More than sensors+automation

How to check the correct function (actual value display) of the device and the coax cable?

The Redox value can also be preset with a pH simulator as for the pH measurement. Then the Redox value can be read from a table contained in the simulator operating instructions. If the simulator is not available, it is possible to directly supply voltage to the device input (BNC socket) and, to check the coax cable, to the end of the cable.
The Rd value can be read on the device according to the voltage.
The device should have the factory settings and should not display any error messages.

Rd-Wert Spannung
-500 -500 mV
0 +0 mV
+500 +500 mV