
linac activity
Unused
J8
8-pin, MateN-Lock
daq +24V power
External power supply to EDAQ
Table 4-23 Pinout – BitFlow Data Out Connector
J1 Pin
Signal
Function
1
DIG_FRAMESYNC_DH
Frame differential high
2
Not used
3
Not used
4
Not used
5
Not used
6
DIG_LINESYNC_DH
Line differential high
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Table 4-23 Pinout – BitFlow Data Out Connector (Continued)
7
Not used
8
DIG_CLOCK_DH
Clock differential high
9
DIGITAL GROUND
Digital ground
10
DIG_DATA15_DH
Data 15 differential high
11
DIG_DATA14_DH
Data 14 differential high
12
DIG_DATA13_DH
Data 13 differential high
13
DIG_DATA12_DH
Data 12 differential high
14
DIG_DATA11_DH
Data 11 differential high
15
DIG_DATA10_DH
Data 10 differential high
16
DIG_DATA9_DH
Data 9 differential high
17
DIG_DATA8_DH
Data 8 differential high
18
DIG_DATA7_DH
Data 7 differential high
19
DIG_DATA6_DH
Data 6 differential high
20
DIG_DATA5_DH
Data 5 differential high
21
DIG_DATA4_DH
Data 4 differential high
22
DIG_DATA3_DH
Data 3 differential high
23
DIG_DATA2_DH
Data 2 differential high
24
DIG_DATA1_DH
Data 1 differential high
25
DIG_DATA0_DH
Data 0 differential high
26
DIG_FRAMESYNC_DL
Frame differential low
27
Not used
28
Not used
29
Not used
30
Not used
31
DIG_LINESYNC_DL
32
Not used
33
DIG_CLOCK_DL
Clock differential low
34
DIGITAL GROUND
Digital ground
35
DIG_DATA15_DL
Data 15 differential low
36
DIG_DATA14_DL
Data 14 differential low
37
DIG_DATA13_DL
Data 13 differential low
38
DIG_DATA12_DL
Data 12 differential low
39
DIG_DATA11_DL
Data 11 differential low
40
DIG_DATA10_DL
Data 10 differential low
41
DIG_DATA9_DL
Data 9 differential low
Line differential low
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Control and Aquisition Electronics
Table 4-23 Pinout – BitFlow Data Out Connector (Continued)
42
DIG_DATA8_DL
Data 8 differential low
43
DIG_DATA7_DL
Data 7 differential low
44
DIG_DATA6_DL
Data 6 differential low
45
DIG_DATA5_DL
Data 5 differential low
46
DIG_DATA4_DL
Data 4 differential low
47
DIG_DATA3_DL
Data 3 differential low
48
DIG_DATA2_DL
Data 2 differential low
49
DIG_DATA1_DL
Data 1 differential low
50
DIG_DATA0_DL
Data 0 differential low
Table 4-24 Pinouts – Serial RS232/RS422 Connectors
J2 Pin
Description
J3 Pin
Description
1
NC
1
NC
2
TX data low
2
Tx Data
3
RCV Data high
3
Rx Data
4
NC
4
NC
5
Signal Ground
5
Signal Ground
6
NC
6
NC
7
TX data high
7
NC
8
RCV data low
8
NC
9
RAW low
9
NC
Table 4-25 Pinouts – J6 Wheel Sync Connector
J6 Pin
Description
1
Not used
2
Not used
3
SRC_WHEELSYNC_DH
4
SRC_SCAN_DH
5
SRC_SCAN_DL
6
SRC_WHEELSYNC_DL
7
Not used
8
Not used
S1
Not used
S2
Not used
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Control and Aquisition Electronics
4.3.6.3
41
Test Points
Table 4-26 lists and briefly describes the important test points located on EDAQ circuit board.
Previous Figure 4-19 shows the test point locations.
Table 4-26 EDAQ Test Points
TP#
Test Point
TP25
Will be low if scan mode is received from the Source Board.
TP30
DCLK
Upon power-up, will have a positive 50nS pulse repeating at the
pixel rate (pixel averaging time).
TP36
FRAME
Will be high when not scanning, and low when a scan is active.
TP37
LINE
Varies, mostly high, and low for 8 pixel times between scan lines.
The minimum length of a scan line equals [(pixel time) x (number of
pixels in the line + 8)].
