Thermo Scientific 450iQ Instruction Manual page 193

Thermo Scientific
Problem
Alarm – 5V/24V Step Board
Alarm – Instrument
Temperature
Alarm – Analog I/O
Alarm – Digital I/O
Alarm – Auto Bkg
Cal/Check
Alarm – Auto Span
Cal/Check
Possible Cause
Cable connection Check the cable connections to
that Step POL board.
Fan failure Replace fan if not operating
properly.
Dirty fan filter Clean or replace filter.
Overheating PCB Locate defective PCB reporting
the error and replace if needed.
Defective PCB Replace Analog board.
Defective PCB Replace Digital board.
Incorrect high alarm limit Verify the high limit is correct via
Settings>Status and
Alarms>Concentrations screen.
Instrument background Recalibrate the instrument.
calibration failed
Incorrect high alarm limit Verify the high limit is correct via
Settings>Status and
Alarms>Concentrations screen.
Instrument span Recalibrate the instrument.
calibration failed
Troubleshooting
Troubleshooting Guide
Action
6-9
450iQ Instruction Manual