YOKOGAWA ZR22G User Manual page 218

<Locating the failure and countermeasures>
Turn off power to the converter.
Is there any breakage
or poor contact in the wiring to the
converter terminals?
No
Is there any breakage
or poor contact in the wiring to the
detector terminals?
No
Is the sensor extremely
dirty, corroded or broken?
No
Is there any
disconnection or poor continuity
in the wiring between the
detector and
converter?
No
Is an alarm indicated
on the display?
No
End. Carry out calibration.
(2) Alarm 017: Heater Temperature Failure
This alarm occurs if the temperature of the detector heater does not rise during warm-up, or it
drops below 730°C or exceeds 780°C after the warm-up ends.
When alarm 017 occurs, alarm 205 (Cold junction temperature high alarm) and alarm 206 (Cold
junction temperature low alarm) may have been issued at the same time. Be sure to press the
alarm icon on the screen to identify each alarm and check if these alarms are occurring at the
same time. If alarm 205 and alarm 206 are occurring at the same time, the problem might have
been caused by the abnormality in the cold junction system at the detector terminal. In this case,
perform a trouble shooting according to (7) Alarms 205 and 206: Cold junction temperature
alarm in "12.2.2
When alarm 207 and alarm 208 occur at the same time, the problem might have been caused
by the abnormality in the heater unit of the detector. In this case, perform the trouble shooting
according to (8) Alarms 207 and 208: Thermocouple voltage alarm in "12.2.2 Remedies
When Alarms are Generated".
Or if the same problem happens immediately after the power supply starts, the polarity of the
thermocouple output (TC +, TC-) from the detector may be reversed. Check the connection to
detectors.
Causes considered for cases where Alarm 017 occurs independently are shown below.
(1) Faulty heater in the detector (heater wire breakage)
(2) Faulty thermocouple in the detector
(3) Faulty cold junction sensor located at the detector terminal block.
(4) Failure in electrical circuits inside the converter
(5) Heater temperature control overcurrent limiting triggered.
Yes
Replace the damaged
portions.
Yes
Replace the damaged
portions.
Yes
Replace the sensor
assembly.
See Section 11.1.2 for the
replacement procedure.
Yes
Replace the wiring cable.
Replace the sensor
Yes
assembly and temporarily
place the analyzer in the
operating status.
See Section 11.1.2 for the replacement
procedure.
Remedies When Alarms are Generated".
<12. Troubleshooting>
Examine the wiring connection to converter terminals
"CELL+" and "CELL-" Also, check the wiring
connection in the repeater terminal box if it is used.
Examine the wiring connection status to
detector terminals 1 and 2. Also, check that
terminals and cable conductors are not corroded.
Remove the sensor assembly from the detector
and check for the presence of corrosion that may
cause a poor contact between the electrode and
the contact; also, check for dirt. A sensor assembly
in which no abnormality is found may be used again.
However, be sure to use a new metal O-ring and
contact even in such a case.
Remove the wiring conductors from detector
terminals 1 and 2 and short out the removed
conductors. Measure the resistance of these
wiring conductors on the converter side.
The resistance value is normal if it indicates
10 Ω or less.
Turn on the power to the converter and temporarily
place the analyzer in the operating status.
The analyzer operates normally.
Yes
A failure in the detector or
the converter is suspected.
Contact Yokogawa.
IM 11M12G01-02EN 1sh Edition : Mar. 25, 2021-00
12-3
No