Unexplained Breaker tripping

[gdhm]

Hi,

Today an outside porch double power outlet point was not working. It worked yesterday my wife assures me and she observed nothing unusual (she had her portable stereo playing whilst working in front garden).

The double outlet on the other side of the porch was/is working fine (later found out it is on a different circuit).

I decided to check my 2 Main consumer Units box and immediately found one of the 16A breaker was off (I myself know it was on 2 days ago as I isolated an upstairs double power socket (via the Mani unit breakers) to check out where its wire went in wall (up/or) down.

I flicked the tripped breaker back on but it tripped immediately. I checked the outlet for water damage etc. but it was OK. I decided to switch the live wire leading to the (tripping) breaker with another 16A breaker's live (just in case breaker had gone faulty) expecting the other breaker to now trip AND IT DID (confirming nothing wrong with original breaker).

I went around the house checking all power outlets and lighting (including those outside house and in garden. I have checked everything (I think ) and it appears that the non-working porch power outlet is on a breaker all of its own (that's was good news ).

1) I assume that if its wiring shorted with another circuit's wiring then both circuits 2 breakers would have tripped.

PLEASE CONFIRM IF MY ASSUMPTION IS CORRECT THINKING

2a) I am assuming that this one outlet's LIVE wire SOMEHOW has become shorted with either neutral or ground (NOT AN EXPERT) and so I removed the live wire from the tripping breaker and terminated it with a high duty terminal block fitting. I did this as I assumed that now if anybody tries switching on the tripping breaker that although it will go one there will be ZERO risk as there is no live coming from it.

PLEASE CONFIRM IF MY THINKING IS CORRECT. I could have left the live connected but was worried that if (for some reason it in the future is accidentally switched on (by another) and does not trip there is a fire or safety risk as the reason for the tripping has not be found or rectified.

2b) **Please note** I did not attempt to disconnect the faulty outlet's circuits neutral wire or ground wires as it would be very hard (FOR ME) to identify for sure which ones they are. I again am assuming that with NO LIVE there is NO ISSUE if the neutral and ground wires remain connected.)

PLEASE CONFIRM IF MY THINKING IS CORRECT

3) I am somewhat concerned that this ONE outlet's circuit has shorted (or whatever) when there is no exposed wiring, nor does it ever move and not exposed to rain or water. I truthfully cannot think of ANY reason or change to cause its breaker to trip.

HOWEVER would the experts agree that I having disconnected the outlet's live from its breaker means there is NO fire or other risk form this wiring issue (whatever the reason) as the circuit is now essentially dead. (I appreciate that unless/until the reason for the fault is found and addressed that this outlet is now also dead and of no use. IS THIS A SOUND ASSUMPTION? (I have safely blocked the outlet off so nobody will try to use it (not that they would have any luck anyway( ) with no live feed.

This wire issue I feel will be very hard to locate as would installation of a new cable run to the outlet plug because the wiring is all sealed above the suspended ceiling and 2 walls in between.it and Consumer Unit.

My current thinking is that with the other porch outlet working to just leave that outlet as redundant.

My second thinking is that as the problematic outlet backs on to a room that has a power outlet about same height and only 2 metres away and I could get an electrician to connect the two and run it on the other's different circuit (PLEASE MAY I ASK - ANY REASON WHY NOT? . Neither outlet plug is barely used (one in room has never been used in 6 years of being here as it is behind a sofa (when I had house built I had double outlet placed near all 4 corners or every room and more in some (just in case future needs changed ).

=============

In summary my primary SAFETY questions are:

a) Even though I have no idea why the porch outlet wiring should have started tripping it is now not a safety issue as I have removed the Live from the breaker thus killing the wiring to the outlet (slight residual few watts as my house has a grounding rod that seems to have a 3-6 watts circulating on ground (which I am told is common on ground rod systems and unless it increases is of no concern). AM I CORRECT?

Except convenience of having the outlet working again I believe I NOW have no reason to address the reason for the tripping (curious as it is) UNLESS OTHER BREAKERS START TRIPPING). AM I CORRECT?

c) Is there any need to trace the neutral and ground wires in the consumer box from the (now extinct) outlet and disconnect them (as I have the live. I feel (rightly or wrongly) they still being connected may be beneficial or not relevant either way/ AM I CORRECT?

d) I assume had the breaker tripping on another circuits wiring that, that circuits breaker would have tripped as well.

OR, if the short (or whatever) was BEFORE the tripping breaker then the main consumer breaker and other breakers (maybe many) would have also tripped AM I CORRECT IN MY THINKING?

At end to day I would sooner leave well alone now, if safe to do so, rather than try to find a reliable electrician in Khon Kaen who actually is a "Real electrician who actually understands his trade, safety concerns and works on that basis.

So far I have found only many supposed electricians and have had to direct them myself on occasions. (how very sad that a life long clerk knows more than some of these "I have been an electrician for 20 year" types

If anybody knows of a reliable qualified (genuine expert) electrician in Khon Kaen. please, please tell me) because I desperately need one that I can rely on to know what he/she is doing and who will don it safely as it should be done without any BS.

Many thanks all for reading and for any advice on my questions.

Kind Regards

[Litlos]

First question with faulty electrics is what has changed? Have you just put any new pictures on the wall or a couple of new screws in the ceiling?

Assuming the answer to that is no or maybe then you need to isolate where the fault is, as you do not seem to averse to pulling wires out try this. Isolate the main breaker, disconnect both wires from the outlet and tape the exposed wire. Now reconnect the wire to the breaker and switch the breaker on. If it trips the fault is in the wiring (mice maybe), if no trip then the fault looks like it is in the outlet (ants maybe).

Just a thought - Do not assume the live (active) wire goes through the individual breaker, it may be the neutral and is wired backwards. Always isolate via the main breaker until it is proven that the live goes to the individual breakers. The main breaker should be two pole and so virtually idiot proof.

