Redundant Isolation Switch in combination boards (meter + MSB)
Posted: Mon Jan 04, 2021 1:34 pm
Under Orion's network for Christchurch, you are required to provide overload protection for mains and also a isolation device before the meter
Usually this is in the form of a 63A MCB in the meter enclosure before the meter and then the meter feeds off to the MSB and MS (din mount isolation switch)
I've seen this set up replicated in combined boards with a 63A MCB isolation switch before the meter and then a main switch after feeding everything else, I personally feel the 2 devices aren't needed and you could simply make your 63A MCB before the meter your main switch and omit the other device, I think it's done this way just out of habit of them being separate usually and people not actually thinking about the change in situation
As far as I'm aware there's nothing that says a meter cant be after the main switch but more so that they are allowed to be before
This single device (63A MCB) ticks all the boxes to me, it gives a main switch, overload protection for the mains and a isolation device for the meter but I'm just wondering if anyone can fault me here?
Usually this is in the form of a 63A MCB in the meter enclosure before the meter and then the meter feeds off to the MSB and MS (din mount isolation switch)
I've seen this set up replicated in combined boards with a 63A MCB isolation switch before the meter and then a main switch after feeding everything else, I personally feel the 2 devices aren't needed and you could simply make your 63A MCB before the meter your main switch and omit the other device, I think it's done this way just out of habit of them being separate usually and people not actually thinking about the change in situation
As far as I'm aware there's nothing that says a meter cant be after the main switch but more so that they are allowed to be before
This single device (63A MCB) ticks all the boxes to me, it gives a main switch, overload protection for the mains and a isolation device for the meter but I'm just wondering if anyone can fault me here?