I'm planning to build a garden room at some point and I have a question about getting power to it. I'd have lighting and sockets plus potentially an electric sauna so it'd need a consumer unit to handle the different circuits. The most convenient place to get power would be from the garage, which has a consumer unit connected back to the main unit in the house where the supply comes in from the street. Is it ok to daisy chain three consumer units like this, assuming the cables and MCBs feeding each downstream unit are all sufficiently rated for the load? I'm getting an electrician to do the wiring but I'd like to know where I'd need to dig the trench to - the garage or back to the house directly.
Daisy-chaining more than two consumer units
- Thread starter sasl
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To be honest without looking first hand at this it’s tricky to comment
Best you find a local competent spark to look at this
Best you find a local competent spark to look at this
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Most places I have worked have an array of distribution units, each one smaller than the next. So the WMDU (weather poof main distribution unit) would likely have 300 amp moulded breakers, the next unit 100 amp, and so on.
However, with domestic, the largest DNO fuse is around 100 amps, and the largest MCB is likely 50 amps, have seen 70 amps, but rare, many boxes limited to 45 amps. So if the garage has a 45 amp MCB then if feeding a garden room, we would want a smaller MCB maybe 40 amps or 32 amps, how much an electric sauna uses I don't know, but as we go up in the load we often need to arrange automatic load shedding.
There is no simple answer, you need to talk to an electrician on site, and let him advise.
However, with domestic, the largest DNO fuse is around 100 amps, and the largest MCB is likely 50 amps, have seen 70 amps, but rare, many boxes limited to 45 amps. So if the garage has a 45 amp MCB then if feeding a garden room, we would want a smaller MCB maybe 40 amps or 32 amps, how much an electric sauna uses I don't know, but as we go up in the load we often need to arrange automatic load shedding.
There is no simple answer, you need to talk to an electrician on site, and let him advise.
Yes - in principle it's fine - but it will depend on how much load will demanded, size of cables throughout that installation, length of cables throughout the installation.
More info needed to give a proper answer.
More info needed to give a proper answer.
It is for "The Electrician" to decide, have you booked them yet?
They will decide the most convenient cost effective option or options, once you have that info you will know which way you are going.
There could be a few different answers that suit or the might be only one realistically.
It might include cable laying and/or load shedding - as previous replies have stated there are many ifs and buts with this limited information.
Talk to Electrician(s) on site first and see your options.
They will decide the most convenient cost effective option or options, once you have that info you will know which way you are going.
There could be a few different answers that suit or the might be only one realistically.
It might include cable laying and/or load shedding - as previous replies have stated there are many ifs and buts with this limited information.
Talk to Electrician(s) on site first and see your options.