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TROUBLESHOOTING & REPAIR PROCEDURES
Model 300E Carbon Monoxide Analyzer
Instruction Manual
190
P/N 04288 Rev: A
Warning
Message
Fault Condition
Possible Causes
FRONT PANEL
WARN
The CPU is unable to
Communicate with the
Front Panel Display
/Keyboard
WARNING
only appears on Serial I/O COM Port(s)
Front Panel Display will be frozen, blank or will not respond.
§
Failed Keyboard
§
I
2
C Bus failure
§
Loose Connector/Wiring
PHOTO TEMP
WARNING
PHT DRIVE
is >2500
mVDC
§
Failed IR Photo-Detector
§
Failed Sync/Demod Board
§
IR Photo-Detector improperly attached to the Sample
Chamber
§
BENCH TEMP
too high.
REAR BOARD
NOT DET
Mother Board not
detected on power up.
WARNING
only appears on Serial I/O COM Port(s)
Front Panel Display will be frozen, blank or will not respond.
§
Massive Failure of Mother Board
RELAY BOARD
WARN
The CPU cannot
communicate with the
Relay Board.
§
I
2
C Bus failure
§
Failed Relay Board
§
Loose connectors/wiring
SAMPLE FLOW
WARN
Sample flow rate is <
500 cc/min or > 1000
cc/min.
§
Failed Sample Pump
§
Blocked Sample Inlet/Gas Line
§
Dirty Particulate Filter
§
Leak downstream of Critical Flow Orifice
§
Failed Flow Sensor/Circuitry
SAMPLE PRES
WARN
Sample Pressure is
<15 in-Hg or
> 35 in-Hg
Normally 29.92 in-Hg
at sea level decreasing
at 1 in-Hg per 1000 ft
of altitude (with no
flow – pump
disconnected).
If Sample Pressure is < 15 in-HG:
§
Blocked Particulate Filter
§
Blocked Sample Inlet/Gas Line
§
Failed Pressure Sensor/circuitry
If Sample Pressure is > 35 in-HG:
§
Blocked Vent line on pressurized Sample/Zero/Span
gas supply
§
Bad Pressure Sensor/circuitry
SAMPLE TEMP
WARN
Sample temperature is
< 10
o
C or > 100
o
C.
§
Ambient Temperature outside of specified range
§
Failed Bench Heater
§
Failed Bench Temperature Sensor
§
Relay controlling the Bench Heater
§
Failed Relay Board
§
I
2
C Bus
SOURCE
WARNING
Occurs when CO Ref is
<1250 mVDC or
>4950 mVDC.
Either of these
conditions will result in
an invalid M/R ratio.
§
GFC Wheel stopped
§
Failed Sync/Demod Board
If Status LED’s on the Sync/Demod Board
ARE
flashing the
cause is most likely a failed:
§
IR Source
§
Relay Board
§
I
2
C Bus
§
IR Photo-Detector
SYNC WARNING
Phase Lock Loop (PLL)
has lost lock on wheel
rotation.
§
GFC Wheel stopped
§
GFC Wheel rotation very slow/dragging
§
Failed Sync/Demod Board
If Status LED’s on the Sync/Demod Board
ARE
flashing the
cause is most likely an a problem with the analyzer’s main
power:
§
Intermittent loss of the power supply too short to
cause a
SYSTEM RESET
warning;