Any Ideas Why Our Box Is Tripping Out?

[UKJASE]

Need some help please guys. We are a new build house of 18 months. The last month or so, our safety cut / fuse box keeps tripping out.

We got the electrician in a week ago, and he suggested it was due to the electrics we have in the garden for our koi pond and some lighting.

I wanted to check this, as the system seems to trip out even if there has been no rain for one week. It tripped the other day, and i tried to flick the switch back up, but it tripped straight back down. I then switched all the individual switches to the off position, thinking i could put the trip switch back to on, and then open each individual switch, thus highlighting which was the problematic circuit.

I switched all to off, but still the trip switch would trip out as soon as i opened it.

I have since discovered that if i mess with the sensitivity switch a bit, and then try to open the power, the switch will usually not trip out.

The last few days it has been tripping out at 6 am, and we have not had rain for over a week.

It sometimes stops tripping out straight away, other times we will have to wait 30 minutes max.

I think there may be something wrong with the trip switch / fuse box, rather than a problem with the garden / house wiring.

Any ideas please guys?

PS i wont attempt anything myself with the box of course, it is just that the electrician who fitted it is working away at the minute, and i would like to have a better idea of where the problem lies for when he returns

[Crossy]

Look for a neutral to earth fault.

Unfortunately these can be a nightmare to find even with specialist equipment

Can you completely disconnect the outdoor stuff (both L and N) to verify if it really is the koi stuff? If it is, open up any accessible boxes and look for ants, gekkos or other assorted fauna.

[UKJASE]

Thanks Crossy. Will do as you suggested. Can you confirm though, that even if all the individual fuses are all switched to the off position, which i would presume means no electric is getting into the house, that the box could still trip out?

[Crossy]

Thanks Crossy. Will do as you suggested. Can you confirm though, that even if all the individual fuses are all switched to the off position, which i would presume means no electric is getting into the house, that the box could still trip out?

Yes, that is exactly the symptom of a N-E fault

[sanukjim]

A very bad fuze box or somehow they are others connected to your electrical line somehow..It happens often here.

[Kabula]

A real headache no doubt!!

I would hire another recommended, competent, licensed, electrician for his opinion and perhaps have him replace the fuse box to determine if it is faulty.

Is the A/C tripping it when it comes on?

Has a neighbor tapped into your electric?

Is rain water leaking in causing a short?

Is the wiring in the home substandard wire?

Perhaps one or more of the wall receptacles was wired wrong .

[Paul Laycock]

I'm not an expert, try unplugging everything and then one by one re plug your appliances in and see what happens.

Could be one idea.

[bankruatsteve]

Well, a N-E fault can be difficult but a systematic approach will usually find it. My suggestion is to:

Main breaker OFF

Using DMM on ohms, disconnect each Neutral wire at the CU (one at a time) and look for continuity (short) between the neutral wire and ground.

Test all even if continuity is found on a circuit.

For each circuit showing continuity, check all boxes in that circuit where wires are joined. Again, you are looking for gecko eggs/scat, ants, dust webs, very moist or wet condition, etc.

After cleaning all boxes, re-check continuity and most likely solved the problem. If it's a wet issue, you will need to find a prevention.

[C N K]

Hello,

If the RCBO is tripping and when you turn down the sensitivity of the RCBO the system works it means that there is bad wiring.

When you turn down the sensitivity of the RCBO your safety is gone.

An RCBO doesn't only see short cuts but also sees over wiring.

Meaning that when a neutral cable starts from a RCBO the same neutral cable needs to come back.

What happens here is that this is a lot of work to do it correctly and it's more easy to split the neutral cable in the house and connect it every where you need a neutral cable. So there is no overview anymore which neutral cable runs where and the exact same neutral doesn't come back to the RCBO.

This is an example of what could be wrong...

[bankruatsteve]

Yah whatever. In this case, the main breaker is the RCBO so it would not "know" if any borrowed neutrals. That is only a situation can occur with single circuit RCBO.

[Crossy]

@ C N K what is a "short cut" and what is "over wiring"? These are not terms I've come across in the last 40 years or so in the business.

Borrowed neutrals don't just appear overnight, our OP's system has been working for 18 months, something has changed.

His RCBO trips even if all the breakers are off, what is your assessment of this situation?