Cheers

[bankruatsteve]

^ Yah. It sounds like you have isolated the problem to a single outlet on a single circuit. Right? So, it seems obvious that something has happened to the outlet - like bugs or water damage causing shorting. I'm not sure why you decided to attach a "high duty terminal block fitting" as a breaker can be assumed to do what it's supposed to do.

With the breaker OFF, clean and check the connections on the outlet and re-try. If it still trips - yeah, probably mice or something shorted the cables. But, if mice can get to them, then maybe you can too?

RE "d": I thought you moved the live from the tripped breaker to another breaker and that one tripped as well. ?? If it did, then you have a short, if it didn't then ... is the breaker that tripped an RCBO? IE: does it have a test button? Which would be a different problem, like N-E fault.

BTW: I didn't go through a checklist - but most of your assumptions are correct.

[wayned]

With the breaker off, disconnect the wires from the outlet and remove it. Turn the breaker back on, if it doesn't trip, replae the outlet, there's an internal short. If it trips, you have a short in the wiring somewhere between the CU and the outlet. - have fun finding that!

[sirineou]

Word of warning , I am an armature on the subject, but this is what I would do.

It was correctly mentioned by others to isolate the outlet and see if it still trips the CB (Circuit Beaker)

if that is not the problem the next thing I would check would be the line, the way I would check that would be to connect that line to a CB of the same size that did not normally trip and see if it trips that CB , if it does then it is the line if it does not then it is possible that you have a faulty CB

once I had a CB that after years of use had become a hair trigger and it would easily trip, I simply replaced the CB and I was good to go

what ever you do, be careful, and always throw the main before you do anything and even then touch both sides of the CB with a testing device to make sure it is not live. I always wear robber gloves and I use a pigtail with a light bulb in it, to see it it lights (I told you I was an armature, there must be better testing devices but the light bulb works for me )

[NCC1701A]

yes, replacing the circuit breaker would be next before really getting into opening walls or replacing wires...

[Shurup]

Start replacing things is a Thai way of fixing the problems. Do as Wayned said, it's plain and simple, it's either line or an outlet. Remove the outlet and check if it trips again. Go from there.

[NCC1701A]

so lets think about this, you have a wire that runs from the circuit breaker box to the plug. inspect the plug and replace. cheap and easy. still tripping? inspect wire as best you can. still tripping? replace circuit breaker. CB do go bad. cheap and easy. still tripping? Replace wire. Hard and expensive.

[Shurup]

You're right, I'd replace the breaker 1st before digging out the wire, but my post was about inspecting/finding the problems 1st. There're no mysteries, if 2 CBs are tripping (he tried the line on another CB), then there's a short somewhere, find it and then see what needs to be replaced.

[bankruatsteve]

Well... IF the breaker(s) tripping is an RCBO (which would make sense if it's supplying an outside outlet) then it might just be a N-E fault and should be easy to fix by simply taking out the outlet and giving it a good vac.

[Crossy]

Indeed Steve, it's still unclear whether the device is an MCB or RCBO.

[Forkinhades]

Quickest way to find fault is to use an high reading ohm meter, disconnect cable both ends, and test. ideally you want over 200 meg ohms, but in fact anything from 500 ohm to 200 Meg ohms is good. If you have then your outlet is at fault, anything less than 200 Meg ohms will mean that your cables have deteriorated.

If you have less than 500 ohms, you can use a Low reading ohm meter, with which you can pinpoint exactly where the cable has gone 'down'.

Edited September 16, 2013 by Forkinhades

[gdhm]

Thanks for your replies Quite a lot to answer/clarify.

What has changed. Well nothing in the last few days.

About 4-6 weeks ago all the lights in the whole soi and surrounding streets soi went very bright for about up to 5 minutes before a total power failure for an hours. All our aircons were off and as it was early evening most lights too . I switched off all I could quickly and my Multimeter registered above 340V I cannot recall exact amount before I could cut the CU main breakers on seeing this the power in the local area cut out completely. Could that large voltage increase have damaged wiring in the house? This is the ONLY really unusual electrical happening.

Recently (within last 2 weeks)

1) Our mid-stair landing tube light failed after 6 years. Unfortunately it is totally out of reach for an ordinary step ladder. My wife found an electrician (who said he sometimes wire new builds for local new urb.s) He replaced the tube with a single metre long light fixture. The original idiot electrician had made a hole(looked close to 15-20 cms diameter) in the suspended ceiling and my new light's fitting was not large enough to cover it. I removed all the bits and pieces from the old tube fitment base and asked him to put that back up and the new fitting was securely attached to that. He painted the old base so it looks surprisingly quite good. 2 days after he had gone I noticed the old fitting is pulling a little from the ceiling (obviously one of the old plate screws is no longer gripping (I feel sure he must have known that when he tightened up (but good enough for him). We are currently waiting 9 days (maybe for ever) for him to come back and re-fix.

My wife noticed a day after the fitting that the 32W light ESB flickered about 20 seconds after switching off the light and continued every 10-20 seconds (VERY faint and not visible in daylight). I checked internet and found that this can happen with ESB on 2 way switches and with certain brands of ESB. The ESB bulb I was using was made in China, no brand name (had taken it from a worker's "floodlight on a tripod" I had purchased from Global. I tested with 4 other branded ESBs and NONE flickered. I put it down to tiny residual current and a poor quality unbranded bulb. I bought a 28W Toshiba and it is fine.

2). We have use an upstairs landing night-light. They seem to blow/fail every few months (on 8 hours a day in hottrest part of house) but the one in my stepson's room has lasted much longer). I tested the outlet with my multimeter but readings were normal for our house. However the failing night-lights are plugged into a double power outlet shared with a Victor cold water dispense which my wife and stepson use use a lot at night. My personal suspicion is "that the dispenser's compressor switching on/off causes power surges/spikes in the double outlet and this causes shortening of night-light longevity. Would experts here agree with my opinion? (We are now trying a Phillips 5W LED bulb now plugged via a Toshino Travel adaptor with surge protector).

