Detcon P-1000 - Manual (Page 25)

P-1000
Portable Model 1000 H2S Analyzer Rev. 1.0 Page 21 of 24
1. Re-Install ISM.
2. Swap ISM and UTM with another functional pair to determine if ISM or UTM is the problem.
7.1.3 No LCD or 4-20mA signal activity with power applied
Probable Causes: Blown input fuse, Insufficient Operating Voltage, Miss-wired connection.
1. Check/Replace Fuse.
2. Check for correct polarity and verify Operating voltage at the UTM input terminals.
3. Check status of external field wire I.S. Barrier.
4. Replace UTM with functional UTM.
7.1.4 Erratic Sensor Behavior – False/Fault Alarms
Probable Causes: Wet/Intermittent terminals, RFI Interference, Bad Electrochemical Sensor, Target or Cross-
interfering Gases being Detected.
1. Check that ISM collar and rain cover are firmly connected and terminals are not wet.
2. RFI- Use shielded cabling.
3. Re-calibrate sensor and make sure it calibrates successfully and Sensor Life is acceptable.
4. Make sure alarms are not being caused by real gas clouds or cross-interfering gases.
7.1.5 "Span Cal Fault" Message
Probable Causes: Incorrect cal gas delivery, Bad calibration gas, Failing Electrochemical sensor, Inadequate
wait time, Incorrect Cal gas value.
1. Verify that existing Sensor Life% value is not < 25%.
2. Verify that the correct span gas value is entered in the program.
3. Determine if failing Auto Span is due to inadequate signal or inadequate stability .
4. Check cal gas flow, type, concentration, and expiration date (validate cal gas with pull tube).
5. If failing AutoSpan stability test, apply cal gas for 3-5 minutes before executing AutoSpan.
6. If failing AutoSpan signal test, change-out electrochemical sensor and retry AutoSpan .
7.1.6 Clearing "Span Cal" Fault Message
1. This message can be cleared by performing either a successful AutoSpan or AutoZero.
7.1.7 "Zero Cal Fault" Message
Probable Cause: Zero cal before sensor stabilization
1. Use “Zero Air” or N
2
for 5-10 minutes before performing Zero Calibration (Section 4.1)
7.1.8 "Sensor Fault" Message
Probable Cause: Zero baseline has drifted negative, Excessive temperature drift.
1. Re-Calibrate Zero.
2. If "Sensor Fault" is intermittent and correlates with temperature – Contact Detcon.
7.1.9 4-20mA not matching LCD display
Probable Causes: Various
1. Verify adequate operating voltage (> 11.5 VDC).
2. Reads 1.1mA with "Missing Sensor" - unplug and re-install the ISM, and/or cycle power to the unit.
3. Reads 3.5mA – Unit out of Normal Operation, user must clear out of user interface software.
4. Reads > 0.2mA in accurately – 4-20mA should be recalibrated, Contact Detcon for procedure.
7.1.10 "Memory Error" Message
Probable Cause: Faulty memory chip.