I Think Rewiring Needed But Not Sure Exactly What

[bankruatsteve]

15 minutes ago, maxpower said:

The OP has no electrical experience and you are bombarding him with ideas and suggestions that could lead to disaster.

 

@Dene16 Has told you that no experienced electrician would suggest increasing breaker size to avoid nuisance tripping and he is absolutely correct. There could be hidden joints that continue with cables below required capacity. Its a NO NO suggestion for the inexperienced, period.

This whole story has one huge red flag and any experienced electrician would jump on it immediately.

 

When the distribution board isolator is in the off position,  the shower continues to work !

 

There is now only one road forward and it don't include running off to DIY stores to buy magic breakers. The installation has serious problems and requires proper attention ASAP.  Preferably not by the idiot who connected the shower directly to the street.

 

Thankfully the OP has started to get a grip on the situation and realized he needs to make drastic changes to the distribution arrangement. This of course is where a few pointers will help him  deal with a Thai electrician.

The only bombardment with this is your useless drip.  The wires currently on the C10 breaker are rated for 20 amp.  The shower doesn't go through the CU which is why the recommendation to add the RCBO.  The OP has the advice he asked for and can make decisions from that.  You setting off delusional alarms at this point doesn't help anybody.

[Crossy]

@maxpower you are of course 100% correct, however we 'aint in Kansas (or wherever) and decent or even half competent electricians simply don't exist (at domestic level) in significant numbers in sunny Thailand.

 

Of course if you could point him at one he would be eternally grateful.

 

Wiring the shower (or aircon or whatever) directly to the incomer is worryingly common here, replacing the stand alone MCB with an RCBO gets it safe(er) still rough but safe.

 

Our aim is to get our OP safe quickly at reasonable cost without necessarily ripping out the entire system, if he's renting he doesn't want to spend pots. Any and all assistance beyond "employ a competent electrician" is more than welcome.

 

That's why we are here, I truly wish this forum wasn't necessary, but such is life in Thailand.

 

 

[maxpower]

19 minutes ago, bankruatsteve said:

The only bombardment with this is your useless drip.  The wires currently on the C10 breaker are rated for 20 amp.  The shower doesn't go through the CU which is why the recommendation to add the RCBO.  The OP has the advice he asked for and can make decisions from that.  You setting off delusional alarms at this point doesn't help anybody.

[Elkski]

My suggestion was to add 2 circuits and only 10 amp ones so that the smaller gauge wiring is ok.   I assume the existing wires are modern and in ok condition.  No reason to yank that out.   I did suggest possibly running a single ground wire if desired.  I have read lots in a Thailand home building thread and it sounds like the only homes with a ground are farang built ones.   

[bankruatsteve]

25 minutes ago, Elkski said:

My suggestion was to add 2 circuits and only 10 amp ones so that the smaller gauge wiring is ok.   I assume the existing wires are modern and in ok condition.  No reason to yank that out.   I did suggest possibly running a single ground wire if desired.  I have read lots in a Thailand home building thread and it sounds like the only homes with a ground are farang built ones. 

The OP's house was not designed for electric by a professional.  We are dealing with what he's got.  Yes, it would be best to re-do, but not necessary for just making things work.

 

Edit:  Almost all new build homes in Thailand will have ground.  Thai/Farang/whatever.

[grs90]

Ok, thanks guys, I am overwhelmed (in a good way) by all the advice being offered. Based on what I have learnt from all the very helpful posts in response to my plea for help I think I may have been a little bit over excited regarding the need to replace all the wiring and run earthing cables everywhere. If I have understood things correctly whilst this would add some comfort for me it isn't strictly necessary where there are correctly sized, good condition, untampered with cables already in place and where the outlets served by those cables are not going to be used for equipment which actually requires grounding. Although ripping out everything and starting over would happen in an ideal world I can get to an acceptable standard, safety wise, with a less comprehensive solution.

 

On that basis I could save some time, money and effort by only looking to replace/enhance the wiring where it has been cut in to or where it needs additional earthing.

 

I've therefore scaled back a bit on what I plan to do. Scope of work will therefore be as follows, with all the actual installation work and connections to be done by the best local electrician I can find and my role limited to watching him to make sure he does what I want.

