Using 5A relays for Led light bulbs

  • Hello,
    I am currently (since 2015) using Unipi 1.1 and modules of my own design to control the lights in my house.
    But I need to increase the number of inputs/outputs, so I would like to switch to Unipi Neuron, and I am a bit afraid of the relays.

    Both the Neuron and the Extension xS11 have 5A relays and you have a short term overload of 5A listed, but this is exceeded by the inrush current even of regular Led "bulbs". I use Philips and they specify up to 17A. If I look at the transformer for the Led strip, Meanwell 12V/15W, it specifies up to 60A.

    Unipi 1.1 has 10A relays, my modules use an "aliexpress 16A" relays, for both I don't know what the allowed inrush/switch-on current is. But after 6 years of operation, everything seems OK, except for the noname led spotlight in the yard, with which the 16A relay sometimes has trouble tearing-off the contacts.

    I understand that the short term overload which you state, might be something other than inrush, but can you please comment on this? I apologize if you have it listed in the documentation and I missed it.


    Next, should I replace the circuit breakers as well, as I have 10A breakers on the light circuits?

    (Pokud to chápu správně, tak by mi pak elektroinstalace neměla projít revizí, protože na světelných okruzích mám 10A jističe? Bude záležet na revizákovi jestli relé v rozvaděči bude považovat za pevnou součást okruhu, nebo za připojené zařízení?)

    The solution would be to use an external relay, but I would need this in a remote distribution box where will be only Extension. Is possible to have a version of the xS11 which has digital outputs (transistors, not relays)? Because controlling relay by relay sounds like wasting to me.


    Also, are you considering an Extension that has SolidStateRelay? For controlling lights, it might have longer lifetime than a mechanical relay.

    Thanks for response

  • administrators


    We always (even for Unipi 1.1) recommend using a secondary external relay and using the relay on the unit only as a signal relay.

    All available technical parameters for relays on Unipi 1.1 can be found in this article, for Unipi Neuron in this article and for Unipi Extensions in this article.

    It is better to deal with the details of the electrical installation with an installation or inspection technician according to the legislation of your country.

    Best regards,

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