Oxygen content issue with Yokogawa EJA ZR22G zirconia in Japan
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Last night, an oxygen concentration analyzer of Japanese brand Yokogawa EJA, model ZR22G, that was used in my workplace suddenly stopped working. The oxygen concentration dropped from its normal value to zero; the screen displayed 4MA and an oxygen concentration of 100%, along with an error alarm. A voltage of -180MV was detected on the CELL+ and CELL- sides. By referring to the manual for troubleshooting, it was determined that the sensor was faulty. I opened the probe and found a ceramic filter element that was slightly damaged, but it was still usable. The heating element and the temperature sensing element were both functioning properly, capable of reaching a temperature of 750 degrees. I still don’t understand what’s causing the problem; I would appreciate any advice from those who are more experienced
Yokogawa’s pressure transmitters are of the EJA series, while those made of zirconia are part of the ZR series. The ceramic filter element mentioned in the probe is the measurement cell in the zirconia probe, and it is a key component of this type of instrument. Since it’s already damaged, get some spare parts.
We use a split-type ZR202S. Turn off the power for once and then turn it on again after 10 minutes. If the problem persists, it means the zirconium magnet is damaged – it’s a component that wears out over time and needs to be replaced
Yes, it’s the measurement cell (zirconium cell); the outer ring on top is damaged, but the interior is still in good condition. I removed it, cleaned it with compressed air, and then reinstalled it. The error message stopped appearing yesterday afternoon, but the voltages at the CELL+ and CELL- terminals are 440 MV, and the oxygen level shown is 0% – which is also incorrect. Normally, 1% should correspond to 67.1 MV. So I tried to recalibrate it using compressed air, but I couldn’t adjust the touchscreen of the ZR402G field instrument at all; there really is no solution!
I tried it; I also attempted the tests several times with power cuts, but it didn’t work. In the end, the power was cut off for an entire night, and even when power was restored the next day, it still didn’t work