Detcon CXT-IR - Manual (Page 42)

Model CXT-IR
Clearing problem
Probable Causes: Failed sensor, cal gas not removed at appropriate time, problems with cal gas and delivery,
background of target gas.
• The sensor must recover to < 10% of range in < 5 min after Span calibration is complete
• Use bottled air (zero air or N
2
) if there is a known continuous background level.
• Check validity of span gas using pull tube or other means (check MFG date on cal gas cylinder).
• Use proper cal gas regulators and tubing for highly corrosive gases
• Check for obstructions affecting cal gas hitting sensor face (including being wet, blocked, or
corroded). Sensor assemblies use CXT-IR series splashguard adapter assembly with integral filter.
Clean or replace if necessary.
• Replace the plug-in combustible sensor.
Poor Calibration Repeatability
Probable Causes: Failed sensor, use of wrong cal gas or problems with cal gas and delivery, interference gases.
• Check validity of span gas with regulator and sample tubing in place using pull tube or other means
(check MFG date on cal gas cylinder).
• Use proper cal gas regulators and tubing for highly corrosive gases (HF, HCI, Cl2, NH3, HBR, F2,
etc.)
• Check for obstructions affecting cal gas hitting sensor face (including being wet, blocked, or
corroded). Sensor assemblies use CXT-IR series splashguard adapter assembly with integral filter.
Clean or replace if necessary.
• Replace the plug-in combustible sensor.
Unstable Output/ sudden spiking
Possible Causes: Unstable power supply, inadequate grounding, or inadequate RFI protection.
• Verify power source is stable.
• Verify field wiring is properly shielded and grounded.
• Contact Detcon to optimize shielding and grounding.
• Add Detcon ꞌs RFI Protection Circuit accessory if problem is proven RFI induced.
Nuisance Alarms
• Check condulet for accumulated water and abnormal corrosion on terminal board.
• If nuisance alarms are happening at night, suspect condensation in condulet.
• Add or replace Detcon ꞌs Condensation Prevention Packet (PN 960-202200-000).
• Investigate the presence of other target gases that are causing cross-interference signals.
• Determine if cause is RFI induced.
Transmitter not responding
• Verify condulet has no accumulated water or abnormal corrosion.
• Verify required batteries are installed and have enough charge to power the sensor.
• Swap with a known-good ITM to determine if ITM is faulty.
Low Battery / Low Voltage Fault
Possible Cause: Lithium Ion batteries are depleted.
• Change out all three of the Lithium Ion non-rechargeable ‘C’ size batteries with new batteries.
NOTE
Contact the Detcon Service Department for further troubleshooting assistance at
281-367-4100.
CXT-IR Instruction Manual Rev. 1.6 Page 38 of 44