78megohms rcd disturbance

[Lee321]

got a recurring rcd tripping once a week

only thing thats not perfect is one lighting circuit with 78meg neutral to earth.

 

[ianmacd]

Are you asking a question there somewhere?

 

[Lurch]

Thanks for letting me know, I was wondering about the IR results for that, kept me up all night that did.

 

[Andy™]

so fix the lighting circuit?

 

[BS3036]

Well, 6 uA is not going to trip an RCD, so first check the functioning of the RCD in isolation, and if it's OK, use an earth leakage clamp meter on each circuit's line and neutral together, to find out which circuit has a high earth leakage, then unplug each appliance on that circuit in turn till you find out which one was causing the high earth leakage.

 

[Lee321]

Are you asking a question there somewhere?

oops sort of bludgeoned into this thread didn't i.

Well, 6 uA is not going to trip an RCD, so first check the functioning of the RCD in isolation, and if it's OK, use an earth leakage clamp meter on each circuit's line and neutral together, to find out which circuit has a high earth leakage, then unplug each appliance on that circuit in turn till you find out which one was causing the high earth leakage.

nice use of micro symbol

 

[Lee321]

[quote name='Andy

 

[Andy™]

might have to just never thought it could be the reason

whilst it may read at X ohms now, but it reduce to much less (or more) depending on movement or dampness, and trip your RCD

 

[Lurch]

nice use of micro symbol

It's a u. This is a micro symbol,

 

[bluetof]

Sorry for being a bit green here.

Do you clamp the meter around the live and neutral of the circuit being investigated.

 

[BS3036]

Sorry for being a bit green here.Do you clamp the meter around the live and neutral of the circuit being investigated.

Yes, that way you measure the difference in current, just the way that the RCD does. However the clamp meter must be able to measure from mA's upwards. Most clamp meters aren't sensitive enough.

 

[bluetof]

Looking at the DiLOG DL6507. seems pretty reasonble.

 

[Lee321]

It's a u. This is a micro symbol,

 

[BS3036]

Looking at the DiLOG DL6507. seems pretty reasonble.