Lighting circuit trips when heat pump starts

[mac_J]

We have a 15.95kW 1ph 230V 50hz GSHP, which is connected to the power fuse board that has 30 ma RCCB.

It starts up and runs fine.

There is a fuse board for lights, which has a 100ma RCCB, near the power fuse board. The fuse boards are completely separate, the earths are neutralised.

When the heat pump starts up, the 100ma RCCB trips, but when it is reset it stays connected.

Any comments and advice appreciated

Regards

[monkey spanners]

I do some work on a farm and when they have any major electrical problems, shorts and such, it used to trip the power in a house about 500 yards away, was told it was due to the chalky ground.
What this has to do with you problem i don't know, goes back to glass of scotch :o:)

[desA]

We have a 15.95kW 1ph 230V 50hz GSHP, which is connected to the power fuse board that has 30 ma RCCB.

It starts up and runs fine.

There is a fuse board for lights, which has a 100ma RCCB, near the power fuse board. The fuse boards are completely separate, the earths are neutralised.

When the heat pump starts up, the 100ma RCCB trips, but when it is reset it stays connected.

Any comments and advice appreciated

Regards

Does the heat-pump have a soft starter? If not, then you may want to consider installing one.

[freezetech]

could you tell us if the 30ma rcd is working correctly as it been tested

[nike123]

Maybe because of this ( fig. 24 if I correctly interpreted your description):
http://i35.tinypic.com/15x79r7.jpg