 

First job will be to fit a new consumer unit - Like this one C-UNIT + SAFE-T-CUT RCBO 6P 50A. SAF SKU ID: 255146 from Homepro.  https://www.homepro.co.th/product/255146

 

I'll get a new unit fitted to replace the existing box and make sure all the circuits are put in to it including the shower. As well as getting the box installed I think I need to get it grounded. Is that correct and, if so, what mm size cable needs to be used from the box to the rod?

 

With that in place, when it comes to earthing the existing outlets it seems the advice is that it is only really necessary to do this for the outlets in the kitchen and where the computer is used rather than running earth wires everywhere. If that is correct then presumably I need to get earth wires fitted to those sockets and connected up either to the earth rod serving the new consumer unit or new independent earth rods. Or, presumably these earth cables could instead be connected in to the earth bar in the new consumer unit if that is easier. Again, is that correct please and what size cable should be used for this?

 

Based on the advice here and on what I have read elsewhere I think two circuits for the outlets should be sufficient for the house. That should let me put the originally installed sockets on to one circuit and all the ones added over the years, which are mostly in the kitchen, on to the other.

 

Where the original wiring was cut in to to provide additional sockets & lights I will get those connections taken out and put things back as they originally were. Those cables seemed to be in good condition except for where they had been butchered with a knife so I will just get those bits attended to. I can then get the electrician to concentrate on checking/replacing the new wiring and sockets and creating a new circuit up to the consumer unit for those.

 

I'll also get him to put all the lights, original and new, on to a single circuit separate to the sockets with its own connection in to the consumer unit. So this will (should) end up with 2 circuits, each with one aircon; 2 circuits for the sockets; 1 for the lights and 1 for the water heater. Regarding the breakers in the consumer unit I was thinking to leave the aircons on 20 amp ones as that is what the guy who installed them used; put the sockets on 16amp ones and the lights on 10amps. What rating breaker should the shower (3.5kw) be on please and do I need to get the existing circuit breaker for it removed or can I just leave it alone?

 

Then, with the above all complete, I should have a house that is generally safe, certainly better than now, and whilst it may not be fully up to western standards it probably won't kill me or the family any quicker than driving on the roads here is likely to. Let me know please if that is not the case.

 

Cheers

[bankruatsteve]

One "problem" with Safe-T-Cut boxes is that they are pre-loaded with breakers of various size (in amp) and are not exchangeable.  Make sure the breakers for the box you have scoped out will fit to your plan.  Otherwise, you can go with a DIN mount box and put in breakers as you choose.  

 

[Crossy]

+1 ^^^

 

Personally, I would go DIN anyway, probably slightly more expensive, but infinitely customisable.

 

[Led Lolly Yellow Lolly]

On 24/08/2017 at 8:30 AM, Crossy said:

+1 ^^^

 

Personally, I would go DIN anyway, probably slightly more expensive, but infinitely customisable.

 

MegaHome recently opened a branch a short distance from me and I was delighted to find they stock Siemens RCBOs. I'm a bit perplexed at the reversal of Live and Neutral on them, I guess this is the versatility of the DIN system though, the incomer and mini breakers would just be arranged from right to left instead of left to right. I'm presently constructing another 18 buildings that I'll be wiring myself later in the year. I'd previously been using the Schneider plug in system on earlier builds but I've been unhappy with the reliability of Schneider RCBOs.

 

My family and I just moved into a new house, which I wired in a hurry to get it operational. I used ABB RCD with a separate overcurrent protector. This is wired in TT configuration. I know I get zero out of ten for neatness, but as I said I did this in a real hurry and with cable scraps. I'm still pulled between ABB and Siemens for the new builds, maybe you have some experience with reliability and can comment. I'm leaning towards Siemens. . .

 

 

 

On 22/08/2017 at 7:58 PM, bankruatsteve said:

Edit:  Almost all new build homes in Thailand will have ground.  Thai/Farang/whatever.

 

The problem with this is the people installing the rods just don't understand what they're doing, farang or otherwise. In 16 years here I've never seen a good job done of grounding, be it badly sized ground conductors, lack of corrosion protection, ground rods that are too short, multiple ground rods used in a way that could cause dangerous touch voltages between grounded surfaces, ground rods buried in concrete so inspection is impossible etc etc, the list could go on forever. If you can't see it and inspect it, it should be assumed it's non-functional or non-existent.

