GREER Company MICROGUARD 434 Programming manual

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
GREER COMPANY 1918 E. Glenwood Place Santa Ana, CA 92705 Telephone: [phone] FAX: [phone]
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MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
GREER COMPANY 1918 E. Glenwood Place Santa Ana, CA 92705 Telephone: [phone] FAX: [phone]
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The Greer Company
The Greer Company is dedicated to the design and
manufacture of electronic parts created to aid in
crane operation and in the protection of crane
operators and associated personnel. The following
manual has been developed to assist in helping
Service Personnel to understand, locate, and
identify problems that may arise during the operation
of the MicroGuard®434/500 Rated Capacity Limiter
System. Persons using this Manual must be familiar
with this System and with Electrical Servicing. Use
of calibration routines without consultation with the
Greer Company invalidates the warranty.

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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TABLE OF CONTENTS
MICROGUARD ®434/500
RATED CAPACITY LIMITER SYSTEM
TROUBLESHOOTING MANUAL
INTRODUCTION
SERVICE DEDICATION.................................................................... INSIDE FRONT COVER
WHERE TO GO FOR HELP ............................................................................................... 4
SECTION 1
OVERVIEW & PREPARATION ........................................................................................... 5
SECTION 2
PROBLEM FINDER ........................................................................................................... 6
SECTION 3
COMPUTER UNIT............................................................................................................19
SECTION 4
DISPLAY CONSOLE ........................................................................................................31
SECTION 5
REMOTE BAR GRAPH.....................................................................................................35
SECTION 6
EXTENSION REEL...........................................................................................................38
SECTION 7
ANTI TWO-BLOCK FUNCTION .........................................................................................56
SECTION 8
POWER, KICKOUT & BOOM MODE OUTPUTS..................................................................61
SECTION 9
SWING SENSOR .............................................................................................................63
SECTION 10
APPENDIX......................................................................................................................................67

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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When field repairs cannot be made without replacement of a part,
or when troubleshooting advice is needed, one of the following
support numbers should be called:
Link-Belt Construction Equipment Company
Product Support: Lexington, KY
Telephone:[phone]
FAX: [phone]
Greer Company
Service: Santa Ana, CA
Telephone:[phone]
FAX: [phone]
Information provided to support personnel must be accurate and
complete. Please follow the Problem Finder guidelines in
Section 2. Have your crane Model Number and Serial Number
ready. Carefully describe the problem, noting any unusual
System responses that may help us to quickly and effectively
solve your problem.
WHERE TO GO FOR HELP

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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SECTION 1 OVERVIEW & PREPARATION
This Troubleshooting Manual for the MicroGuard®434/500 Rated Capacity Limiter System,
manufactured by the Greer Company and installed on Link-Belt Construction Equipment Company
(LBCE) cranes, provides information and methods for isolating problems that may arise during
operation of the System. Some of these problems can be corrected in the field. Other problems
may require replacement of parts or a return of a part to the factory for servicing. Service personnel
should have prior training and experience in the procedure for operation and setup of this System.
The procedures in this manual, where possible, are based on crane operation and function. A basic
tool kit consisting of wrenches and screwdrivers (flat and Phillips’ blades) will be required to
remove covers and units for inspection. A digital multimeter (DMM) may be required. The DMM
must be capable of measuring DC voltage with a range of 0 volts to ± 50 volts and resolution of 0.1
volts. Resistance range is 0 ohms to 2 megohms. Low cost analog meters are not appropriate
since the input impedance of these meters can give false readings.
BARGRAPH UNIT (OPTIONAL)
P303
J302
P301P300
J305
COMPUTER UNIT
EXTENSION
REEL
P271
COLLECTOR
RING
CRANE
WIRING
HARNESS
CRANE
WIRING
HARNESS
CRANE
WIRING
HARNESS
DISPLAY
CONSOLE
CAB
(INTERNAL)
CAB
(REAR)
BOOM
CRANE CENTER
EXTENSION REEL
SIGNAL CABLE
SWING SENSOR
CABLE
ANTI-TWO BLOCK
SWITCHES &
CONNECTORS
ROD PRESSURE
PORT
PISTON PRESSURE
PORT
FIGURE 1.1 SYSTEM SCHEMATIC OVERVIEW
SECTION 1