TP52
CHNL2
Unused
TP54
CHNL1
Analog Backscatter data
SPARE
Grounding this test point causes the internal grayscale test pattern
to be sent when scan mode is active. The GRAY_ACTIVE LED
(LED11) will flash a 2 digit number in Morse code indicating the
version of the code in the Xilinx chip.
TP71
TP111
Grounding this test point resets the Xilinx chip.
TP124
Grounding this point sets the EDAQ for “Internal / External Clock
Mode.”
TP128
TEST_IMAGE
Selects analog input data or the internal grayscale test pattern. If
this test point is open, normal analog data is sent when scan is
active by either shorting TP129 to ground or receiving scan mode
from the Source board. If TP71 is grounded, the internal grayscale
test pattern will be sent when scan mode is active.
TP129
MAN_SCAN
Grounding this test point puts the EDAQ in scan mode. The
GRAY_ACTIVE LED (LED11) will be lit.
TP130
4.3.6.4
Description
Grounding this test point sends Channel 1 low data or Channel 2
high data.
Status LEDs
Table 4-27 lists and briefly describes the important status LEDs located on the EDAQ circuit
board. Previous Figure 4-19 shows the LED locations.
The LEDs are not visible from outside the EDAQ chassis. To view the status LEDs:
•
Remove the screws securing both sides of the EDAQ front panel to the rails of the Electronics Rack.
•
Slide the EDAQ chassis away from the base assembly.
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Control and Aquisition Electronics
•
Remove the top cover of the EDAQ chassis. This requires removing all the flathead screws
visible on the top cover.
Table 4-27 EDAQ Status LEDs
LED#
Name
Description
All illuminate after power is applied to the EDAQ to indicate that
their respective power supply voltage is applied.
LED1 -
LED7
LED8
UC_ALIVE
Continuously flashes to indicate that the microcontroller is alive.
LED9
FPGA CONFIG
Briefly illuminates when power is applied and then extinguishes
itself. If this LED remains illuminated, the EDAQ will not function
and should be repaired or replaced.
LED10
FPGA_ALIVE
Continuously flashes to indicate that the FPGA is alive.
Blinks if in scan mode and the internal test pattern is being sent.
The blink pattern is the FPGA revision number in Morse-code.
Illuminates solid green when the EDAQ receives a command to
scan. This command can be enabled in the following ways:
LED11
GRAY_ACTIVE
-“Scan On” command is received via a serial port.
-“Scan Enable” differential signal on J6 (TIMING IN) is enabled
(brought low). This input is disabled when “internal timing mode”
is selected.
-TP129 “MAN_SCAN” is brought low.
4.3.6.5
Grayscale Generator
The Grayscale Generator can be used to help troubleshoot problems with the EDAQ, problems
with what the EDAQ is feeding, or to start testing a system when the analog input signal is
unavailable.
When a Line Sync is received by the EDAQ, a repeating series of 512 pixel values are sent out
of the digital output, increasing in brightness from 0 to 65407, or almost the entire 16-bit digital
output range. On the next Line Sync, the process repeats except that the first pixel of this line is
the same brightness value as the second pixel from the last line. This repeating process produces
an image of grayscales with diagonal starting points. Since any given line consists of a repeating
series of 512 pixel values, a system set for 512 pixels per line will show a total of 1 grayscale
“wedge” per line. A 1024-pixel system will show a total of two grayscale “wedges” per line.
4.3.6.6
Internal Timing Mode
In this mode, the EDAQ uses internal timing to generate its own Line Syncs when the normal
external Line Syncs are unavailable or are suspect.
Selecting this mode via jumper or the serial port creates an internal Line Sync with a period of
8.752mS per line. The Pixel Averaging (integration) Time is automatically set to 1µS, creating
lines containing 8,752 pixels. The external Scan Bit is disabled in this mode.
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43
With Internal Timing Mode enabled, the scan can only be initiated via the GUI or via a testpoint-jumper.
4.3.6.7
Subsystem Status Screen
The Subsystem Status screen displays operating parameters for the EDAQ and allows an FSE to
run on-board diagnostics. This screen can be accessed from the operator console or a keyboard.
The keyboard/trackball is required to run diagnostics. For additional information on the Subsystem Status screen, refer to Section 4.4, Subsystem Status Screen.