 

 

On 22/08/2017 at 4:35 PM, Crossy said:

Our aim is to get our OP safe quickly at reasonable cost without necessarily ripping out the entire system, if he's renting he doesn't want to spend pots. Any and all assistance beyond "employ a competent electrician" is more than welcome.

 

I've seen some truly horrific wiring jobs here. The house we just moved out of originally had an electric shower wired DIRECTLY to the three phase cables on the PEA side, by means of a splice with insulation tape (no breaker of any kind, no means of isolation). Frightening. I don't need to explain this to you of course, you know the deal, but like you I'm quite sincere that I want to help people get their house electrically safe. I mulled the idea of suggesting a list of local 'experts' that forum members could call upon to go take a gander at their electrical system for the price of a chin wag and a beer. The problem is I personally am not really interested in getting involved face to face with other forum members. Every time I see a topic like this though, I just want to go and scream, "This is what you need to do!" 

[oldwelshman]

I recently overhauled my inlaws which was a death trap. Had to go to "in sealed, open terminal" meter on lamppost, insulated gloves and tools to remove supply, then fitted a new split fuseboard with 2 rcd's.

I disconnected all cables as they were "twisted and non insulated" and I put two ligh circuits on 2 10a mcb, then two separate ring mains on two 30a mcb, separate supply for "hut" in trunking at 3m high and also fitted a separate main rcd to supply board so no need in future to hack the street meter!!

In short, you have no idea what is connected where so go to megahome abd buy a new board and pay a qualified person to connect circuits so they will o be overloaded.

Your board only has 4 way!

People forget it is easy  overload a socket circuit with too many appliances plugged in, TV's computers, table lights, then someone decides to put a toaster on then wife dries hair lol result, overload.

I always put kitchen on its own supply, upstairs sockets separate to downstairs, aircon on another, outside lights on another etc.

There is nothing to be saved on not having extra protected circuits.

Of course this assumes 100a Cable feed to house lol

[Crossy]

10 hours ago, oldwelshman said:

then two separate ring mains on two 30a mcb

Did you fit BS1363 outlets and plugs too?

 

If you did not, please replace those 30A breakers with 20A units. A non-fused Thai 16A plug on a 30A breaker is a recipe for a fire.

 

Ring finals are a peculiarly British thing, don't wire them anywhere outside the UK (even places like Singapore, HK and Malaysia which use BS1363 plugs use radial finals).

[KittenKong]

On 21/08/2017 at 6:42 PM, bankruatsteve said:

How do you define a "REAL" electrician in Thailand?

 

The real ones are still alive.

[oldwelshman]

6 hours ago, Crossy said:

Did you fit BS1363 outlets and plugs too?

 

If you did not, please replace those 30A breakers with 20A units. A non-fused Thai 16A plug on a 30A breaker is a recipe for a fire.

 

Ring finals are a peculiarly British thing, don't wire them anywhere outside the UK (even places like Singapore, HK and Malaysia which use BS1363 plugs use radial finals).

Actually they were 20a mcb's, had my UK head on yesterday lol Bought the unit from megahome. When I build house next year will ensure wiring uk style ;-)

[Crossy]

11 minutes ago, oldwelshman said:

When I build house next year will ensure wiring uk style

Don't use ring finals, make them radials in 2.5mm² on 20A breakers, have two radials running to the kitchen.

 

Ensure you implement MEN in the approved Thai manner (have a look in the pinned threads).

 

Do everything else á-la UK and you'll be fine.

 

EDIT If you want to wire to a standard that's in English then AS3000 is the nearest fit to the Thai wiring requirements.

[sometimewoodworker]

On 29/08/2017 at 3:15 PM, oldwelshman said:

Actually they were 20a mcb's, had my UK head on yesterday lol Bought the unit from megahome. When I build house next year will ensure wiring uk style ;-)

FWIW ring finals are deprecated for new installations in the U.K. one reason being the more difficult testing needed, another is the more complex failure modes leaving the circuits unexpectedly live, together with the fact that they have virtually no benefits compared to radial finals. That doesn't include the fact that almost nobody outside the U.K. can understand them and (like the Spanish Inquisition) nobody expects to find them

[Crossy]

1 minute ago, sometimewoodworker said:

... together with the fact that they have virtually no benefits compared to radial finals

Indeed, plus if you have a 2.5mm² ring on a 32A breaker you can gain an "extra" 8A by splitting it and making 2 x 20A radials Cost = 2 x 20A breakers. Handy for those with a single ring to the kitchen.

