Thermo 48i - Page 166

Troubleshooting
Troubleshooting Guides
6-4 Model 48i Instruction Manual Thermo Electron Corporation
Defective chopper motor or cable Check chopper motor cable.
Replace chopper motor.
Alarm - CO Conc. Concentration has exceeded range
limit
Check to insure range
corresponds with expected
value. If not select proper
range.
Concentration low Check user-defined low set
point, set to zero.
Alarm - Zero Check
Alarm - Span Check
Instrument out of calibration Recalibrate instrument.
Alarm - Zero Autocal
Alarm - Span Autocal
Check gas supply. Perform
manual calibration.
Alarm - Motherboard
Status
Alarm - Interface
Status
Alarm - I/O Exp Status
Internal cables not connected
properly
Board is defective
Check that all internal cables
are connected properly.
Recycle AC power to
instrument. If still alarming,
change board.
Table 6-2. Troubleshooting - Alarm Messages, continued
Alarm Message Possible Cause Action