4.3.7
Fuses
4.3.7.1
Bx Controller Circuit Board
NOTE: The Bx Controller fuses are not FRU. Fuse failure requires a complete board
replacement.
The Controller circuit board includes two fuses. If either fuse fails, replace the complete board.
Refer to Table 4-28 for a list of the Controller fuses and their location.
Table 4-28 Bx Controller Circuit Board Fuses
4.3.7.2
Location
Amps
Volts
Size/type
Type
AS&E P/N
Notes
Top right
5
125
VAC
20mm
fast
acting
n/a
Ant-vibration
hard wired
Top right
10
125
VAC
20mm
fast
acting
n/a
Anti-vibration
hard wired
Gulmay CP225 High Voltage Power Supply
The Gulmay CP225 High Voltage Power Supply includes seven fuses. Refer to Table 4-29 for a
list of the Gulmay fuses and their location.
Table 4-29 Gulmay CP225 High Voltage Power Supply
Location
Amps
Volts
Size/type
Type
AS&E P/N
Notes
Front –
FS1, 2, 4,
5
1 amp
250
VAC
20mm
fast acting
11548-0279
Gulmay P/N
F002
Front FS
3
5 amp
250
VAC
20mm
fast acting
11548-0242
Gulmay P/N
F003
Inside FS
6, 7
63 amp
240
VAC
Brtitish
style
Semiconductor
11548-0280
Gulmay P/N
F010
Refer to Table 4-30 for FRU listed fuses.
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X-Ray Generation Systems
Table 4-30 FRU listed fuses
4.4
Amps
Volts
Size/type
Type
AS&E P/N
5 amp
125 vac
20mm
fast acting
11548-0168
5 amp
250 vac
20mm
fast acting
11548-0242
1 amp
250 vac
20mm
delayed
11548-0279
63 amp
240 vac
British Style
11548-0280
Notes
Gulmay P/N F003
Gulmay P/N F010
X-Ray Generation Systems
The X-ray subsystem consists of:
•
“Hoop” X-ray source capable of generating a “flying spot” X-ray beam
•
Mechanical assembly that holds the X-ray tube, cooling jacket, rotating beam source, and the
shutter assembly
•
High voltage power supply (HVPS) for the X-ray tube
•
Control and Aquisition Electronics
NOTE: All electrical connections to the hoop mechanical assembly and the HVPS connect
at the Hoop PLC Chassis. The hoop mechanical assembly and the HVPS have no
electrical connections (other than a ground strap to PLC Chassis) to any other
device or module.
This section describes the hoop, mechanical assembly, and HVPS. For information on the control and aquisition electronics, refer to Section 4.3, Control and Aquisition Electronics.
Table 4-31 lists key AS&E numbers for the X-Ray Generation System
Table 4-31 X-Ray Generation System AS&E Numbers
4.4.1
Number
Description
280-0634-1
Side Module X-Ray Source
280-0648-1
Topshooter X-Ray Source
Hoop X-ray Source
The hoop uses an X-ray tube and rotating collimator to achieve an 82° beam pattern from each
source.
The hoop X-ray source generates an X-ray beam in a “flying spot” pattern that slices through the
target object in a contiguous series of individual scans. The number of scans per inch varies
based on the speed of the target relative to the scan; a speed increase decreases the scans per inch
of the target and reduces image detail.
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X-Ray Generation Systems
45
Figure 4-26 shows an exploded view of a side module hoop. Figure 4-27 shows a topshooter
hoop.
1
3
2
4
5
6
7
13
8
12
10
11
9
1
2
3
4
5
6
7
8
9
10
11
12
13
Safety Shields
Motor
Shutter Assembly
X-ray Tube Housing
Sync/Reset Sensors
X-ray Tube
High Voltage Cable
X-ray Tube Cover
Temperature/Pressure Sensors
Hoop Board
Base
Collimator
Collimator Support Bracket
Figure 4-26 Hoop (Side Module, Exploded View)
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X-Ray Generation Systems
Figure 4-27 Hoop (Topshooter)
4.4.2
Mechanical Assembly
The hoop mechanical assembly is shown in Figure 4-26 with cover removed. Components
include:
4.4.2.1
•
X-ray tube (6, Figure 4-26) and housing (4, Figure 4-26) with integral step actuated shutter
assembly (3, Figure 4-26)
•
Collimater (12, Figure 4-26) (narrows the wide beam output of the X-ray tube)
•
Rotating dish with multiple beam apertures
•
Drive motor (2, Figure 4-26)
•
Base (11, Figure 4-26)
X-ray Tube
The hoop uses a Comet AG MXR-225FB, wide angle, water-cooled X-ray tube (6, Figure 4-26)
pressed-in into the X-ray tube housing (4, Figure 4-26).
