Univex 5100-02-IT - Manual (Page 29)

Model 5100-02-IT Combustible Gas Sensor Module
Page: 27
7.3 TRANSMITTER REPLACEMENT
The transmitter assembly should be replaced when it is determined that it is unreliable, noisy or cannot be
calibrated. This situation may occur due to age, corrosion or failed components.
To replace the transmitter assembly:
a. Confirm that system power has been removed.
b. Remove the cover of the main enclosure.
c. Unscrew the two thumb screws in the top of the cover plate, lift the assembly and rotate 90
o to relieve the
wiring service loop.
d. Unplug the sensor connector from the transmitter assembly.
e. Plug connector into new transmitter (be sure to match numbers between connector and socket).
f. Restore power and allow a minimum of 2 hours for stabilization before re-calibration.
7.4 SENSOR REPLACEMENT
The gas sensor needs replacement when:
 The “CAL-FAIL” message appears after calibration.
 The sensor output signal is noisy, causing erroneous gas level readings.
 The “Sensor Failure” message displays.
To replace the sensor assembly:
a. Confirm that system power has been removed.
b. Remove the gas sensor module enclosure cover.
c. Unscrew the two thumb screws in the top of the faceplate, lift the transmitter assembly and rotate 90
o to
relieve the wiring service loop.
d. Unplug the sensor connector from the transmitter.
e. Unscrew the old sensor assembly from the enclosure conduit hub. Remove the sensor assembly with its
harness.
f. Install new sensor assembly into conduit hub.
g. Allow the new sensor to stabilize for a minimum of 2 hours and then calibrate using the procedure in
Section 6.
7.5 INSTALLATION INSPECTION
Prior to system start-up or trouble shooting the entire system should be visually inspected. The following are
guidelines for that inspection:
7.5.1.1 CONTROLLER INSTALLATION
• Controller installed in conformance to instruction manual recommendations.
• AC power is correctly grounded.
• Hot AC and relay connections have safety covers installed.
7.5.1.2 SENSOR MODULE INSTALLATION
• Module installation in conformance with this manual.
• Modules accessible for calibration.
• Wiring terminations clean and correct.
7.5.1.3 MOISTURE TRAPS AND RAINSHIELDS
• Conduit seals and drains installed to avoid moisture build up in electronics enclosure. Water
accumulation in sensor module enclosures is a major cause of damage and system failures - take
precautions to seal electrical conduits and provide moisture traps and drains to avoid water damage
• Rain-shields installed where applicable.
7.5.1.4 STANDARD VOLTAGES
• Regulated DC Voltage to be applied to the sensor module must be between 10 VDC and 30 VDC.
7.5.2 INSPECTION AND TROUBLESHOOTING GUIDE
The inspection and troubleshooting guide can be used to step through the system start-up and to determine
the corrective action if a fault occurs.