Electric hook up on site

[Huggis]

Hello folks, looking for some advice on electric hook up.

 

We manage to get supply to our van for fridge and lighting etc, however our sockets keep on tripping as soon as we connect the supply when we are on site. This is even before we have anything plugged in.

 

However when we check it at home using our domestic supply all is okay, all the sockets work perfectly well?

 

Many thanks in advance

(?)

[StuartO]

Not clear what you mean by your "sockets keep tripping", could you provide more detail please?  And are you talking about tripping on one particular campsite or several?

 

[Derek Uzzell]

It might also be useful to know the make, model anf year of manufacture of the motorhome invplved.

[thebishbus]

I presume you mean that the hook up supply trips when you connect the hook up lead. If this is the case I suspect that you may have a slight earth leakage somewhere in the motorhome wiring. The reason it works at home could be that you you do not have an earth leakage trip. or that it is not very sensitve.

 

Brian B.

[Huggis]

I have a rapido 997 2007 and when I connect to the supply we have power for everything except the sockets. We have a fuse box in the van and the switch for the sockets trips. Thank you all for your replies

[StuartO]

It could be that you have a domestic-type consumer unit which has RCD protection of the power circuit but not the lights.  The RCD is perhaps tripping because of the way the earth and neutral are connected. Unless you have the requisite testing gear and skills, it's perhaps time to get an electrician to take a look.

[Derek Uzzell]

Huggis

 

It’s likely that your Rapido 997M will be fitted with a 230V ‘consumer unit’ (similar to the one in your house but smaller) that (probably) has a RCD

 

http://www.electricalsafetyfirst.org.uk/guides-and-advice/electrical-items/rcds-explained/

 

and a number of MCBs (Miniature Circuit Breakers) that protect the motorhome’s 230V equipment (eg. fridge, heater, mains sockets, 230V lighting)

 

This is the situation as I envisage it...

 

1: When you have connected to your home’s 230V supply your motorhome’s RCD did not trip, none of the MCBs tripped and the motorhome’s 230V sockets functioned OK.

 

2: When you connected to a campsite’s 230V hook-up your motorhome’s RCD did not trip, but the MCB that controls the 230V sockets did trip even though no equipment was plugged into those sockets. None of the other MCBs tripped and all the 230V equipment they control worked OK.

 

A RCD trips if 'earth leakage’ is identified, but your RCD is evidently not tripping.

 

A MCB will trip if an overload or short-circuit occurs, but the MCB controllong your motorhome’s sockets did not trip when the vehicle was connected to your home’s mains power supply.

 

If there were no ‘socket tripping’ problems previously when the motorhome was connected to the domestic 230V power supply, but now there are when you use a campsite hook-up, the logical explanation is that a fault has developed in the circuit (or the MCB) that relates to the sockets - for example, a connection may have loosened in a socket-outlet causing a short-circuit.

 

If the socket-related MCB is not faulty and is tripping because there’s a short-circuit, it should be anticipated that the tripping will occur irrespective of whether your motorhome is connected to a campsite hook-up or to your home’s mains power-supply. If the MCB were faulty, I would not expect the type of connection (campsite hook-up or domestic power source) to make a difference.

 

StuartO asked earlier “...are you talking about tripping on one particular campsite or several?” You did not answer this, but it’s obviously a significant question.

 

What also needs to be asked is whether you’ve connected your motorhome to your home’s 230V power supply since the campsite ‘tripping’ happened.

[Brian Kirby]

I agree that you should get an electrician to check your van's electrics.

 

I assume that you use a different lead to connect your van to your home supply, since the usual site supply would be via a blue, so called, Euro plug, whereas your home supply is presumably via a standard UK three pin plug, possibly via an adapter cable with a Euro socket to connect to your EHU's Euro plug. However, I can't think of any wiring fault in the adapter, or "home EHU" cable, that would cause an MCB in your van to trip without also tripping the RCD or the mains supply point.

 

As Derek says above, the reason the MCB is tripping is because there is an overload on the circuit (or possibly because the MCB is faulty - possible, but unusual). You've already said this happens before anything is plugged in to a socket, so either, as Derek suggests, a fault has developed in the socket circuit wiring that is resulting in a short when you connect up (vibrations while driving can cause this), or there is something else that you haven't yet discovered that is directly connected to that circuit, and that is the culprit. Is this possible?

