Trip switch

[Smurff]

Hi, my baily pageant 2007 keeps blowing my house rcd, when we were on site a few weeks ago on retiuning to van after a day out found there was no power to van, checked trip switch, all trips facing up as normal but had to reset site switch, this happened twice, each time on returning from a day out, when site rcd reset everything fine using kettle toaster etc, in fact when we go out for the day we always make a point of turning things off,
Ok I know what your gonna say, check your cable !!! anyway when we got home changed to another cable as I'm fortunate enough to be able to store my van on drive and put van on charge, next day took dyson in to give it a clean, plugged in switched on, nothing checked the house and found my rcd had tripped, checked van all trips up as normal , reset house trips and everything fine, surely van rcd would have tripped as well not just house, or does that narrow problem down a bit

 

[Damian]

If there is an electrical problem it will always trip the farthest away trip first, normally leaving the van trips in their normal position.
In your case, the house trip or site trip.

Having had similar problems with customers Bailey vans I would check the trips in the van as I believe one may be faulty and not working as it should do.
If you do not know how to test the breakers, get a mobile engineer to check them out.

 

[Smurff]

If there is an electrical problem it will always trip the farthest away trip first, normally leaving the van trips in their normal position.
In your case, the house trip or site trip.

Having had similar problems with customers Bailey vans I would check the trips in the van as I believe one may be faulty and not working as it should do.
If you do not know how to test the breakers, get a mobile engineer to check them out.

thank you, how would I test each trip,

 

[Damian]

With a very expensive piece of test equipment

 

[Smurff]

With a very expensive piece of test equipment

Ohhhh thought I might get by with my trusty multimeter

 

[bertieboy1]

Hello,
I'm afraid I think Damien's posting reply could have been a bit clearer , I think he means if everything is working correctly and is rated correctly then the RCD device closest to the load (in this case in the caravan) should operate first.If there is an earth fault between the bollard and the caravan eg in the cable or plugs then the caravan RCD device won't see the fault and won't operate,the RCD device on the bollard will see the fault and should operate.
RCD devices come with 3 different standard earth fault ratings - 10mA,20mA and 30mA,this means that the earth fault current has to equal or exceed these values before they start to operate and open the circuit breaker.
If there is a mismatch in discrimination between RCDs - say the bollard RCD device is rated at 10mA and the caravan RCD device is rated at 20mA or 30mA then for an earth fault in the caravan the bollard RCD device should operate first.
RCD devices have a test pushbutton that,when pushed should trip the circuitbreaker.

 

[Damian]

Quote " RCD devices have a test pushbutton that,when pushed should trip the circuitbreaker"
The push button only tests the physical part of the mechanism, it does not test the electrical breaking point, that is it does not imitate an electrical imbalance.

 

[Smurff]

Thank!s now I'm a bit clearer, however the fault happened on site throwing the bollard and not the van internal rcd, and when I got home, I'm fortunate to be able to park on drive, so connected to my house to give it a clean with the dyson, it tripped the house rcd again, ( used a different cable ) not the van rcd, reset house trip and carried on cleaning van with no problem, if there was a fault somewhere why did it let me carry on using my cleaner.

 

[ProfJohnL]

Hello Smurf,

The intermittent and nature and the mobility of your symptoms makes it harder to identify where the problem may lie.

As form contributors cannot initiate and monitor tests accurate diagnosis is almost impossible. So for safeties sake it will be worth having the electrics checked by a competent fitter with the knowledge and test gear.

 

[bertieboy1]

Damien,
I'm afraid your wrong,pushing the test button does introduce an imbalance (connects line to earth through a resistor),
This tests both the electrical and mechanical mechanisms

 

[bertieboy1]

Re my previous comment - sorry my mistake,the test imbalance connection is between line and neutral across the sensing coil so that a test current imbalance is introduced to cause circuit breaker to trip

 

[GStockton]

Quite right but the test button does only a function test. It will work but does not prove the rcd is working within the specified time and current limits, you need a calibrated rcd tester to do this.This applys a fault current of 30 milli amps to simulate a times 1 test,the device should trip within 200 milli secs. then a five times test 250 milli amps is applied device should trip within 40 millisecs. You can allways apply the fault current ramp test, good units will trip at around 25 milli amps applied to a 30 ma device.

Rcd failure is quite rare pos 1 in every 100 I have tested.

 

[xtrailman]

Seeing the op has changed the mains lead, and assuming both leads are ok, i would suggest he now checks the caravan mains socket, and the cable (usually orange) from the socket to the rcd in the fuse box (pdu).
If no fault found, the caravan rcd is suspect.
You need to be looking for a live to neutral fault or a live to earth, or a neutral to earth.
Neutral to earth faults being the most difficult to trace.

 

[Smurff]

Errrrrrrrr thanks guys !!, will prob get a sparky in, on the other hand I've un plugged then plugged back in switched on n off tried different plug sockets, ultrastore, tv, microwave, n so far no trips, could it be a sensertive trip switch at house n site as I said before the actual vans never tripped, I have tested it, I mean pushed button and it did trip, so maybe it was a one off ?????

 

[bertieboy1]

Smurf,
Look for an earth fault not a line to neutral (short circuit) fault.
An RCD device will not trip for an overcurrent fault (overload or short circuit) only an earth fault.
The reason for the test PB is that if you test the RCD successfully the chances are it will trip when an earth fault is detected,this is why regular operation of the test PB is recommended.
Having changed the supply lead and source of connection it looks like your earth fault is between the van and source of supply,the only common component not changed is the male socket on the van - it isn't wet is it?

 

[xtrailman]

Yes i wrote live to neutal fault with out thinking.