3) two days ago I switched off the Consumer Unit (one of 2) and tracked down the breaker that supplied that upstairs landing outlet (and the one backing on to it from an adjoining room) and checked the wiring in both to see which way the wire travels and which side or the wall (up or down) important if I decide to add a wall fitting. I refitted both and switched on the breaker (no tripping), checked sockets with my multimeter everything normal.

These are the ONLY things touched or fitted in many months.

MY belief on whether any of these are Salient is NO (except maybe street power surge) The mid stair landing light and the upstairs landing outlets although using the same Consumer Unit (of 2) that the tripping porch outlet used are not using the same breakers and are still working perfectly.

For info: My Right Consumer Unit (existing picture before live wire disconnected from Breaker 9)

1. Litlos said ...Just a thought - Do not assume the live (active) wire goes through the individual breaker, it may be the neutral and is wired backwards. Always isolate via the main breaker until it is proven that the live goes to the individual breakers. The main breaker should be two pole and so virtually idiot proof..".

If the the Live and Neutral wires were reversed would that not mean the Live would be connected to the Common block in the CU and that would cause a massive trip/bang?

2) several posters suggested I check outlet. That was first thing I did (after I found the tripped breaker). The outlet was a little dusty but no insect or rain water damage and the wiring was sound with no exposed wires and all tightly fitted into the back of the outlet. The wiring was not near the outlet's cover retaining screws. Tripping still occurred after checking, so I removed all 3 wires from the porch outlet socket (having rechecked for Live). I tried to switch on the breaker but it still tripped almost immediately. In conclusion the Outlet socket is NOT to blame and the fault has to be in the wiring between it and the CU (even though totally unexplainable how).

3) Mice & Ants. I have no reason to believe mice or rats have got between to the downstairs ceiling and upper floor. We are plagued however with these tiny ants and they do seem to get everywhere (do they bit though electric cabling? I prey not!!). I think a bird or baby bird once (6 or so months ago) did get into the area between suspended ceiling and upper floor as I could here shuffling and chirping (only time) for one night only. I should mention, that a few areas of the cavity between downstairs ceiling and concrete upstairs floor have loft type insulation material (fibre glass with covering silver plastic foil). We had some left over having put some insulation between our front room's suspended ceiling and concrete patio floor to try and restrict transmission of heat room below (not very successful in truth). Our builder put the left overs in other random cavity areas (no real need).

4) Hi bankruatsteve (kindly advising me again ) you commented

" ..^ Yah. It sounds like you have isolated the problem to a single outlet on a single circuit. Right? So, it seems obvious that something has happened to the outlet - like bugs or water damage causing shorting. I'm not sure why you decided to attach a "high duty terminal block fitting" as a breaker can be assumed to do what it's supposed to do..".

My concern Steve was that if the fault was still there but later proved intermittent, someone in the future may see the breaker is (although I have labelled leave off) switch it on and maybe it would not trip with the issue would be dormant at best but not resolved. I felt total disconnection of the live wire made it double safe irrelevant if someone flicks the breaker back on (which of course it can be now with no live feed to trip). I am also aware that breakers although highly reliable are not static and can form time to time fail. If that one breaker failed and allowed current to flow as it would not trip we would have maybe a serious fire.

Is my THINKING WRONG on what I thought was a reasonable added safety decision bearing in mind there is no benefit having the live connected to the breaker anyway.

No it is NOT an RCBO breaker Steve (just a conventional 16A Trip breaker)

"BTW: I didn't go through a checklist - but most of your assumptions are correct." Thank goodness for that.

Shurup said "...Start replacing things is a Thai way of fixing the problems. Do as Wayned said, it's plain and simple, it's either line or an outlet. Remove the outlet and check if it trips again. Go from there..".

Shurup Oh so true!!! The ONLY query I have in my mind is "is it a Thai way" or is it a cowboys (who knows nothing or very little) way as no skills to resolve logically or in order.

I concur with Wayne and others views and as it is NOT the outlet it must be wiring. Just cannot believe or understand how the wiring has got disturbed and compromised. That is what worries me most as to whether this was a "one off" or likely to manifest itself elsewhere in future. If the issue is with another circuit in close vicinity I assume that circuit's breaker (unless faulty would have tripped as well ) IS THIS CORRECT PLEASE?

Hi NCC1701A. Not CB I feel because as already mentioned. I swapped the yellow live wire from the tripping breaker to the one next to it and that then tripped.

Hi Forkinhades I have a normal cheapish multimeter. Too be honest I do not understand Ohms and significance sorry. I personally only use the Ohms section of the multimeter to confirm continuity.

Hi again Crossy , You know my set up a little from previous posts. You and others recently gave me very good advice on RCBOs and Safe-T-Cut separate devices. My decision was made based upon your advice however not done yet (not because I am not extremely keen) but because I cannot identify an electrician I feel can trust to deal with the connections/job properly and if the Safe-T-Cuts show any issues to resolve them (I do not want an " electrician saying "I don't know the cause or how to rectify so do you want me to reconnect the original wiring". I admit I am not scared by electricity in itself. What I know I can do safely and myself I will (but what I do not know or am unsure of I will not touch myself but equally I do not want any more cowboys claiming to know what they are doing and making my electrics unsafe or less safe than before they worked on them. I have had several electrician cowboys but I'll not bore all with the sorry sometimes crazy details .

Essentially with any electrical job I am now terrified of jumping out of the frying pan into the fire. The only people I trust on electrical matters since my time in Thailand is you (100%) and various others on this site where I get real info and people willing to admit when they are unsure or not an expert. Thanks to you all.