 

The usual candidates would be the fridge and the on-board battery charger/12V power supply unit, possibly electric heating/water heating. Does your van have electric heating/water heating? If so, might this be connected to the sockets circuit and have developed a fault?

 

Have you owned the van from new? If not, might a previous owner have made alterations/additions to the wiring?

 

You said the fridge is OK on mains. Don't know which make/model fridge, but if it is an automatic energy selection model, is it possible it is in fact running on gas and not on mains? Have you tried manually switching between energy sources to prove it is running from mains? Otherwise, if the fridge is definitely cooling when on mains, it can probably be discounted.

 

You say you have lights, but even if the charger had failed you should still have lights from the habitation battery, which should have been charging while you were driving. So, might the mains charger be connected into the sockets circuit, and might it have failed so causing a short circuit?

 

If you start checking the possibilities, don't forget to first unplug the mains connection!

 

Final thought. If you have recently acquired the van, unless you bought privately, don't forget the dealer who sold it has responsibility for rectifying defects. Have you contacted them? They will have an electrician, either on their staff, or an independent they turn to for electrical work.

[Derek Uzzell]

Brian

 

The (French) technical specification of a 2007 Rapido 997M can be viewed here:

 

http://www.rapido-camping-car.fr/pdf/fr/Rapido-GT-2007.pdf

 

It appears that a 997M would have, as standard, a Dometic AES Fridge and that the 230V ‘consumer unit’ would have three MCBs (Disjoncteur Magnéto-Thermique 3 zones). It’s also likely that, if Huggis’s motorhome is RHD UK-specification, it would have the optional Truma C-6002EH gas/230V heater. And, of course, a 997M will have a 230V-powered charger for its habitation-battery.

 

So there should be plenty of opportunity to check if none of the 230V equipment is being powered when the motorhome is connected to a 230V power supply (which would suggest it’s the RCD that’s tripping) or it is just the 230V sockets that are inoperative (which would suggest one of the MCBs is tripping).

 

As you rightly say, if an AES fridge were not receiving 230V power it should automatically switch to gas operation, and the lights continuing to work is a red herring unless there are some 230V lights fitted to the Rapido. But a C-6002EH heater won’t work if 230V-operation is selected and no 230V power is present, nor will the battery-charger function.

 

So that’s another back-to-Square-One question that needs asking - is it the RCD that’s tripping, or just one of the MCBs?

[Brian Kirby]

Well done Derek, good find. So yes, three MCBs on the standard French version. I wonder if this is increased to four where the C-6002EH is installed? One might hope it would be.

 

Otherwise, I wonder which circuit that is wired to? The sockets one would expect to be from one circuit (10A MCB?), with the other mains items shared among the other two (with maybe 5A MCB for each).

 

If only three MCBs are present, I'd be looking at whether the electric heating element of the Truma has been wired from the sockets circuit, and whether there is any wiring fault on that circuit (junction boxes etc).

 

We don't know where the consumer unit or the heater are installed, but some are in positions that are vulnerable to loose items such as camping tables or chairs that could damage wiring. Rapido usually seem to do a tidy installation, but who knows what is being carried where?

 

As you say, one is inclined to suspect that what is tripping is, in fact, the RCD and not an MCB, indicating an earth fault, rather than an overload, somewhere within the circuit that feeds the sockets (or anything that has been hard wired into it).

 

I think Shelley should, really, get his van to an electrician familiar with Rapido installations, which is likely to mean a Rapido dealer. It may look a bit more costly than a local electrician, but is likely to prove more cost effective overall, as someone who knows what to expect won't (shouldn't :-)) be charging for a "discovery learning" session before beginning to isolate and correct the fault. The favourite would probably be Wokingham Motorhomes, because of their long association with Rapido, but only if Shelley is within a reasonable distance from them. Others easy to find on the Rapido website, here: http://tinyurl.com/jkvsxgy

 

As said before, if recently bought from a dealer, the van should go back to them for remedy, just in case the fault proves expensive to rectify (dud Truma, for example).

[Derek Uzzell]

Brian Kirby - 2016-07-19 11:36 AM

 

...I think Shelley should, really, get his van to an electrician familiar with Rapido installations...,

 

I’ve assumed Shelley is female, but I agree that it would be wise for someone familiar with motorhome electrics to look at the Rapido and decide what’s happening. I doubt this is a Rapido-specific fault and the cause may well be something simple, but crystal-ball gazing and/or educated guesswork is unlikely to resolve the problem.