Figure 4-26 shows details of the X-ray tube.
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X-Ray Generation Systems
47
2
3
1
1
2
3
X-Ray Window
High Voltage Connection Socket
Water Cooling Conections
Figure 4-28 X-Ray Tube Details
The tube meets the specifications listed in Table 4-32
Table 4-32 X-ray Tube Specifications
Voltage:
220 kV (Unipolar)
Power:
3000 watts (continuous maximum)
Focal Spot Size:
3.0 (IEC336)
Radiation Coverage:
5° x 90°
Target Material:
Tungsten
Target Angle:
15°–22°
Radiation Leakage:
<1000 mR/h
The shutter (Figure 4-29) controls the emission of X-rays by rotating a shaft 90 degrees. The
shutter (5, Figure 4-29) is made from machined tungsten, and connects to a stepper motor (2,
Figure 4-29) by a solid coupling (3, Figure 4-29).
Figure 4-30 shows the X-ray tube, shutter, and housing as an assembly.
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1
2
3
4
5
1
2
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4
5
Encoder
Stepper Motor
Coupling
Bushing
Shutter
Figure 4-29 X-Ray Shutter (Exploded View)
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1
2
3
1
2
3
Shutter Assembly
X-Ray Tube
Housing
Figure 4-30 X-Ray Tube, Shutter, and Housing Assembled
4.4.2.2
X-Ray Tube Cooling
X-ray tube cooling is provided by a separate heat exchanger (commonly called the Lytron
Chiller or Lytron). There is a Lytron in each Bx Module, located next to the HVPS. Cooling
water from the Lytron circulates through the X-ray tube by way of two connections (3, Figure 428)
Refer to Section 4.4.4, Lytron Chiller for more information about the X-ray tube cooling system.
4.4.2.3
Collimator
The collimator (12, Figure 4-26) is a lead X-ray funnel that contains and shapes X-rays from the
tube (6, Figure 4-26) into a particular angle. This angle defines the coveage of the scan area.
Figure 4-31 shows the collimator.
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Portal Inspection System FSM 291-9200-1 Rev. B
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X-Ray Generation Systems
Figure 4-31 Collimator
4.4.2.4
Hoop (Rotating Dish)
The hoop dish is a machined aluminum bowl that has a lead lining along the edge. It covers the
collimator, and controls the emission of X-rays. Figure 4-32 shows the hoop dish, and Figure 433 shows the hoop dish and collimator in place, with the collimator support bracket (13, Figure
4-26) and part of the safety shield removed for clarity.
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Portal Inspection System FSM 291-9200-1 Rev. B
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1
2
3
1
2
3
Aluminum Dish
Aperture
Lead Rim
Figure 4-32 Hoop Dish Assembly
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1
1
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5
Safety Shield (Rear Section)
Hoop Dish
Collimator
Shutter Encoder and Stepper Motor
X-Ray Tube Housing
Figure 4-33 Hoop Dish and Collimator Locations
The fan beam from the X-ray tube emits from apertures in the rotating hoop dish. As the hoop
dish rotates at full RPM, the open apertures in the dish deliver a “flying spot” X-ray beam that
exits the scanning side of the module.
The hoop spins on a main bearing assembly. Normally the main bearing requires no maintenance, and failures are rare, but a main bearing failure may require replacement of the hoop dish.
Figure 4-33 shows the location of the main bearing, with the safety shield removed for clarity.
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Portal Inspection System FSM 291-9200-1 Rev. B
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3
2
1
1
2
3
Drive Motor
Main Bearing
Hoop Dish
Figure 4-34 Main Bearing Location
4.4.2.5
Drive Motor
The drive motor (1, Figure 4-34) spins the hoop. The drive motor is directly coupled to the main
hoop shaft, and is powered by the VFD (7, Figure 4-3 for side modules; 6, Figure 4-5 for the
topshooter).
The motor has sealed bearings, and requires no maintenance.