I think the general view here is that with outlet blocked off and the live isolated from its (or any) breaker that the situation is now safe as one can reasonably tell. If such a thing happens again then I assume I should (and would need to look deeper). Would this be a fair interpretation?

Finally bankruatsteve also said "If it still trips - yeah, probably mice or something shorted the cables. But, if mice can get to them, then maybe you can too"?

This I a BIG concern of mine Steve. Just how on earth do decent electricians get to wiring above a suspended ceiling board without multiple holes needing to be made along the route OR pray that taping the 3 new wires to the old can be pulled through the plastic wall conduits/ceiling area without snaring (highly unlikely I would think). I did instruct the original electrician to run all wiring inside walls and ceilings inside plastic conduit. I know he used conduit in the walls (hopefully all walls not so sure about above ceiling). I know metal conduit is more robust and preferable but I wanted to at least have a chance of pulling/feeding wiring down walls rather than dig out wiring in walls .

I will repeat as its important (as I have jobs that can be done, checked and am bound to have more in the future)

If anybody knows of a reliable qualified (genuine expert) electrician in Khon Kaen. please, please tell me) because I desperately need one that I can rely on.

Sorry if I have missed one or two specific poster names but I think I have covered all questions and have certainly read them all.

VERY SORRY FOR LONG POST

Edited September 16, 2013 by gdhm

[bankruatsteve]

Do you write documentaries for a living? Anyway... you are very thorough. Uhm, yeah - sounds like you have a bugger in the wiring or?. Well, ceilings are not that difficult to take out a patch and then patch back up - if you want to take that route. Usually, with attic space, there are climb up holes to have access. You definitely not on RCBO, so the thoughts for that won't apply. Rambling somewhat but I don't know what I would do that except try to test the wire to make sure for the fault and just re-check everything like loose wires anywhere? Esp. in the CU. Maybe re-seat the breaker (turn main off first). In the outlet, re-check to make sure L-N-E are all in the correct holes. A short is a serious problem so I hope you can find it. Cheers.

[Forkinhades]

Hi Forkinhades I have a normal cheapish multimeter. Too be honest I do not understand Ohms and significance sorry. I personally only use the Ohms section of the multimeter to confirm continuity.

its a shame you dont understand ohms and the significance, as quite simply the test I suggested, is what I would do as a testing and inspection engineer, and the fault would be found very quickly indeed. The problem is getting a thai 'electrician' with the correct meter and correct understanding of readings.

Without said equipment and understanding you will just go around in circles trying to find the problem.

You also have the scenario of borrowed neutrals, in that you say you have isolated the live conductor, but if you have a borrowed neutral then that cable in the outlet will become live! even with the live cable disconnected!

Electricity is dangerous stuff, and really should be left to the experts.

Edited September 16, 2013 by Forkinhades

[Litlos]

Sounds like the easy options have been ruled out. The active and neutral can be swapped over in your box and not cause any major problems as there is not a connection between the neutral and earth, of course the circuit breaker being on the neutral is a problem. As you have a multimeter easy enough to verify. Set the multimeter to read about 300 AC volts or Auto range is even better. Then place one probe on the earth bar and the other on the terminal labelled "L" at the main breaker, then swap the probe to the terminal labelled "N". Ideally the reading L to E should be 220VAC and the reading N to E almost 0VAC if these are reversed then the L and N incoming wires are swapped around. What will more likely be the case is there will be some sort of other voltages, more likely in drier weather though. In the case of not exactly 0VAC on the Neutral etc the wire with the higher voltage to earth is most likely the active.

The wiring should be rated for 500VAC so the excursion up to 340VAC should not have damaged the wiring and is more likely to take out electronics and other consumer devices. However the rating on the wiring is installed correctly and not damaged. But if the insulation is damaged then maybe not so good, also this assumes the correct grade of wire has been used. If this was the problem I would have expected it to become faulty straight away, but strange things happen some times and it might have developed a bit of leakage current that got worse over time.

I have seen ants chew through PVC cable insulation in Australia and cause shorts. One job every cable we laid underground had to have a insect resistant outer nylon sheath. Stopped the ants but installing and terminating these cables was a nightmare. From memory these were Singapore ants and were small brown ones. So maybe the ants are to blame?

Anyway as you have now isolated the problem to the cable it seems that that needs replacing. If it is in conduit in hard to get at areas then it just got harder. If you can do a visual inspection of the conduit runs and notice any discoloured conduit or junction boxes then that would be a good place to start. But realistically it is not to complex as is a faulty cable and I would be all for getting the local sparkie in and watch him like a hawk. He will probably have a light weight assistant who can swing around the attic spaces like a monkey. If you check the L/N are correct on the main breaker before he gets theer then he can correct that as well as will probably involve disconnection/reconnection of live wiring, and I do not recommend you get involved in that. If the wiring is swapped and you get it sorted then put the original light that flickered back in and it probably will not flicker anymore.

Cheers

[Forkinhades]

Point to add is that I was not talking about reverse polarity. If that was the only case to consider then he would have already ISOLATED the cable regardless of colours used. Here in LOS when an extra socket is added, the 'thai' sparky will install at minimal cost, which can mean running just one cable (single core) from the DB, as the the live conductor, they will then 'borrow' a neutral from somewhere. This becomes very dangerous under fault conditions.

All you really need to do is an Insulation Resistance test, which can be done quite easily in isolated conditions. You only need to measure voltages after isolation to prove said circuit is dead. ie by testing all cores.

[Forkinhades]

Just seen the picture posted earlier by gdhm.

Thais do not as rule install ring circuits. You have 2 MCB's with 2 cables in, and quite a few screw joins inside the DB. Your neutral block is full, and does not seen to have the same amount of neutrals as live cables, which suggests borrowed neutrals have been used.

I counted 21 live cables. So you should have 21 neutral cables in that neutral block. If not then you have borrowed neutrals.

