FAQ00848 of Level Switches FAQ

Check the following points.

(1) Are there any problems with the wiring between the 61F unit and the electrode?
(Are there any breaking, defective tightening or loosening of cables?)

(2) Is the type of liquid different from one that is used when the unit normally operates.

(3) Is an insulating film such as oil formed in the electrodes?

(4) Is a normal-sensitive model used for liquid with high specific resistance?

If the liquid's specific resistance is high, the unit may not operate in general sensitivity (0 to 4kΩoperate resistance). In this case, use a high-sensitive model with the model name ending in suffix H. Generally, a liquid contains less impurity, like distillated water and pure water, its specific resistance becomes higher.
Oil cannot be used with the 61F.