Most if not all of the adjustable RCBO's available here have a 'worst' sensitivity of 30mA which is the standard for fixed units in most of the world, how is this 'unsafe' compared with, say the UK or Australia where fixed 30mA RCD / RCBO's are the norm?

[RBOP]

I went to replace all my 20 year old breakers with ELCB breakers but 2 circuits couldnt as they kept tripping. Found that 2 lines shared a common neutral wire thus ELCB wont work.

[Dumbastheycome]

Had a similar problem which got progressively worse. Winding down the RCBO had no effect. Problem solved by replacing box. The main cut off relays were ( Or one of ) were faulty and generating heat. The cost to replace them was marginally less than an entire new board of a different brand. Never had a problem since. Some of the units may look the part but the quality does vary.

[thailand49]

One thing I know about Thailand it is it's workmanship? When many of the houses are build either the general contractor does all the work himself like water and electric or hires a separate guy for it. If the guy is any good and tells you this is the problem like you mention he should be able to correct the problem quickly. I've found lots of time worker's come in hooking up A/C, stuff don't really know what they are doing and do it incorrectly. That might be the case with you fish pond etc, it also sounds you might have a defective switch or need to up your Amps! Things are made really cheap here with no inspections that is why I keep extra parts around all the time!

[Dumbastheycome]

One thing I know about Thailand it is it's workmanship? When many of the houses are build either the general contractor does all the work himself like water and electric or hires a separate guy for it. If the guy is any good and tells you this is the problem like you mention he should be able to correct the problem quickly. I've found lots of time worker's come in hooking up A/C, stuff don't really know what they are doing and do it incorrectly. That might be the case with you fish pond etc, it also sounds you might have a defective switch or need to up your Amps! Things are made really cheap here with no inspections that is why I keep extra parts around all the time!

lol. Neighbour asked me to investigate why her washing machine did not work sometimes after she had a local "electrician" come and install some extentions to wiring.

After back tracing the installations to a central point far removed from the rudimenatry main switch I discovered that the outlet to which her washing machine was connected to was only active if the lighting curcuit also added near the machine was switched on. To comply with Thai standards I relocated the washing machine connectivity to the common inlet supply. To this day I am not sure if the washng machine was actually running through the light bulb because I altered the connections before checking that.

But the common no definition between phase and neutral connections can certainly cause some hiccups!

[BEVUP]

As mentioned the local builders wire up themselves but their are good ones & i reckon the op had a good one since he has a safety cut out box not like the sh**t i ended up with like a basic box & lights running of the outlet circuit in new Moo Baan . Developer sacked builder in the end & i can see why. Certainly not doing the tv wonders when a fluro is kicking in

[UKJASE]

Hey Guys - OP here.....

I think we have got down to why the box was tripping out. It went again a few days ago, and we called the sparky out this time. He had been once before and suggested it could have been the garden wiring. This time he had a better look, and scratched his head a lot more than the first visit. He had a bit more info from us this time, and eventually asked if we had been cut off by the electric board at all recently. We told him we had, and that they had disconnected our supply at the meter, and reconnected it once we had paid the bill.

Now the electrician knew what was wrong. The electric board had reconnected us, but had switched the two wires the wrong way round when reconnecting! It doesn't seem to have damaged anything within the house, and the board has not tripped out since saturday, so i think our sparky friend has got it!!

Happy days and congratulations to Crossey. He didnt quite predict what the electric board had done, but i think he was the closest with his neutral to earth theory

I think maybe the guys who reconnect the electric at 9 in the evening have been working a long shift

Thanks for all those who suggested solutions. Together we got there in the end

[Crossy]

Thanks for the update UKJASE. I should have thought about the polarity getting reversed.

Added to my list of thinks to check when someone has an RCD problem.

[IMA_FARANG]

Thanks Crossy. Will do as you suggested. Can you confirm though, that even if all the individual fuses are all switched to the off position, which i would presume means no electric is getting into the house, that the box could still trip out?

Yes, that is exactly the symptom of a N-E fault

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I am definitely not an electrician....but in this I will defer to your expertise.

For all it is worth, I think your probably on the right track.

Everyone seems to think a "ground" is a "ground".....but in areas that are wet in the rainy season, and dryer in the dry season.....it is simply not true that all 'earths" are "earth".