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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SECTION 2 PROBLEM FINDER
This PROBLEM FINDER section is designed to aid in determining the location and type of
problem experienced. It is important to follow the recommendations within this section before
contacting the Greer Company.
2.1 SYSTEM SELF-TEST ............................................................................................................ 7
2.2 DISPLAY CONSOLE PROBLEMS......................................................................................... 8
2.3 FAULT REPORTING AND FAULT CODES......................................................................9-14
2.3.1 GROUP “A” FAULT CODES .................................................................................10-11
2.3.2 GROUP “B” FAULT CODES ...................................................................................... 12
2.3.3 GROUP “C” FAULT CODES ...................................................................................... 13
2.3.4 GROUP “D” FAULT CODES ...................................................................................... 14
2.4 “NO FAULT CODE” PROBLEMS....................................................................................15-18
2.4.1 ANTI TWO-BLOCK ALARM ....................................................................................... 15
2.4.2 DISPLAYED LOAD OR RADIUS ERRORS ..........................................................16-17
2.4.3 BOOM MODE SELECTION ....................................................................................... 18
SECTION 2

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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2.1 SYSTEM SELF-TEST
When the power is turned on or when the ”TEST” button is pressed during operation, the computer
and operator’s display console perform a "SELF-TEST," which, as far as is possible, verifies that
the computer, display console, cables, and all remote sensors are working properly.
During SELF-TEST, all display functions are activated, allowing the operator to check whether or
not all indicators are functional.
NOTE: It is important that the indications shown during the SELF-TEST are recognized and fully
understood by the operator in order to aid in correctly determining computer and display
communication problems.
For eight seconds following "power on" or activation of the TEST button (T), the display will show
the following indications:
•All display segments of the bar graph display (B) will be black (ON).
•All display segments of the load, angle, radius, length, and rated capacity windows will be
black (ON), showing “L”.
•The red LED indicators for overload and Anti Two-Block will be illuminated.
•The yellow LED indicator for pre-warning will be illuminated.
•The audible alarm will sound in the crane cab.
•The graphical display window (GD) will show “SYSTEM SELF-TEST IN PROGRESS”
along with the crane model number and the Link-Belt Logo.
If any of the above indications do not occur, continue to SECTION 2.2
DISPLAY CONSOLE PROBLEMS.
FIGURE 2.1 THE DISPLAY CONSOLE
B
GD
T
SECTION 2

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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2.2 DISPLAY CONSOLE PROBLEMS
DISPLAY CONSOLE PROBLEMS are difficult to isolate because of the interaction between the
display console and the computer unit. Failure of either unit, or interconnection of the two units,
causes malfunction of display console indications. No "FAULT" diagnoses of other system
problems can be carried out without the proper function of the display console and it’s
communication with the computer unit.
To solve problems using display console indications, carefully observe the display console at
"power on" and through self-test. Next, use the following chart to help decide the course of action.
PROBLEM ACTION
There are no display console indications at all
when power is turned on. All displays remain
blank and no lights are illuminated.
Refer to SECTION 3.3.
The load, angle, radius, length, and rated
capacity display windows do not show
“,” or the bar graph display window has
missing black segments during the self-test.
Replace display console.
The red or yellow indicator lights do not
illuminate during self-test.
Replace display console.
The display console does not do the self-test.
No words or logical numbers ever appear
after power is turned on. The displays look
jumbled, with lots of missing segments.
Replace display console.
The display console lights are lit. Load, angle,
radius, length and rated capacity show “
,”, but the graphics display remains blank
through and following the self-test.
Display console is OK.
Check connectors at rear of display console.
Refer to SECTION 3.4.
SECTION 2

