RCBO problem

[SparkJ]

Hello

I was asked to look at a fault in a 1980

 

[Phoenix]

Cant see any reference to you carrying out an IR test on the ring itself, did you do one?

 

[Zeespark]

Do you have a means to measure the mA of each accessory thats plugged into the circuit at all?

AndyGuinness

 

[batty]

You need to get back to basics and test the ring. I really hope you are joking when you say about removing RCBO remember middle aged ladies don't have a great resistance to electric shocks.

 

[pewter]

Is it only the kettles and Iron that make it trip? could they be the problem?

Been 2 middle aged ladies in a house, perhaps they have a middle aged plug in Anne Summers toy, perhaps they could try a battery version

 

[SparkJ]

No did not get time. But it is something that I will do when I get the chance

---------- Post Auto-Merged at 16:32 ---------- Previous post was made at 16:31 ----------

No I don't know how to measure the mA of each accessory

 

[unphased]

Unplug the fridge (favourite RCD tripper) then plug in the kettles and the iron and see if RCD trips. Juggle these appliances around. In my experience it is nearly always an appliance that is the culprit rather thana wiring fault. Especially as its only recently surfaced. If itwas a wiring fault then the RCD would be tripping irrespective of what is plugged in. An insulation test on the circuit would prove the case. My money is on the fridge. :run

 

[apprentice87]

Hi There,

Answered your own question i think...

"However the ladies had two kettles and an iron which would always trip the RCBO even when plugged in to different sockets on the ring"

I would think if there were a wiring fault, it would trip even with NOTHING plugged in. Mind you, i would still do an IR test, as the wiring might only "go funny" when it warms up under load..

john....

 

[batty]

Do you not find though that it may be quicker doing an insulation test at 250v with everything plugged in then that way it will show if it is the appliances you can then unplug them one by one until you find the culprit.

 

[mvkpe1]

I'd PAT test the offending items throw the faulty one in a bin and definitely not remove the RCBO as degrading the safety of the circuit is surely against the regs!

 

[PC Electrics]

My money's on a highish resistance N-E fault. Possibly in the wiring or an appliance that's permanemtly plugged in (fridge, washer etc).

In these cases an IR of the circuit should be at the top of the test list.

 

[sparkytim]

Highly suspect kettles and iron, water and leccy combine to trouble RCDs/RCBOs easily.

 

[PC Electrics]

Highly suspect kettles and iron, water and leccy combine to trouble RCDs/RCBOs easily.

anything with a heating element really.

 

[ProDave]

you need to IR test the kettle and the iron. to rule them out, or condemn them as fault.

Reminds me of when I fitted a new CU once. Next day the customer phoned and said "could you come back and fit 1 socket that wasn't RCD protected as my iron trips it every time." I simply replied "No, buy a new iron"

 

[Doc Hudson]

2 If all of the cabling in the circuit is old colours there is no requirement to fit an RCBO. Remove the item and replace with 32A breaker.

Your assumption is Incorrect. All socket outlets that may reasonable be expected to supply portable equipment outdoors must be RCD protected, was a requirement in the 16th edition, the cable colours were still red black at this time. The rule of thumb was that downstairs sockets in a domestic dwelling were normally put onto an RCD. If you say there is only one ring circuit by default that should be RCD protected. All you need to do is verify the circuit cables electrical integrity. If that is proved satisfactory it must be one or a combination of faulty appliances. Remember statements such as 'it has always previously worked OK' will always be true whenever a fault first manifests itself on an appliance. Appliance or extension leads would be the most logical starting point, or any external wiring susceptible to damp.

Doc H.

 

[Wirybox]

Hi

I recently had a similar problem and found it was the steam iron possibly being overfilled and the excess water getting into the connections. This was in my own house with a 30mA main switch, pat tested the iron and it was fine. Eventually changed the iron for a new one and not a problem since touch wood. Try that before going to any more trouble good luck!

 

[SparkJ]

Thank you for making the point. I stand corrected. I will proceed as you suggest.

 

[SPECIAL LOCATION]

HiI recently had a similar problem and found it was the steam iron possibly being overfilled and the excess water getting into the connections. This was in my own house with a 30mA main switch, pat tested the iron and it was fine. Eventually changed the iron for a new one and not a problem since touch wood. Try that before going to any more trouble good luck!

This is a very common problem...

especially as the Iron gets older...

The plastic water chamber can get a bit brittle and /or get a hairline fracture that only leaks when held in a certain position....

After tripping RCD, they leave the iron for a couple of minutes and the heat drys the damp & it all resets ok..

until the iron is tilted wrong again!

So when empty the Iron tests out OK.

GuinnessGuinness

 

[steptoe]

No did not get time. But it is something that I will do when I get the chance

this still amazes me, folks ask for help with problems and yet they have failed to carry out what would probably be the very first most basic test! headbang

Remember statements such as 'it has always previously worked OK

of course it worked OK before,there was nothing wrong, it doesnt work OK now as there is a fault,

bit the same as, my tyre always held air before, yes, well it doesnt anymore cos its faulty, its called a puncture.

no one questions that

 

[sparkytim]

This reminds me, one of the early Consumer Units I installed with split load RCD protection, 11.30 pm the lady rings me "TV Gone Off, lights ok, can't reset the thingy""

As I got my brain in gear, woken from dreamland, I asked what had she done just before it went off. Oh she says just started the Ironing.

Unplug it and try again, Waits an age and then she returns, Yes OK now it went back up.

Can I finiosh my ironiong now?

No don't use it

Can you come and look at it then? it WAS ok

No you need a new iron.