Consumer unit tripping

[ihawk]

Ok so last night at bedish time the main consumer unit trips (well happy )
So after a process of elimination it turns out to be the summerhouse switch. Good news was I could put the rest of the house back on, as after many attempts to get it restarted it kept tripping maybe 10 to 15 times. I unplugged everything plugged into the sockets on that particular switch and it still kept going off.

So this morning as I sent the Mrs off shopping I thought, time to get screwdrivers out and have a good look at every one of the plates to see if I could find the problem but to my surprise I switched it on this morning just to see if the problem was still there and it come on and everything is working fine and has been for last few hours with no problems, so now I am totally confused.

The installation was done a couple of years ago by me with an armoured cable running the full length (which I checked this morning) and rcd garage consumer unit in the summer house, but this didn't trip as I would've expected it to do if it was a problem with the wiring in the summer house. I have now checked all of the connections and they are all fine should I be worried that this is happened only once, even know I couldn't get it started again at all last night seems very bizarre to me.

 

[ban-all-sheds]

Sounds like there could be an earth fault somewhere between the house and the summerhouse. This is one reason why I never advise putting external installations like that on the main house CU.

Does the external part of the circuit supply anything other than the summerhouse before it gets there, outside sockets for example?

Are all the summerhouse circuits on the RCD? There is no guarantee, BTW, that the RCD there would trip if there was a fault there.

When you had the fault did you try turning the summerhouse CU off?

What readings do you get when you do an IR test on the SWA?

 

[mfarrow]

Is there a junction box in the run to the summer house which has perhaps got damp?

How was the earthing connected for the summer house circuit? Did you gap it or run it all the way through? If the latter you may be able to move the circuit to the non-RCD side of the house consumer unit (if there is one).

 

[AndyPRK]

was it raining when you went to bed ?

It was foggy here

 

[deadshort]

Hi, i would agree it's sounds most likely to be damp getting in to something or if you have a security light on a pir on the circuit?

As has been suggested if it happens again switch off the cu in the summer house and try resetting, obviously if it trips the house cu, you may have a fault on the swa.

Regards,

DS

 

[ihawk]

So first thanks to all of the responses I really appreciate it.

Does the external part of the circuit supply anything other than the summerhouse before it gets there, outside sockets for example?

Ban all sheds, love the name, I am certainly thinking of it now I can tell you!!

The answer here is no.

Are all the summerhouse circuits on the RCD? There is no guarantee, BTW, that the RCD there would trip if there was a fault there.

Good point and yes they are.

When you had the fault did you try turning the summerhouse CU off?

No but I will if it happens again. can't believe I didn't think of that, maybe tiredness kicked in !!

What readings do you get when you do an IR test on the SWA?

honestly got know idea what that means

 

[ihawk]

Is there a junction box in the run to the summer house which has perhaps got damp?

How was the earthing connected for the summer house circuit? Did you gap it or run it all the way through? If the latter you may be able to move the circuit to the non-RCD side of the house consumer unit (if there is one).

hi mfarrow, tanks for responding. earth is connected via the main CU to a junction box then to the garage cu via the armoured cable then on from there.

 

[ihawk]

was it raining when you went to bed ?

It was foggy here

Hi AndyPRK, no rain or fog at all, but there is not external connection to bother it anyway.

 

[ihawk]

Hi, i would agree it's sounds most likely to be damp getting in to something or if you have a security light on a pir on the circuit?

As has been suggested if it happens again switch off the cu in the summer house and try resetting, obviously if it trips the house cu, you may have a fault on the swa.

Regards,

DS

Hi Deadshort no damp, or lights etc.. but I will switch off the cu to understand the fault better. Pretty certain the SWA is good. but to be honest I am assuming nothing at the moment until it's fixed

 

[ban-all-sheds]

When you installed the SWA, what did you do about testing it before putting it into service? Did you, and do you still, have the capability to do an IR test?

 

[ihawk]

When you installed the SWA, what did you do about testing it before putting it into service? Did you, and do you still, have the capability to do an IR test?

When I installed it a few years ago there was no testing as it worked a treat first go. Last night was the first problem I've ever had. No I have no idea how to do an IR test, or a test kit. Should I be looking to get someone in to do it?

 

[ban-all-sheds]

When I installed it a few years ago there was no testing as it worked a treat first go.

No I have no idea how to do an IR test, or a test kit.

Then without a shadow of a doubt you should not have done the work you did. You had (still have) no idea if it was safe, and it was also done illegally.

Should I be looking to get someone in to do it?

Yes.

 

[ihawk]

Sorry I'm a bit confused here. What your saying is all diy'er's should not do electrical installations? I came onto this forum as there are many diy'er's and many advising them how to progress certain projects.

Fair enough I did not do an IR test and still would be able to do one, but it does not mean that the installation was wrong!

When I installed the wiring here and on other projects I have done over the years I have a friend check the work (electrician). Now I've googled IR Testing I'm pretty certain he did this (I will call and ask him), at the very least he said the work was good.

I do take the point however that I'm not an electrician, but that's why I'm asking for advice here.

 

[ban-all-sheds]

Sorry I'm a bit confused here. What your saying is all diy'er's should not do electrical installations?

No, I'm not saying that.

But unlike dodgy DIY painting and decorating, DIY plumbing etc, where paint runs, crinkled wallpaper, leaky joints etc won't kill you or set fire to your house, dodgy DIY electrical work might.

DIY electrical work is fine, as long as it is done to the same sort of standards as it would be by a professional electrician. Which includes proper testing.

Fair enough I did not do an IR test and still would be able to do one, but it does not mean that the installation was wrong!

It doesn't, but lack of testing means you don't know that it wasn't.

 

[ihawk]

Fair points thanks for the feedback.