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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2.3 FAULT REPORTING AND FAULT CODES
SYSTEM FAULT CODES provide one of the most important ways to quickly locate and assess
problems in the MicroGuard® System. Please review this section carefully.
Each time the system is turned on, it goes through a self-testing process lasting eight seconds that
automatically detects most faults in the system. During normal operation, a self-test can be
initiated at any time by pressing the TEST button on the display console.
Many fault conditions are detected without a system self-test.
Faults detected in the system during the self-test, are indicated on the display console in the
following ways:
•The RED OVERLOAD LAMP will illuminate.
•The AUDIBLE ALARM will sound.
•“FAULT” will be displayed in the lower portion of the graphics display.
Fault codes may be displayed within the graphics display on the display console. To view the
codes, press and hold the TEST button and wait for the system to complete the self-test. Do not
release the TEST button. Fault codes will now be displayed in the lower portion of the graphics
display, for as long as the TEST button is held down.
There are four groups of FAULT CODES: A,B,C & D. The function of these groups and a complete
listing of each code is provided on the following pages.
FIGURE 2.2 FAULT CODE DISPLAY SHOWN IN
LOWER PORTION OF GRAPHICS DISPLAY
A000 B0 C00 D00
127(
127(127(
127(


ALWAYS INVESTIGATE FAULTS IN THE “B” AND “C” GROUPS BEFORE
CONTINUING WITH “A” AND FINALLY “D” GROUP FAULTS.
SECTION 2

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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FAULT
CODE
Swing
Sensor
Boom
Angle
Sensor
Extension
Sensor
Tdx 1
Rod
Pressure
Tdx 0
Piston
Pressure
ACTION
000 NONE
001 X
002 X Replace computer
003 X X
004 X Follow SECTION 6.4
005 X X
006 X X Replace computer
007 X X X
008 X Follow SECTIONS 6.6 through 6.8
009 X X
010 X X Replace computer
011 X X X
012 X X Follow SECTION 6.3
013 X X X
014 X X X Replace computer
015 X X X X
No Fault Found
2.3.1 GROUP “A” FAULT CODES
GROUP “A” FAULT CODES REPRESENT FAULTS DETECTED FOR ANALOG SENSORS.
NOTE: CHECK AND REPAIR “B” AND “C” GROUP FAULTS BEFORE PROCEEDING WITH
GROUP "A" FAULT FINDING SENSORS,
The following chart details all the available codes in the left column and the actions to take
in the right column.
SECTION 2

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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FAULT
CODE
Swing
Sensor
Boom
Angle
Sensor
Extension
Sensor
Tdx 1
Rod
Pressure
Tdx 0
Piston
Pressure
ACTION
016 X Follow SECTION 9
017 X X
018 X X Replace computer
019 X X X
020 X X Follow SECTIONS 6.3, 6.4 & 9
021 X X X
022 X X X Replace computer
023 X X X X
024 X X Follow SECTIONS 6.7, 6.8 & 9
025 X X X
026 X X X Replace computer
027 X X X X
028 X X X Follow SECTIONS 6.3, 6.4, 6.7, 6.8 & 9
029 X X X X Replace computer
030 X X X X
031 X X X X X Follow SECTIONS 6.3, 6.4, 6.7, 6.8 & 9
032 &
Higher
Internal Temperature Sensor Fault
Replace Computer Unit
2.3.1 GROUP “A” FAULT CODES continued
SECTION 2

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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FAULT
CODE
FKO
POWER
FEED
A2B
POWER
FEED
DISPLAY
CONSOLE
ADC 2
INTERNAL
FAULT
ADC 1
INTERNAL
FAULT
ACTION
000 NONE
001 X
002 X
003 X X
004 X Replace computer
005 X X
006 X X
007 X X X
008 X See SECTION 7
009 X X
010 X X
011 X X X
012 X X Replace computer
013 X X X
014 X X X
015 X X X X
016 X Check crane circuit breakers, then
See SECTION 3.5.1
017 X X
018 X X
019 X X X
020 X X Replace computer
021 X X X
022 X X X
023 X X X X
024 X X Check crane circuit breakers, then
See SECTION 3.5.1
025 X X X
026 X X X
027 X X X X
028 X X X Replace computer
029 X X X X
030 X X X X
031 X X X X X
No Fault Found
2.3.2 GROUP “B” FAULT CODES
GROUP “B” FAULT CODES REPRESENT FAULTS DETECTED FOR INTERNAL ANALOG
FUNCTIONS AND POWER FEEDS TO THE FUNCTION KICKOUT AND ANTI-TWO BLOCK
SWITCHES.
The following chart details all of the available codes in the left column and the actions to take
in the right column.
SECTION 2