Edited September 17, 2013 by Forkinhades

[gdhm]

Do you write documentaries for a living? Anyway... you are very thorough. Uhm, yeah - sounds like you have a bugger in the wiring or?. Well, ceilings are not that difficult to take out a patch and then patch back up - if you want to take that route. Usually, with attic space, there are climb up holes to have access. You definitely not on RCBO, so the thoughts for that won't apply. Rambling somewhat but I don't know what I would do that except try to test the wire to make sure for the fault and just re-check everything like loose wires anywhere? Esp. in the CU. Maybe re-seat the breaker (turn main off first). In the outlet, re-check to make sure L-N-E are all in the correct holes. A short is a serious problem so I hope you can find it. Cheers.

You should have seen my first effort (well just as well you didn't. Part of reason is I try to answer each who have offered advice/made queries, another part is not being an electrician I do not always know what is salient, main reason long winded , repetitive and sometimes cannot see "wood form trees. I am very sorry all.

I will be shorter. Whilst my mind was churning over problem (really worrying me as I do not like unexplained mysteries (maybe safety issues) with water or electricity I suddenly remembered an outlet I have not tested (unfortunately it proved not to be the issue). It's our only outlet on our perimeter walls (front) and is used to supply our small ponds water fall (damn!). when I tested it (after touching a huge spider -all spiders scare me- inside the weather proof box) I found it to be dead so I knew it shared the same circuit and it is in a logical direct line to the porch outlet and CU meter. Cutting to chase, there was evidence water had got in at sometime BUT the outlet socket itself is NOT the cause and no water present today. I disconnected the wires form the socket completely and the trip still occurs however this time it took 5 seconds to trip but second and third attempts tripped instantaneously (no idea why 1st took 5 seconds). The wire is different as there is a 4th unused wire, red blue black and grey (blue not used). This cable travels under our lawn (about 8 meters, another 15 meters under tiled walkway around house. I am thinking water under the lawn or somewhere along its part of the circuit has been water compromised which would seem more likely I feel than rodents. I wonder if my original "wonder" electician made a join underground!.

This socket not working is a real nuisance there is an outside outlet on our house wall but the electrician would have to somes how go under 1 meter or walkway to get it to house wall.

Thanks on how to check L & N in CU Litlos, I did as you suggested and Neutral to Ground (4W) and Live to Ground (258W) 12 noon (quiet time of day) to main Breaker in CU are wired correctly. I noticed yesterday night the Live to Neutral was 246W. weeks ago when I last tested it was around 231W best time of day and 216W early evening

Are high reading like this OK for appliances or do they suggest PEA electricity to our soi has a problem?. IF OK how high is OK before I should worry?

its a shame you dont understand ohms and the significance, as quite simply the test I suggested, is what I would do as a testing and inspection engineer, and the fault would be found very quickly indeed. The problem is getting a thai 'electrician' with the correct meter and correct understanding of readings.

Without said equipment and understanding you will just go around in circles trying to find the problem.

You also have the scenario of borrowed neutrals, in that you say you have isolated the live conductor, but if you have a borrowed neutral then that cable in the outlet will become live! even with the live cable disconnected!

Electricity is dangerous stuff, and really should be left to the experts.

I 100% agree with your last sentence but I have no idea how to find a genuinely qualified knowledgeable electrician in Khon Kaen. Of course there are some (probably many) but I speak no Thai to do my own research and my wife (like many Thais tends to trust everybody's recommendations as factual and accurate (hence why to date we had had "jack of all trades (dangerous with electricity). The origianl house builders electrician was given very cleaqr instructions the biggets being I want EVERYTHING to have a Ground wire (even if not used INCLUDING LIGHTS fittings. He ignored grounds for the Lights I found out very late in the day and had he said intially what he said to my wife I'd have demanded a different electrician. He told me wife "No problem in Thailand we do not need ground wires for light fittings as they do not need them" I was NOT happy and asked him why the down-light fittings I had selected had a gorund terminal IF in Thailand lights do nto need them" He thern tricked me by saying he'd rectify but certainly with one light fitting all he did was connect a ground wire to a ground terminal and push the other end into the ceiling cavity. People who are willing to make a false ground are "criminal" in my view and much worse than those who do not add a Ground coz with those you know there is not one.

I believe the electrician did "overall did do a good job and did know more than others I have celled on BUT clearly hew has a very poor sloppy attitude on safety (and needs to be watched by an expert)

It seems nobody who has followed this post comes form Khon Kaen or if they do knows a good electrician).

If anybody has pointers where I might best search for one and how to know a cowboy from the real article please tell me as I want to check this out, I want to get both outlets safetly operational again and I really want to .fit 2 safe-t-cut type devices one for each CU and ifd they trip when they should not an electrician capable of finding source and rectifying (I appreciate cutting strategic holes in my downstairs suspended ceiling will be necessary but I do not want some idiot turning it into a mini golf course due to ignorant guess work.

[Litlos]

Point to add is that I was not talking about reverse polarity. If that was the only case to consider then he would have already ISOLATED the cable regardless of colours used. Here in LOS when an extra socket is added, the 'thai' sparky will install at minimal cost, which can mean running just one cable (single core) from the DB, as the the live conductor, they will then 'borrow' a neutral from somewhere. This becomes very dangerous under fault conditions.

All you really need to do is an Insulation Resistance test, which can be done quite easily in isolated conditions. You only need to measure voltages after isolation to prove said circuit is dead. ie by testing all cores.

I was answering the OP, not you. The point was do not trust the single breaker isolation unless you are 100% sure that it is switching the active.

The wiring is a bit funky in this box, but it looks like about the correct number of neutrals as they are doubled up, hard to 100% confirm as the incomer cables are in the way. It appears the original sparky is not very good at allowing enough spare wire to terminate and has added on extra using wirenuts to join. Not brilliant, but better than the usual Thai twist and tape method of joining wires.

