CU Compatability

[Mr.Simple]

Hi guys, looking for a bit of help here. I have an old MEM split load CU at a commercial site with the power half protected by an RCD and the other half unprotected. The customer has asked for full RCD protection, but I don't want the hassle of changing the CU and propose to change the MEM breakers (4 of them) to RCBO's. The question is what are the most compatible make of RCBO's for MEM RCB's.

as an after thought, would it be a good idea to create a sticky showing what is compatible with what?

Thanks

 

[GLENNSPARK]

Hi guys, looking for a bit of help here. I have an old MEM split load CU at a commercial site with the power half protected by an RCD and the other half unprotected. The customer has asked for full RCD protection, but I don't want the hassle of changing the CU and propose to change the MEM breakers (4 of them) to RCBO's. The question is what are the most compatible make of RCBO's for MEM RCB's.

as an after thought, would it be a good idea to create a sticky showing what is compatible with what?

Thanks

for a start whats the earthing arrangements?

and drop out the existing RCD....take it along to the wholesalers....match it up...

 

[telectrix]

might not be possible to drop out the RCD. circuits left de-energised at a commercial site won't go down well with client.

@ OP. post a pic. there are various sources for obsolete MCBs, RCDs, etc.

 

[GLENNSPARK]

still need to know what the earthing arrangements are first...before he starts going for the RCBOs..

 

[telectrix]

true. and a Ze reading.

 

[Mr.Simple]

for a start whats the earthing arrangements?

and drop out the existing RCD....take it along to the wholesalers....match it up...

Earthing is TN-C-S, Ze measures as 0.09 Ohms

Currently premises is being "altered" by builders who will need lights on to do their work so cant pull an MCB to take to the wholesalers.

 

[Silly Sausage]

Can't you 'pair up' a couple of circuits in one, appropriately sized, MCB?

 

[GLENNSPARK]

Can't you 'pair up' a couple of circuits in one, appropriately sized, MCB?

but this limits the diversity...

no....get an RCD to fit....

as you may find (as was posted recently) that some manufacturers dont recommend RCBOs (single pole) for TN-C-S either...

 

[telectrix]

if you can fit anything without using a hammer, fit it. otherwise get the local builder.