Extension leads with RCD

[koodokan]

If using an extension lead with a built in 30mA RCD plugged in to a socket protected by 30mA RCD in consumer unit,would they trip together in event of cutting through lead ? Not that I've done it,just curious!!!

 

[telectrix]

either one will trip, depends on which is more sensitive. ther is variation either side of the 30mA trip current. try an RCD test, see which one trips.

 

[IQ Electrical]

If using an extension lead with a built in 30mA RCD plugged in to a socket protected by 30mA RCD in consumer unit,would they trip together in event of cutting through lead ? Not that I've done it,just curious!!!

I'll go for both. Even if the upstream device was 100mA I'd still go for both as the fault will most likely be of negligible impedance.