I enlarged the photo to see if they were adding in any extra wiring via the wirenuts, it does not appear so, but the wiring going through the punchouts in the box is interesting. The punchout edges are not protected and there is bare metal rubbing on the wiring, would have also been scraping the wiring as it was brought into the box. Is there a sizzle and pop close by when bringing in the breaker?

Cheers

[gdhm]

bankruatsteve said:

Do you write documentaries for a living? Anyway... you are very thorough. Uhm, yeah - sounds like you have a bugger in the wiring or?. Well, ceilings are not that difficult to take out a patch and then patch back up - if you want to take that route. Usually, with attic space, there are climb up holes to have access. You definitely not on RCBO, so the thoughts for that won't apply. Rambling somewhat but I don't know what I would do that except try to test the wire to make sure for the fault and just re-check everything like loose wires anywhere? Esp. in the CU. Maybe re-seat the breaker (turn main off first). In the outlet, re-check to make sure L-N-E are all in the correct holes. A short is a serious problem so I hope you can find it. Cheers.

You should have seen my first effort (well just as well you didn't. Part of reason is I try to answer each who have offered advice/made queries, another part is not being an electrician I do not always know what is salient, main reason long winded , repetitive and sometimes cannot see "wood form trees. I am very sorry all.

I will be shorter. Whilst my mind was churning over problem (really worrying me as I do not like unexplained mysteries (maybe safety issues) with water or electricity I suddenly remembered an outlet I have not tested (unfortunately it proved not to be the issue). It's our only outlet on our perimeter walls (front) and is used to supply our small ponds water fall (damn!). when I tested it (after touching a huge spider -all spiders scare me- inside the weather proof box) I found it to be dead so I knew it shared the same circuit and it is in a logical direct line to the porch outlet and CU meter. Cutting to chase, there was evidence water had got in at sometime BUT the outlet socket itself is NOT the cause and no water present today. I disconnected the wires form the socket completely and the trip still occurs however this time it took 5 seconds to trip but second and third attempts tripped instantaneously (no idea why 1st took 5 seconds). The cable to the waterfall's outlet is different form the porches (thick outer sheaf but there are 4 wires, red (Ground), Black Live), grey (neutral) & blue unused). This cable travels 8 metres under our lawn & another another 1.8 meters under our tiled walkway around house. I am now thinking water under the lawn or somewhere along its part of the circuit has been water compromised (rather than wiring between porch outlet and CU) which would seem more likely (to me) than rodents in the ground floor ceiling I wonder if my original "wonderful " electrician made am insulation tape join underground(i know he placed garden wiring in yellow plastic conduit (as instructed me me).

This water fall outlet socket not working is a real nuisance. There is another outside double outlet on our side of house but the electrician would still have to go under 1 meter of walkway to get it to house's wall.

Litlos Thanks on how to check L & N in CU. I did as you suggested and Neutral to Ground (4W) and Live to Ground (258W) 12 noon (quiet time of day) to main Breaker in CU are wired correctly. I noticed yesterday night the Live to Neutral was 246W. weeks ago when I last tested it was around 231W best time of day and 216W early evening

Are high reading like this OK for appliances or do they suggest PEA electricity to our soi has a problem?. IF OK how high is OK before I should worry?

Forkinhades said:

its a shame you dont understand ohms and the significance, as quite simply the test I suggested, is what I would do as a testing and inspection engineer, and the fault would be found very quickly indeed. The problem is getting a thai 'electrician' with the correct meter and correct understanding of readings.

Without said equipment and understanding you will just go around in circles trying to find the problem.

You also have the scenario of borrowed neutrals, in that you say you have isolated the live conductor, but if you have a borrowed neutral then that cable in the outlet will become live! even with the live cable disconnected!

Electricity is dangerous stuff, and really should be left to the experts.

I agree but I am a retired clerk with a little electrical knowledge picked up on the way and one this forum.

I agree 100% with your last sentence BUT I have no idea how to find a genuinely qualified knowledgeable electrician in Khon Kaen. Of course there are some (probably many) but I speak no Thai to do my own research and my wife (like many Thais) tends to trust everybody's recommendations as factual and accurate, hence why to date we had had "jack of all trades' or worse (dangerous with electricity). The original house builder's electrician was given very clear instructions, the biggest being I want EVERYTHING to have a Ground wire (INCLUDING LIGHT fittings). He ignored grounds for the Lights but I found out very late in the day. When I found out and demanded he rectify he told my wife "No problem in Thailand we do not need ground wires for light fittings as they do not need them" I was NOT happy and asked him why the down-light fittings I had personally purchased selected had a ground terminal on them IF in Thailand lights do not need them" He made a sheepish grin and said he'd rectify He did some (or the one that he offered me to test which I did) but with some (no doubt difficult to access) he tricked me as all he did was connect a ground wire to the electronic starter ground terminal on a ring tube fitment and pushed the other end (10 0r so cms) into the ceiling cavity area. People who are willing to make a false ground are "criminal" in my view and much worse than those who openly do not add a Ground coz with those you know there is not one.

I believe the electrician did "overall a good job and did know more than others I have used BUT (a BIG BUT) he clearly has a very poor sloppy cavalier attitude on safety when it suits (and needs to be watched by an expert)

===

It seems nobody who has followed this post comes from Khon Kaen or if they do knows a good electrician).

If anybody has good pointers where I might best search for one and how to know a cowboy from the real article please tell me as I want to check this out, I also want to get both outlets safely operational again even if on different/new circuits and I really want to fit 2 safe-t-cut type devices (one for each CU to cope with ampage and not all eggs in one basket (so to speak) and should they trip (when they should not) an electrician capable of knowing how to find source and knowing how best and safely to rectify (I appreciate cutting strategic holes in my downstairs suspended ceiling will be necessary but I do not want some idiot turning it into a mini golf course due to ignorant guess work.

