Rcd ramp testing

[Fletch]

Can someone tell me when and why would I need to do this test?

Thanks in advance.

 

[Doc Hudson]

There is no specific requirement in the regs. But for fault diagnostics, if you think an RCD may be oversensitive, to establish if it trips on too low a fault current would be one instance.

Doc H.

 

[Andy™]

not a test required by 7671, but as Doc says, can be useful for fault finding and testing problem RCD's

 

[a1]

A usefull test to have. found on your test meter. (RCD Trip). Mine is a Fluke 1652.

You can just test the circuit (no load), or you can test the circuit with an appliance plugged in and switched on, if you suspect it of having a earth leakage, and this will also show up.

 

[Fletch]

Thanks lads.

 

[paul b b]

A usefull test to have. found on your test meter. (RCD Trip). Mine is a Fluke 1652.You can just test the circuit (no load), or you can test the circuit with an appliance plugged in and switched on, if you suspect it of having a earth leakage, and this will also show up.

what sort of result would you get if you had earth leakage?

 

[Lurch]

what sort of result would you get if you had earth leakage?

A low one.

 

[kme]

+1

 

[Apache]

Obviously?

 

[sparkytim]

If you have some "standing" leakage on the circuit, say 10 m Amp and your tester adds leakage gradually (Ramp test) then you will reach the RCDs tripping threshold (normally around 24 m Amps or so) sooner i.e when your meter reads 14 m A.

It is recommended to test with all loads disconnected to get a true reading for the RCD then you could compare it with a loaded reading to see what standing leakage there is.

Or you could use a leakage clamp meter.