Metek 920, Operator'S Manual With Essential Health And Safety Requirements

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5-70 | Model 920 Multi-Gas Analyzer
MS Code MStatus Alarm Type Condition / Description and Suggested Corrective Action
8 4 Warning w PMT Signals
The highest signal from either the
Measure
or
Reference
PMT
(photomultiplier tube) is outside its normal range (5.0–9.84 VDC).
Check these values on the
SIG
screen.
Corrective Action:
Take appropriate safety precautions, open the Electronics Enclo-
sure, and:
• Check the flat cable between the Optical Bench board ( J103 )
and the PMT Buffer for proper connections and inspect it for
damage (cuts, nicks, burn marks, etc.).
• Check the PMT high-voltage connections at the Optical Bench
board ( J101 , J102 ) for proper connections.
• Check the flat cable between the Optical Bench board and the
Micro-Interface board for proper connections and inspect it for
damage (cuts, nicks, burn marks, etc.).
From the User Interface:
• From RUN mode, ensure that Automatic Lamp Control ( ALC ) is
On.
< ‘ALC 0’ = ALC Off >
< ‘ALC 1’ = ALC On >
If the ALC setting is ‘ 0 ’ (Off), change it to ‘ 1 ’ (On) from CFG
mode.
16 5 Fault
f Comm Error
The Microcontroller board cannot establish reliable communica-
tions with the
Host Controller
board.
Corrective Action:
Take appropriate safety precautions, open the Electronics Enclo-
sure, and:
• Check the flat cable between the Host Controller board (on
door inside Electronics Enclosure) and Micro-Interface board
for proper connections and inspect it for damage (cuts, nicks,
burn marks, etc.).
• Ensure the actuators on switch S100 on the Micro-Interface
board are positioned toward the middle of the board. See Figure
5-11 for switch location.

(ALC) RUN

F2 7
CFG

F2 7

Del 1 Ent Ent

See Ribbon Cable
Interconnect drawing in
Appendix A.

See Ribbon Cable
Interconnect drawing in
Appendix A.

(SIG) RUN

F6 1