Thanks for any further advice on safety (if needed) or seeking an electrician. I really appreciate all you guys for your knowledge, advice kindness, concern and time on not only this Post but others in the past as well Kop Khun Khrap

[Shurup]

The unprotected edges in the box could be an issue, however there is no vibration at the box and wires aren't moving in/out all the time so this shouldn't be a problem now if there was no problem before.

OP said the cable runs under ground and under the walkway??? Can you post a pic? If you have cement slabs over gravel kind of walkway, the gravel or rocks could have damaged the cable insulation as the traffic on the walk way moving back and forth. That if the cable isn't protected somehow.

[gdhm]

I enlarged the photo to see if they were adding in any extra wiring via the wirenuts, it does not appear so, but the wiring going through the punchouts in the box is interesting. The punchout edges are not protected and there is bare metal rubbing on the wiring, would have also been scraping the wiring as it was brought into the box. Is there a sizzle and pop close by when bringing in the breaker?

Cheers

Yes I noticed no rubber grommets protecting the cabling where any enter BOTH CU cases. Very poor (and stupid imo) but thankfully things do not move but clearly a potential weakness if any OF THE wires are being heavily pushed against any of the hole edges.

No sizzle or pop that I noticed Litlos. I will see if I can see any wires being pushed on hole edges and slacken (if I can get to them - very tight access around some holes or many wires in the way). If I can I will try to push a plastic/polythene sheaf between some hole edges and wiring but some in both CUs seem totally inaccessible to do that.

If I can find an electrician maybe I can ask him to deal with it and make safer.

Edited September 17, 2013 by gdhm

[Litlos]

Ok so the active/neutral is good assuming you meant V not W. The Neutral to earth now just indicates how good the earth stake is at the transformer and 4V is not to bad. The nominal voltage L to N in Thailand is 220Vac, so as a rough guide it should be this plus minus about 10%, so anything between 200V and 240V is good. If you are getting 260V then this is getting to high. Sometimes if there is heavy electricity users nearby (factories) they bump up the volts on the mains and all is good while the load is high, when the load drops the volts shoot up. The same can be true if only domestic and the load comes on at late afternoon/night when people are cooking and using air conditioners.

It is getting interesting with the extra leg on the circuit going to the water feature. This leg going underground and changing cable type seems to draw suspicion that it is the culprit somehow. Would be interesting to know where and how the joint is made.

Is easy enough to run a new cable under a 1 metre path without disturbing it, I have gone under a 3 metre driveway in Aust using a piece of conduit as a tool, a trick I learned from people who run in gas lines, if you need to know I would have to do some sketches otherwise would be war and peace in words. However if you get a sparklie in then he should know how to do it.

Just a thought why not put a request in the Isaan forum referencing back to this one, you may get someone who follows the Isaan forum but not his one?

Cheers

[gdhm]

The unprotected edges in the box could be an issue, however there is no vibration at the box and wires aren't moving in/out all the time so this shouldn't be a problem now if there was no problem before.

OP said the cable runs under ground and under the walkway??? Can you post a pic? If you have cement slabs over gravel kind of walkway, the gravel or rocks could have damaged the cable insulation as the traffic on the walk way moving back and forth. That if the cable isn't protected somehow.

Your wish is my command

A B C D

[Litlos]

As they say a picture is worth a 1000 words. If it was me I would carefully dig out the soil and follow where the cable/conduit goes that supplies the outlet for the water feature. Based on it being relocated late in the build and the wires changing colours you have all the ingredients for a sloppy job where an extra piece of whatever cable was just joined on the end of the existing to give the extra length, and there is probably a twist and tape joint there somewhere. In the photo showing the original cable the cable does not look to be to big either, then it looks like a different sort of conduit was used, maybe water pipe. It may not have even been the sparkie who did this, may well have been the odd jobs man.

Cheers

[bankruatsteve]

So, the outlet in the porch is connected to wire that goes out to your waterfall - is that right? And that's the circuit with the breaker tripping, yah?

Disconnect all wires (can leave ground connected) in the porch outlet and leave them separated. See if the breaker turns on. If it still trips, the problem will be in the wire from your breaker to the outlet (assuming that's the first place it stops). If it doesn't trip, the problem most likely a short underground somewhere (which you can easily test with ohmmeter).

Make sure no kids around when you leave wires dangling out of the box and if the breaker does not trip then turn it off before doing anything else.

Edited September 17, 2013 by bankruatsteve

[gdhm]

It was the "sparkie" who relocated the cable and it is now thick and black outer sheathing. I have just looked again (whilst terminating all the wires in the box and whilst pulling slightly at the wire I found that the blue conduit moved up a little with it. Obviously the vertical section is not secured to the horizontal (and is now blue whilst original was yellow). I am wondering if the sparkie has merely gone below ground level on the original cable and redirected it to left of pond. IF thta is indeed what he has done then he must have made a join as the original cable looks whitish and thinner (as you noticed) AND although I cannot see how long the original cable is it does not seem long enough reach the new location without an extension. Of course (and I do not know) the sparkie may have rewired to the new location BUT if he did then I feel he would have had to make a join because our decision for a pond was not early in the build and the walkway at front of the house porch I feel was almost certainly in place already (remembering nearly 6 years back is hard).

Either way things do seem to be pointing to the part of the circuit between front wall and walkway. I will probably wait until monsoon ends and ground although still quite soft is not wet and sticky similar to clay. I know behind the pond and below its site we chucked many rocks to try and create a firmer more level base below the pond. even so it has tipped a little towards side wall. If cable is below pond and rocks that may have pieced, crushed cable. My hunch is on a join.

