YOKOGAWA ZR202S, User Manual, Page: 144 / 163

<12. Troubleshooting>
12-3
IM 11M13A01-04E
(3) Next, check the resistance of the thermocouple from the probe. Use a multimeter to measure the
thermocouple resistance between terminal 3 (red cable connected) and terminal 4 (white cable
connected) as indicated in Figure 12.3.
The thermocouple is normal if the resistance is 5 Ω or less. If the value is higher than 5 Ω, the
thermocouple wire may be broken or about to break. In this case, replace the heater assembly
(refer to Subsection 11.1.3, “Replacement of the Heater Assembly”).
NOTE
Measure the thermocouple resistance value after the difference between the probe tip temperature
and the ambient temperature decreases to 50°C or less. If the thermocouple voltage is large,
accurate measurement cannot be achieved.
F12-3E.ai
1
2
3
4
YEL
GRN
RED
WHT
Thermocouple
Multimeter
(Ω)
Figure 12.3
(4) If the inspection indicates that the thermocouple is normal, the electronics may be defective.
Consult your local Yokogawa service or sales representative.
Err-03: A/D Converter Failure/Err-04: Writing-to-memory Failure
• A/D Converter Failure
It is suspected that a failure has occurred in the A/D converter mounted in the electrical circuits
inside the converter.
• Writing-to-memory Failure
It is suspected that a failure has occurred in an operation writing to the memory (EEPROM)
mounted in the electrical circuits inside the converter.
<Locating cause of failure, and countermeasures>
Turn off the power to the converter once and then restart the converter. If the converter operates
normally after restarting, an error might have occurred due to a temporary drop in the voltage (falling
below 85 V, the least amount of voltage required to operate the converter) or a malfunction of the
electrical circuits affected by noise. Check whether or not there is a failure in the power supply system
or whether the converter and detector are securely grounded.
If the error occurs again after restarting, a failure in the electrical circuits is suspected. Consult the
service personnel at Yokogawa Electric Corporation.