Air Source pump tripping RCD

[SQUIGGLIES]

Keeping this brief.....................New dwelling.....TT system with 100mA S type rcd protected supply to local board with 30mA RCD. Freelance "engineer" to commission Heat-Pump, as original company disappeared before installation. ASHP worked for a while then tripped the 100mA RCD not the 30mA. Both RCDs tested at nominal trip current and ramp test.....both passed. Selectivity obviously working fine. The supply works with a 3KW kettle and will operate with the ASHP if the earth is disconnected at the ASHP.
There is a very healthy earth to the DB.

Theories and similar experiences appreciated...........................

 

[SQUIGGLIES]

Please send me the details of the ashp and I will do some research.

Sure thank you. LG R32 Monobloc.

 

[marconi]

Sure thank you. LG R32 Monobloc.

What is the electrical power rating of the LG unit?

What is the make and model of type s rcd?

The research I have done does not turn up an RCD type. Indeed, LG literature is silent on any special requirements for type of rcd.

Could you sketch the intake, type S, dbs, final circuits etcetera for me to study please.

I would do some N to E insulation testing of the final circuits If you have not already.

Also, could you measure voltage between N ( at main switch) to E on earth bar with a voltmeter not AVT at no load, light load, medium load and full load? Want to see if N voltage wrt local earth rises by much as loading increases.. Then do an L to E measurement to see how much L falls in voltage with respect to local E as loading increases.

Are you able to temporarily and safely supply LG unit just via its 30mA rcd and mcb ie missing out the type S? Earth to be connected of course.

How long is the final circuit feeding LG unit?

How far away from earth electrode is the LG unit?

Please ramp test the type S RCD when on load apart from LG unit.

 

[marconi]

In LG monobloc manual:

Circuit Breaker Specification Perform the electrical wiring work according to the electrical wiring connection. • All wiring must comply with local requirements. • Select a power source that is capable of supplying the current required by the appliance. • Use a recognized ELCB(Electric Leakage Circuit Breaker) between the power source and the unit. A disconnection device to adequately disconnect all supply lines must be fitted. • Model of circuit breaker recommended by authorized personnel Only. • Select a circuit breaker suitable for the current specification.


This is as helpful as LG get!

 

[SQUIGGLIES]

In LG monobloc manual:

Circuit Breaker Specification Perform the electrical wiring work according to the electrical wiring connection. • All wiring must comply with local requirements. • Select a power source that is capable of supplying the current required by the appliance. • Use a recognized ELCB(Electric Leakage Circuit Breaker) between the power source and the unit. A disconnection device to adequately disconnect all supply lines must be fitted. • Model of circuit breaker recommended by authorized personnel Only. • Select a circuit breaker suitable for the current specification.


This is as helpful as LG get!

That's all I had to work with!

 

[SQUIGGLIES]

What is the electrical power rating of the LG unit?

What is the make and model of type s rcd?

The research I have done does not turn up an RCD type. Indeed, LG literature is silent on any special requirements for type of rcd.

Could you sketch the intake, type S, dbs, final circuits etcetera for me to study please.

I would do some N to E insulation testing of the final circuits If you have not already.

Also, could you measure voltage between N ( at main switch) to E on earth bar with a voltmeter not AVT at no load, light load, medium load and full load? Want to see if N voltage wrt local earth rises by much as loading increases.. Then do an L to E measurement to see how much L falls in voltage with respect to local E as loading increases.

Are you able to temporarily and safely supply LG unit just via its 30mA rcd and mcb ie missing out the type S? Earth to be connected of course.

How long is the final circuit feeding LG unit?

How far away from earth electrode is the LG unit?

Please ramp test the type S RCD when on load apart from LG unit.

Hi, Thank you for being so thorough. I do not have access to site and am just setting off on holiday so bare with me. Can you private message on here?

 

[marconi]

Hi, Thank you for being so thorough. I do not have access to site and am just setting off on holiday so bear with me. Can you private message on here?

Yes.

 

[SQUIGGLIES]

Yes.

Hi Marconi, I have been trying to reply to your private message but am unable because of a Spam / content issue.

 

[Lwhong]

Hi Marconi, I have been trying to reply to your private message but am unable because of a Spam / content issue.

Very interesting, as I just experience the same issue that it trips the 100mA RCD and not 30mA RCD. Trip is from a oil filled air compressor. All measurements did not show anywhere that causes leakage. Did or have you found the fault?