The garden get very mushy and soft during monsoon firstly it slopes back to front and secondly I know the water table is only a metre or two down because the builder left putting the septic tank into the back garden to late monsoon. He had a nightmare because it floated and eh and the workers could not bail out the water without it refilling

The builder was my wife's uncle a family builder for 40 years but I think he methods were also 40 years old and Thai Mai Pen Rai standards. He asked me to write out a contract for the build and I did one (I knew legally I could never uses it with a family member). I found it today and my condition 6 (although I am sure not adequate for electricians like Crossy, Steve and others shows how important I (a clerk) considered the subject and I tried to steer what I felt was important basics (some based on advice from Crossy long ago (e.g. wire gauges)

These were conditions 5 & 6. Of course water off a ducks back and not passed on in entirety despite constant reminders. I got so fed up being ignored (and to be honest my wife saying don't worry he (her Uncle) knows what he is doing) I stopped going to the site to avoid arguments.and frustrations of being nodded to and then them doing their own way after I left. This resulted unfortunately in the electrician not being monitored and as my wife's Uncle ran into financial issues he started (unknown to me) telling plumber and others how to do their jobs (to save money) and he was absent (instead of overseeing) trying to find cheaper sources of material.

Edited September 17, 2013 by gdhm

[gdhm]

So, the outlet in the porch is connected to wire that goes out to your waterfall - is that right? And that's the circuit with the breaker tripping, yah?

A: Yes seems so. I cannot be 100% sure BUT certainly BOTH outlets are now dead and not working (but were before), and they are in a fairly logical line between waterfall outlet, porch outlet and the CU. No other Breaker in either CU has tripped so the waterfall outlet should be live IF not on same circuit.

Disconnect all wires (can leave ground connected) in the porch outlet and leave them separated. See if the breaker turns on.

If it still trips, the problem will be in the wire from your breaker to the outlet (assuming that's the first place it stops). If it doesn't trip, the problem most likely a short underground somewhere (which you can easily test with ohmmeter).

A: If I understand what you are trying to check then I am afraid that will not work Steve. Unfortunately whilst the 2 outlets share the same circuit, the waterfall outlet wiring does not join up directly inside the Porch outlet box. I think they must meet somewhere in the porch or main room ceiling cavity (as conduit to porch outlet back box goes UP. I therefore cannot separate them and would have made your test earlier in the hope of getting maybe the porch outlet back on line if issue with the cabling to the waterfall outlet .

Make sure no kids around when you leave wires dangling out of the box and if the breaker does not trip then turn it off before doing anything else.

A: I need to be very careful on that front Steve because my stepson is ADHD and is scatty and cannot be relied upon to either listen or remember (even though now 10). ADHD children just think differently (in varying degrees) at times.

My stepson will, for example, associates switching on upstairs lights with night & darkness and not with being able to see. Consequently: Middle of the day, broad bright daylight if he he goes upstairs: mid landing, upper landing, his bedroom and upper bathroom lights all ON (he forgets the nightlight (phew! ). I have told/begged him a million times and explained. I get a genuine "Sorry Daddy" every time, but next day....... well you get the picture. My hair would be grey if I was not already almost bald .

Thanks for you suggestions Steve

[gdhm]

*** UPDATE *** ISSUE FOUND PORCH OUTLET WORKING & Front Wall (waterfall) outlet (sacrificed currently).

A NEW was found Problem today namely water seeping from Upper Patio (facing house its left floor joins above right wall of Porch (same wall Faulty outlet circuit that tripped Circuit Breaker).

My wife noticed water coming out of the Porch central tube light and between it and the porch right wall were 2 very wet patches in the porch suspended plasterboard ceiling.

I removed part of the most damaged part of ceiling AND as in same area (although dry) the part of ceiling above the porch outlet thta stopped working due its Breaker tripping (what this OP was about).

I found a very messily wired overfull (IMHO) Junction box (picture and notes below)

I separated the front wall (waterfall) outlet wiring from the porch outlet (leaving ONLY the porch outlet in the circuit to the CU. NOW the porch outlet works perfectly and the Breaker does not trip. Whilst I am unhappy about the water damaged porch ceiling and cause (probably a gap between upper patio floor and wall cement, tiling sealer - more bad building) it did give me a good chance to locate the junction box look at the wiring and get at least the porch outlet back on line. Clearly the wiring between the Junction box and front wall outlet is compromised somewhere (I suspect a cable wire join may have been made under ground close the front wall outlet (will dig and take a look when monsoon season ends)

I believe the water porch ceiling damage is caused by pools of water that sometimes accumulate in the front left corner area of the upper (exposed to the sky) patio when the left (of 2) patio drain hole blocks with debris and algae and a pool develops. We seldom use, check/clean the upper patio and do not notice very quickly when the drain hole blocks and a largish pool can form 1 mtres (front) x 2 metres (side wall that is above porches right wall (facing house0) . Birds building nests have a lot to do with the dropping of debris that blocks the drain hole, sunlight and thick slimy algae are the other cause when a pool develops.

I attach 3 photos with notes because those who have helped me with this post deserve to know my findings AND as they say "A picture is worth a thousand words" (2000-3000 in my case ).

I am sure the electricians amongst the readers of this post will NOT be impressed with the house builder's electrician. I am unhappy that internal house lights in the main lounge are on the same circuit as outside lights where some travel under the garden and NONE appear to be grounded as specfied by me in building contract. I feel outside lights should have been on a different circuit and certainly the front gates and garden lamp posts (most likely to get water in the wiring and will take out a lot of other lights and half the main lounge lights).

When porch ceiling is fixed (although not pretty) I will leave a small access hatch below the junction box (in case future issues arise)

Photos explain most queires I think (did my best guys)

Any recommendations on best way to seal a patio floor/wall joint will be much appreciated. I will not do job myself, but currently,I am thinking of a sloping line of cement about 2cms up the side wall sloping down/out on to the Patio floor tiles by 2cms from wall.

Regards

Edited September 21, 2013 by gdhm