YOKOGAWA EXAxt ZR22G, User Manual, Page: 194 / 211

<12. Troubleshooting>
12-13
IM 11M12A01-02E 16th Edition : Mar. 19, 2020-00
(5) Temperature of the detector cell reaches 750°C or more.
12.3.3 Measurements Sometimes Show Abnormal Values
<Cause and Countermeasures>
(1) Noise may be mixing in with the converter from the detector output wiring.
Check whether the converter and detector are securely grounded.
Check whether or not the signal wiring is laid along other power cords.
(2) The converter may be affected by noise from the power supply.
Check whether or not the converter power is supplied from the same outlet, switch, or
breaker as other power machines and equipment.
(3) Poor wiring contact
If there is poor contact in the wiring, the sensor voltage or thermocouple emf (voltage) may
vary due to vibration or other factors.
Check whether or not there are loose points in the wiring connections or loose crimping
(caulking) at the crimp-on terminal lugs.
(4) Combustible components in the sample gas may be getting into the sensor.
If the combustible components show signs of dust, the abnormality may be improved by
mounting a dust-removing filter K9471UA.
(5) There may be a crack in the sensor or leakage at the sensor-mounting portion.
If the indication of concentration varies in synchronization with the pressure change in the
furnace, check whether or not there is a crack in the sensor or whether the sensor flange is
sticking tightly to the probe-attaching face with the metal O-ring squeezed.
(6) There may be leakage in the calibration gas tubing
In the case of a negative furnace inner pressure, if the indication of concentration varies with
the pressure change in the furnace, check whether or not there is leakage in the calibration
gas tubing.