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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FAULT
CODE
SERIAL
EEPROM
CRANE
DATA
RAM DUTY
DATA
PROGRAM ACTION
000 NONE
001 X
002 X Replace system chip
003 X X Follow SECTION 3.5.2
004 X Replace computer
005 X X
006 X X Replace system chip
007 X X X Follow SECTION 3.5.2
008 X Reset crane data
009 X X
010 X X Replace system chip
011 X X X Follow SECTION 3.5.2
012 X X Replace computer
013 X X X
014 X X X Replace system chip
015 X X X X Follow SECTION 3.5.2
016 X Reselect crane setup/configuration
Replace computer, if not resolved
017 X X
018 X X Replace system chip
019 X X X Follow SECTION 3.5.2
020 X X Replace computer
021 X X X
022 X X X Replace system chip
023 X X X X Follow SECTION 3.5.2
024 X X Reselect crane setup/configuration
Reset crane data
Replace computer, if not resolved
025 X X X
026 X X X Replace system chip
027 X X X X Follow SECTION 3.5.2
028 X X X
029 X X X X Replace computer
030 X X X X
031 X X X X X
No Fault Found
2.3.3 GROUP “C” FAULT CODES
GROUP “C” FAULT CODES REPRESENT FAULTS DETECTED FOR
INTERNAL COMPUTER MEMORIES.
SECTION 2

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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2.3.4 GROUP “D” FAULT CODES
GROUP “D” FAULT CODES REPRESENT FAULTS DETECTED
FOR CAPACITY CHART SELECTION.
The following chart details all the available codes in the left column and the actions to take in the
right column.
FAULT
CODE
WRONG
SWING
AREA
WRONG
BOOM
LENGTH
CHART
NOT
FOUND
ACTION
000 NONE
001 X Re-select CRANE SETUP.
Check other sensor faults first.
002 X Boom length is out of range for selected chart.
Check crane setup, boom length and extension
003 X X Re-select CRANE SETUP.
Check other sensor faults first.
004 X Swing to correct working area to select chart.
Check swing sensor zero position.
Follow SECTION 9.5
005 X X Swing to correct working area to select chart.
Check swing sensor zero position.
Follow SECTION 9.5
006 X X Re-select CRANE SETUP.
Check other sensor faults first.
007 X X X Re-select CRANE SETUP.
Check other sensor faults first.
No Fault Found
SECTION 2

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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2.4 “NO FAULT CODE” PROBLEMS
THIS SECTION ADDRESSES THOSE PROBLEMS THAT MAY OCCUR AND ARE NOT
REPORTED BY THE COMPUTER FAULT CODE SYSTEM.
2.4.1 ANTI TWO-BLOCK ALARM (A2B)
This section gives direction to fault diagnosis of A2B alarm problems. For detailed information,
schematic, and voltages, refer to SECTION 7 - ANTI TWO-BLOCK FUNCTION.
•PROBLEM
The Anti Two-Block alarm is continuously ON. Operating the switch at the boom head does not
deactivate the alarm.
This problem suggests an open circuit between the computer A2B input and the A2B switch(es), or
an open circuit between the computer A2B feed and the A2B switch(es)
1. Check extension reel-off cable for damage.
2. Make sure that the Two-Block switches are correctly connected.
3. Check the slip-ring and wiring inside the extension reel.
4. Check the signal cable from the extension reel to the computer. Check connectors (J305).
•PROBLEM
The Anti Two-Block alarm is continuously OFF (safe). De-operating the switch at the boom head,
by lifting the A2B weight does not activate the alarm.
This problem suggests a short circuit between the computer A2B input and the computer A2B feed
somewhere between the computer and the A2B switch(es).
1. Check extension reel-off cable for damage.
2. Make sure that the Two-Block switches are correctly connected.
3. Check the slip-ring and wiring inside the extension reel.
4. Check the signal cable from the reel to the computer. Check connectors (J305).
SECTION 2

