Rcbo

[Pete999]

I should know the answer but I don't and have tried google etc so that's out of the way for starters. Reading a post about sockets used for IT equipment and the possible problems caused by RCD tripping due to start up earth leakage, led to think about protecting the circuit with RCBOs with a time delay, problem is I'm not sure if there is such an animal, at least I have never come across one. Question is do they exist?

 

[Welchyboy1]

I should know the answer but I don't and have tried google etc so that's out of the way for starters. Reading a post about sockets used for IT equipment and the possible problems caused by RCD tripping due to start up earth leakage, led to think about protecting the circuit with RCBOs with a time delay, problem is I'm not sure if there is such an animal, at least I have never come across one. Question is do they exist?

I use small 16a rcbo radial circuits to prevent the possibility of this, rather than 32a ring circuits

 

[Richard Burns]

The problem with using a time delay RCD is that they cannot be used as additional protection because the time delay means that you cannot meet the 40 ms disconnection at 5Idn, and since the reason for applying the RCD protection to sockets circuits is for additional protection this precludes time delay.

I believe someone once found a 30mA time delay RCD but I cannot fathom when it would be useful to use one as 100mA would be more appropriate.

 

[Pete999]

The problem with using a time delay RCD is that they cannot be used as additional protection because the time delay means that you cannot meet the 40 ms disconnection at 5Idn, and since the reason for applying the RCD protection to sockets circuits is for additional protection this precludes time delay.

I believe someone once found a 30mA time delay RCD but I cannot fathom when it would be useful to use one as 100mA would be more appropriate.

Thanks Mate