Refer to Table 4-33 for the drive motor specifications
Table 4-33 Drive Motor Specifications
Specification
Value
Power Rating
2 HP
Current
230 V
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Table 4-33 Drive Motor Specifications (Continued)
4.4.2.6
Frequency
60 HZ
Phase
3
Base
The base (11, Figure 4-26) is the mounting structure for most of the components of the X-ray
generation system. Base design for the side modules is different than for the topshooter.
4.4.2.7
Input Power
The Hoop system is powered from 240VAC (nominal). Input power is directed through the Circuit Breaker Box to the input of the hoop board.
The hoop board controls and distributes power to the following components or sub-systems:
4.4.3
•
Drive hoop VFD inputs
•
Interface to host computer via RS232 running CP1
•
Control shutter stepper motor (stepper driver and encoder read-back)
•
Shielding, door interlocks and X-ray safety circuits
•
Interface to Gulmay HVPS
•
Drive 24VDC X-ray On lamps (warning and active lamps)
•
Buffer pickoff and reset signals used to synchronize system to hoop rotation.
•
Powered from +24VDC
•
The hoop board also supplies 24 VDC and 5 VDC auxiliary-power to other components in
the X-ray sub-system.
High Voltage Power Supply (HVPS)
Danger
The voltages in this power supply are lethal. Observe all precautions detailed
below when servicing this unit.
NOTE: The HVPS is commonly referred to as the Gulmay.
The high voltage power supply (HVPS) is a purchased unit that produces 220 kV at 13mA from
240 VAC single phase input power. It is controlled with hardware interlocks and serial commands.
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It consists of two major parts: the HV generator tank and the converter chassis.
Figure 4-35 shows the HVPS.
1
2
3
1
2
3
Converter Chassis
HVPS Cable Attachment Point
HV Generator Tank
Figure 4-35 Gulmay CP225 HVPS
The HV generator tank contains all the high voltage circuitry required to produce the HV output,
including dual filament isolation transformers. High voltage isolation is achieved via resin
encapsulation and immersion in transformer oil.
The converter chassis sits directly on top of the HV tank. This chassis contains all the electronic
circuitry to produce the controlled 3.2 kW drive for the HV supply along with the drives for the
dual filament transformers.
Power flows from the HVPS to the hoop through the HVPS cable (7, Figure 4-26).
The Gulmay CP225 HVPS is designed to power a unipolar sealed X-ray tube with controlled
dual filament supplies isolated from the high voltage potential. Table 4-34 lists the general specifications for the CP225 power supply.


WARNING: Observe the following precautions when removing the HV cable from the
output socket:
Unplug the power input connector from the converter chassis.
Wait at least two minutes to allow the internal voltages to decay to safe levels.

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Remove the output cable and discharge any residual voltage stored in the
cable capacitance to a suitable protective earth point such as the connector
flange ring on the generator tank.
Refer to Table 4-34 for Gulmay specifications.
Table 4-34 Gulmay CP225 HVPS Specifications
Dimensions
420mm W x 810mm L x 660mm H
(16.5 in. W x 32 in. L x 26 in. H)
Weight
240kg (529 lbs)
Main Supply Input Power
240VAC +10%, 47-63Hz, 6kVA maximum
Auxiliary Supply Input Power
240VAC +10%, 47-63Hz, 100VA
Maximum Output Power
3,200W
Output Voltage
10 to 320kV bipolar
Output Current
30 µamps to 30mA
Regulation – Line Side
Output voltage will vary less than 0.1% with a 10% change in
input line voltage over a period of at least 10 seconds.
Regulation – Load Side
Output voltage and current will vary less than 0.1% over the
operating range.
Filament Output
Large Focal Spot = 8.5V at
4.5A

Small Focal Spot = 6V at 4.5A
Output Connector
200kV (20G C0050)
Interface Connector
DB-25P (male)
The Gulmay connects to the Hoop by means of the HVPS cable (7, Figure 4-26). Figure 4-36
and Figure 4-37 show details of the hoop end of the HVPS cable.
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Portal Inspection System FSM 291-9200-1 Rev. B
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Figure 4-36 High Voltage Power Supply Cable
Figure 4-37 High Voltage Power Supply Cable Tip
Improper installation or a lack of maintenance can cause issues with the HVPS. One common
problem is arcing. Figure 4-38 shows examples of HVPS damage caused by arcing.
