Defective null plug?

[MitchM]

When I am trying to calibrate my redox probe, after I insert the null plug, I get a message telling me that the electrode is defective even though the null plug is inserted.
Is the PIII referring to the null plug or the probe?
Could it be a software problem with the expansion box? The expansion box is firmware version 1.03.

Thanks

[Matthias]

when you inserted the null plug and started the calibration - is the shown ADC value stable? if it is not stable the null plug is possibly defective

[MitchM]

ADC value stays stable at 0511.

[Matthias]

then the plug is Ok

does this message appear when calibrated with plug or with probe at 220mV?

[MitchM]

the message appears when calibrated with plug.

[Matthias]

so ProfiLux only calibrated with the null plug and the calibration at 220mV was never started?

does the shown ADC change if you remove the null plug during the calibration and when you connect the probe instead (the question is - is the redox port "alive"?)

after what time does the calibration end? is there still time left (see downcounter) or is the time exceeded?

[MitchM]

- I initiate calibration sequence
- I insert null plug when prompted
- countdown timer starts at 899 seconds and goes down to zero (ADC stable at 0511)
- at that point I get a message that says "electrode is defective"

I'll try removing the null plug and replacing with probe during calibration. I'll post those results next.

[MitchM]

Nothing changes when I remove the null plug and replace it with the probe during calibration.
ADC stays at 0511.

[MitchM]

I don't know if it is a coincidence or not, but when I am trying to calibrate my salinity probe, I am having similar results.
Countdown from 899s, ADC stays at 0511 and final message tells me that the electrode is defective.
Both ports are located on the expansion box.

[Blahenazo]

do you connect the probes to the correct ports ?