Page 1 of 1
Is 6amp feeding 100amp main ok?
Posted: Wed Nov 11, 2020 8:23 am
by Debutant
If I have a mcb in a consumer unit rated at 6amps which feeds a small enclosure with a 100a main switch am I right in thinking the main switch rating doesn’t matter as it’s protected by the first mcb in the circuit? Cable size is 1mm
Re: Is 6amp feeding 100amp main ok?
Posted: Wed Nov 11, 2020 6:30 pm
by Mr White
So long as anything after the protective device is rated higher that said protective device all is good.
So in your case you have a 6A MCB and 1mm cable, and a100A switch all is well.
Re: Is 6amp feeding 100amp main ok?
Posted: Wed Nov 11, 2020 6:57 pm
by Debutant
Thank you
I’m pretty sure that as long as the upfront/ first device is adequately sized to protect the cable within the installation any other devices or switch rating do not matter.