Caravan tripping

[Roadrunner479]

Hi new to here so here goes.
I have a lunar ultima 2007 model. I have recently fixed the thetford fridge by changing the lcd pcb.
We then went away in it charging the caravan up before going with the fridge on. No power issues at this point.
When we arrived at the site plugged the caravan into the mains. On a 16 amp breaker after half hour the mains tripped out side.
Went out switched back on 10 minutes later it tripped again outside.
Felt the fuse board box in the caravan and it felt warm so let it cool down.
Went to bed resetting the trip with just the fridge on and a hour later it tripped again.
In the middle of the night turned the fridge off and put the heating on after an hour it tripped yet again.
Went out for the day with the fridge on by the time we got back it had tripped yet again.
Took the fuse out of the fuse board for changing the caravan battery and it still tripped.
So tried different hook up sockets at the site with the same issues.
On bringing the caravan back home using the same hook up leed but plunging it into a 13amp 3 pin socket could have everything on for over two hours and a Hoover with no issues not a blown fuse and it not trip the house breaker.
Any ideas out there.

 

[ProfJohnL]

Hello road runner,

Your question leaves a number of details out which would be useful. You tell us the sites bollards trip, but you don't tell us if its the MCB or if its the safety RCD that tripped. The cause for each are very different.

Are you certain the MCB in the bollard was 16A? or could it have been only 10A?

As the problem only arises when you use the caravans EHU lead by its self, it would be sensible to check the plug and socket on the lead have been wired up correctly. Also have the 13A adaptor you use at home checked for correct wiring. It could be the adaptor is preventing the mains from tripping at home.

 

[Roadrunner479]

It was definitely 16 amp I phoned and checked with them.
I use the same ehu lead at home with the 13amp plug adapter on the end of it
I would have to check on the McB or rcd bit

 

[Buckman]

You stated that the fridge was off but heating was on and then it tripped so unlikely to be the fridge. Did you try running the fridge on gas and heater on gas to eliminate those tow out of the equation. Also check the connections on the EHU lead to see if there is any black from arcing as that could cause tripping. Also check all plugs to see if any of them may have been arcing i.e. kettle, Tv etc. You will see a black spot on the plug where it may be pitted. If so more them likely the socket will need to be replaced. We had this happen on our Lunar.

 

[Roadrunner479]

Even with everything off and unplugged it tripped when connected to the electric hook up

 

[ProfJohnL]

I have given this problem some more thought.

We are still very much in the dark, as to what actually tripped, was teh sites MCB or RCD. Depending on which actually tripped is important as it suggests different problem areas.

However the OP has stated that it still tripped when no appliances were apparently running, and this adds some more information, but its still very unclear as to whats actually happening.

One problem that does sometimes cause the reported effect is failed water heater element. where its insulation has deteriorated and it is shorting to earth. This will cause the RCD to trip, and it can be temperature related, so it may take several minutes of operation before it trips.

But if it was turned off as the OP suggests then that would not cause a trip, so its still a very uncertain situation.

The fact it trips on site where just the EHU cable is used, cold point to a wiring fault in the EHU, but that would normally be an instant trip not delayed. The fact that it does not trip at home, could be due to teh 13A converter that used which some how masks the fault condition.

With so many unknowns, it is almost impossible for us to diagnose the fault condition with any certainty.

Because the OP has not apparently undertaken the basic electrical fault finding tests I suspect he is not an electrician. For that reason its time to stop tinkering and to get the caravan checked by a competent electrician so the fault and remedy can be quickly resolved.