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2.4.2 DISPLAYED LOAD OR RADIUS ERRORS
This section gives direction to fault diagnosis of load and radius errors as displayed on the display
console. Load or radius errors may give rise to early or late tripping of overload alarms. Accuracy
of load, radius, length, and angle is determined by the correct installation and maintenance of the
system sensors.
Accuracy of load is governed by the radius accuracy, and the extension, angle, and pressure
sensors.
Accuracy of radius (unloaded) is governed by the extension and angle sensors.
Before continuing, make sure that there are no system faults.
•CHECK BOOM EXTENSION
1. First check that the boom is fully retracted.
2. Check that the extension reel-off cable is correctly layered as a single layer across the
extension reel surface. Any stacking of the cable will cause extension errors when the boom is
fully retracted, causing the System to exceed the 0.5 ft tolerance allowed by the computer for
boom mode selection. If the reel-off cable is stacking on the reel, see SECTION 6.2.
3. Check the zero of the extension sensor at the fully retracted boom position. Enter the
Calibration Mode (SECTION 10.2). Using the “SPAN” command (SECTION 10.4.5), select
sensor No. 2 to view the extension value in feet. The value of extension must be between -0.2
and +0.2, with the boom fully retracted. If the extension value is incorrect, follow the
EXTENSION SENSOR SETUP procedure in SECTION 6.5.
4. Fully telescope the boom and check that the displayed boom length value matches the
maximum length of the boom. If the length value is incorrect, follow the EXTENSION SPAN
calibration procedure in SECTION 6.5.3 .
•CHECK MAIN BOOM RADIUS
1. Fully retract the boom and make sure that the crane configuration is correctly set up.
2. Boom up to about 45° and measure the radius. The measured radius must match the displayed
radius within +/- 0.2 ft. If it does not match, continue to the “CHECK BOOM ANGLE”
procedure. If it does match, continue to “CHECK PRESSURE SENSORS.”
Both procedures are on the next page.
SECTION 2
NOTE
The required accuracy of taped radius measurements is within 0.1 feet.
When taking radius measurements; always use a good quality tape that does not stretch.
The tape should be graduated in feet and tenths of feet. Always measure between the
swing center of the crane and the hook line, using a single part of line, with the crane
centered over front (rough terrain crane) or centered over rear (truck crane).

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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•CHECK BOOM ANGLE
1. Fully retract the boom.
2. Using an inclinometer, set the boom to 0° (zero) and check that the displayed boom angle
value is 0.0°. If the angle value is not 0.0°, follow SECTIONS 6.6, 6.9.1 and 6.9.2.
3. Boom up to a high angle (at least 70°) and measure the angle with the inclinometer. Check that
the displayed angle matches the inclinometer reading within 0.2°. If the displayed angle is
incorrect, follow the angle span calibration procedure in SECTION 6.9.3.
•CHECK PRESSURE SENSORS
The Pressure sensing system is factory calibrated, therefore pressure sensors may not be
individually replaced. Any serious problems will necessitate changing the whole computer unit.
1. Boom fully down until the boom hoist cylinder is fully retracted and on its stop.
2. Loosen both hydraulic connections to the pressure sensors to guarantee zero pressure is
present on the sensors.
3. Enter the CALIBRATION MODE (SECTION 10.2) and use the “PRESSURE MONITOR”
command (SECTION 10.4.9) to view both sensor pressures and nett pressure.
4. Check the PRESSURE values of both sensors. The PRESSURE values should be between
-75 and + 75 PSI. If not, replace the computer
unit.
5. Check the NETT pressure. This should be
between -35 and +35 psi. If not, replace
the computer unit.
SECTION 2
NOTE
The required accuracy of measured angles is within 0.2°.
When taking boom angle measurements; always use a good quality inclinometer. Many
inclinometers are only accurate at 0° (level). Make sure that a reliable position on the
top of the boom is used to measure the angle and that the inclinometer will
provide an accurate reading at 0° (zero) and at 70°.
Pressure
Temperature xx
Piston Pressure yyy
Rod Pressure zzz
Nett Pressure nnn
Exit