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Portal Inspection System FSM 291-9200-1 Rev. B
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Figure 4-38 Examples of HVPS Socket and Cable Arcing
4.4.3.1
Gulmay Safety Interlock Chain
The following switches must be closed before applying power to the Gulmay input stage:
•
Coolant Pressure
•
Coolant Temperature
•
X-Ray Shield Interlock
•
Module Access Panel (Door) Interlock
•
Hoop Motion Interlock
The microprocessor waits for one second and then applies power to the Gulmay interlock relay
(LSI) to allow the system computer to turn on the X-rays. If the communications to the host PC
is lost for more than 10 seconds, the hoop board opens the interlock chain circuits and disables
the X-rays.
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Portal Inspection System FSM 291-9200-1 Rev. B
X-Ray Generation Systems
4.4.3.2
59
Gulmay X-Ray Lamp Control
The power from the Gulmay X-ray lamp output illuminates the system amber warning lights.
The amber lights remain on whenever the Gulmay is generating the high voltage. The amber
lamp signal is combined with the shutter open/ losed status to illuminate the red lights when the
high voltage is on and the shutter is open. Bx Portal Series systems are not equipped with a prewarn signal option.
4.4.3.3
Additional Information
For additional information refer to the following publications:
4.4.4
•
Gulmay LTD, CP Series Technical Manual
•
Gulmay LTD, CP 12-Bit RS Control PCB
•
Gulmay LTD, System Troubleshooting Manual
Lytron Chiller
The Lytron Chiller (Figure 4-39 and Figure 4-40) is a modular system designed to cool the X-ray
tube. The chiller mounts on the floor inside the module. Refer to Figure 4-4 for the Lytron location in the side modules, and Figure 4-5 for the Lytron location in the topshooter.
The Lytron functions as a heat exchanger, and attaches to the X-ray tube using high pressure
lines. The green lines carry coolant from the Lytron to the X-ray tube, and the red lines return
fluid to the Lytron.
Three fans inside the Lytron draw ambirent into the rear of the unit, and blow them across a radiator. Warm air blows out the front of the unit.
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Portal Inspection System FSM 291-9200-1 Rev. B
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Figure 4-39
Air Outlet
Power On/Off Switch
Water Outlet to X-Ray Tube (Green Line)
Water Filter
Coolant Level Sight Gage
Lytron Chiller (Front View)
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Figure 4-40
4.4.4.1
Water Filter
Air Intake and Access Panel
Reservoir Access Panel
AC Power Input and Fuse
Water Return Intake
Lytron Chiller (Rear View)
Reservoir and Coolant
The chiller has a water pump mounted on the bottom rear, and uses a 50/50 mixture of Ethylene
Glycol and distilled water as a coolant. The coolant should be monitored for any leaks on a daily
basis. The Glycol prevents the water from freezing at temperatures down to approximately -40oF
(-40oC).
An internal reservoir contains the coolant.
NOTE: Under normal operating conditions, the system should rarely require coolant.
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Use the sight gage (5, Figure 4-39) on the front of the Lytron to check the coolant level. The
coolant level should be at least 3/4 full. If necessary, access the reservoir through a side panel (3,
Figure 4-40).
To refill the reservoir, the system should be on and pumping.
4.4.4.2
Power
The Lytron draws 220 VAC from the circuit breaker box. The AC plug connects at the rear of the
unit (4, Figure 4-40), and the power recepticle includes a fuse.
There is a power on/off switch on the front of the unit (2, Figure 4-39).
4.4.4.3
Internal Details
Internally, the Lytron contains a circulation pump, the coolant reservoir, , and three fans that
blow ambient air across a radiator.
4.4.4.4
Filters
The Lytron includes two filters.
The water filter (1, Figure 4-40) is mounted externally at the rear of the Lytron. It cleans the
coolant during circulation. This filter is a relatively common “under the sink” type water filter.
The air filter is a common “furnace” type filter, and is located internally behind the rear air
intake access panel (2, Figure 4-40).
4.4.4.5
Maintenance Schedule
For the chiller maintenance schedule, refer to the Section B, Preventive Maintenance.
4.4.5
Hoop Control Electronics
Some of the control electronics are considered part of the x-ray generation system, but are covered elsewhere in this manual. For information on these systems, refer to Section 4.3, Control
and Aquisition Electronics.
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Portal Inspection System FSM 291-9200-1 Rev. B