cross-posted from: https://lemmy.dbzer0.com/post/26703241

This diagram is from the service manual of a combi boiler. It’s a flow sensor which detects whether hot water is running, which is then used to trigger on-demand heat and switch a diverter to take radiators out of the loop.

In English, the diagram shows:

  • X ⅔ red wire (+5V)
  • X 2/2 black wire (ground)
  • X 2/6 green wire (signal)

I need to know what those fractions mean. I took the voltage measurements in this video:

I cannot necessarily trust the model in that video to have the same specs as mine. My voltmeter detected 4.68 V on the red input wire showing that the sensor is well fed. The green “signal” wire is supposed to be 0 V at rest and 2 V with water running (or I think the reverse of that is used in some models). In my case the green wire is ~1.33 V at rest and ~0.66 V when water is running. I need to know if these readings are normal as I troubleshoot this problem.

  • unexposedhazard@discuss.tchncs.deEnglish
    0·
    2 months ago

    I dont know how it works in france but here in germany i would expect X 2/2 to just be a label for that contact so you can reference it in a larger diagram. I doubt there is any electrical meaning to it.

      • unexposedhazard@discuss.tchncs.deEnglish
        0·
        2 months ago

        Looking at the attached videos, these are usually connected up with wide rows of quick plug thingies that you can just push cables into. So yeah X indicating its a connector, 2 being the number of the mumber of the connector row and the last number being the pin. Thats how i have seen it done many times.