FIGURE 2.3 PRESSURE MONITOR

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
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2.4.3 BOOM MODE SELECTION
This section gives direction to fault diagnosis of BOOM MODE selection problems.
The system provides an output from the computer, which drives a solenoid to power the boom
telescope sequence in “A” or “B” modes. The System allows the operator to select either of the two
modes only when the boom is within 0 to 0.5 ft of fully retracted.
•IF “CRANE SETUP” DOES NOT ALLOW SELECTION OF A NEW BOOM MODE
1. First check that the boom is fully retracted.
2. Check that the extension reel-off cable is correctly layered as a single layer across the
extension reel surface. Any stacking of the cable will cause extension errors at fully retracted,
which will exceed the 0.5 ft tolerance allowed by the computer for boom mode selection.
3. If the reel-off cable is stacking on the reel, go to SECTION 6.2.
4. Check the ZERO of the extension sensor at fully retracted. Enter the CALIBRATION MODE
(SECTION 10.2) and use the “SPAN” command (SECTION 10.4.5). Select sensor No. 2 to
view the extension value in feet. The value of extension must be between -0.2 and +0.2, with
the boom fully retracted.
5. If the extension value is incorrect, follow the EXTENSION SENSOR SETUP procedures in
SECTION 6.5.
SECTION 2

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
GREER COMPANY 1918 E. Glenwood Place Santa Ana, CA 92705 Telephone: [phone] FAX: [phone]
19 of 81
GREER COMPANY
GREER COMPANYGREER COMPANY
GREER COMPANY
Crane Systems
SECTION 3 COMPUTER UNIT
The COMPUTER UNIT SECTION defines troubleshooting techniques and limited replacement
procedures.
3.1 COMPUTER UNIT OVERVIEW ...........................................................................................20
3.2 COMPUTER UNIT LAYOUT ................................................................................................21
3.3 INTERNAL STATUS INDICATORS......................................................................................22
3.4 THE COMM INDICATOR .....................................................................................................23
3.5 COMPUTER UNIT REPLACEABLE PARTS.................................................................. 24-26
3.5.1 FUNCTION KICKOUT FUSE (FS2) ..........................................................................24
3.5.2 SYSTEM CHIP (IC16) ...............................................................................................25
3.5.3 COMMUNICATIONS CHIPS (IC1, 2)26
3.6 PRESSURE SENSORS .......................................................................................................27
3.7 REPLACING THE COMPUTER UNIT............................................................................ 28-29
SECTION 3

MicroGuard®434/500 System — Troubleshooting Manual PN W453200 Rev C 08/01/00
GREER COMPANY 1918 E. Glenwood Place Santa Ana, CA 92705 Telephone: [phone] FAX: [phone]
20 of 81
GREER COMPANY
GREER COMPANYGREER COMPANY
GREER COMPANY
Crane Systems
FIGURE 3.1 THE COMPUTER UNIT
3.1 COMPUTER UNIT OVERVIEW
The COMPUTER UNIT, shown in Figures 3.1 and 3.2, is the center of the MicroGuard®434/500
System. The computer unit provides all the necessary functions to read the sensors, control
computations, disconnect functions, and communicate with the display console/internal bar graph.
The computer unit directly connects to the crane wiring harness via a 60-way bulkhead connector.
There are no wiring connections or screw terminals within the unit.
Contained within the unit, are the two hydraulic pressure transducers required to sense pressure
within the boom hoist cylinder. These sensors and the computer are factory pre-calibrated and, as
such, may not be separately replaced in the field.
SECTION 3