Can a BS 61008-1 RCCB be used for fault current protection

[Alastair]

I am aware that a BS 61008 can't be used for overload protection but is there a reason that it can't be used for fault current protection.

 

[westward10]

What type of fault.

 

[Alastair]

What type of fault.

PSCC or PEFC

 

[pc1966]

PEFC yes as by its nature it will trip.

PSCC not a chance!

However, even though most RCD will disconnect earth faults in the required time for shock protection (e.g. usual 0.4s TN, 0.2s TT) it will not limit the energy to any reasonable degree. I.e. you could see kA currents for almost 0.2s if delay (type S) which is a lot of I2t

Furthermore many RCCB are only rated to break 1.5kA so the need to be cascaded with a MCB or fuse (up or downstream) that opens faster and so limits the peak current to break if the max prospective current is above their own breaking capability.

 

[Heriberto Batchellor]

i'm interested in this question,I have encountered a similar problem recently, and I am trying to solve it

 

[telectrix]

back it up with a compliant fuse.