 

But as I've noted before, don't use ring finals in Thailand.

 

 

[tryasimight]

On 8/28/2017 at 12:01 PM, NilSS said:

MegaHome recently opened a branch a short distance from me and I was delighted to find they stock Siemens RCBOs. I'm a bit perplexed at the reversal of Live and Neutral on them, I guess this is the versatility of the DIN system though, the incomer and mini breakers would just be arranged from right to left instead of left to right. I'm presently constructing another 18 buildings that I'll be wiring myself later in the year. I'd previously been using the Schneider plug in system on earlier builds but I've been unhappy with the reliability of Schneider RCBOs.

 

My family and I just moved into a new house, which I wired in a hurry to get it operational. I used ABB RCD with a separate overcurrent protector. This is wired in TT configuration. I know I get zero out of ten for neatness, but as I said I did this in a real hurry and with cable scraps. I'm still pulled between ABB and Siemens for the new builds, maybe you have some experience with reliability and can comment. I'm leaning towards Siemens. . .

 

 

 

 

The problem with this is the people installing the rods just don't understand what they're doing, farang or otherwise. In 16 years here I've never seen a good job done of grounding, be it badly sized ground conductors, lack of corrosion protection, ground rods that are too short, multiple ground rods used in a way that could cause dangerous touch voltages between grounded surfaces, ground rods buried in concrete so inspection is impossible etc etc, the list could go on forever. If you can't see it and inspect it, it should be assumed it's non-functional or non-existent.

 

 

 

I've seen some truly horrific wiring jobs here. The house we just moved out of originally had an electric shower wired DIRECTLY to the three phase cables on the PEA side, by means of a splice with insulation tape (no breaker of any kind, no means of isolation). Frightening. I don't need to explain this to you of course, you know the deal, but like you I'm quite sincere that I want to help people get their house electrically safe. I mulled the idea of suggesting a list of local 'experts' that forum members could call upon to go take a gander at their electrical system for the price of a chin wag and a beer. The problem is I personally am not really interested in getting involved face to face with other forum members. Every time I see a topic like this though, I just want to go and scream, "This is what you need to do!" 

I guess you were in too much of a hurry to complete the MEN link as well?

[Led Lolly Yellow Lolly]

No, the MEN link is intentionally left out. As I said, this is a TT system. 

[tryasimight]

On 06/02/2018 at 9:14 PM, NilSS said:

No, the MEN link is intentionally left out. As I said, this is a TT system. 

Sorry.... Missed that. But why not used the standard Thai requirements ( as I understand them)  of using the MEN system?

[Led Lolly Yellow Lolly]

I'm single handedly maintaining a private electrical system consisting of 4 x 22,000 volt transformers supplying approximately 60 buildings containing around 200 rooms, 3-phase MDBs and sub panels. It's a phuking nightmare. Presently I'm not happy with the grounding arrangements with the distribution system and the risk of a broken neutral is too great if I use MEN, therefore I've gone with the TT route for the time being.

[bankruatsteve]

So, @Crossy, I remember you saying that MEN is now the requirement in Thailand but is that still a provincial thing?  I haven't seen it implemented anywhere I have been in Isaan and my local PEA hasn't, to my knowledge, made any effort to retro-fit anywhere.  Do you know the plans for that, if any?

[Crossy]

21 minutes ago, bankruatsteve said:

Do you know the plans for that, if any?

I have zero knowledge of what goes on inside PEA, I have little enough knowledge of what goes on inside my own employer.

 

What I do know. MEN, RCD, 1.8m rod and 3-pin outlets are "required" for new installations, you won't (shouldn't) pass the inspection if you don't comply.

 

A new installation being replacement of a "construction" meter with a "permanent" meter, if you already have a permanent meter (you will be paying about 4 Baht per unit for power) nobody is going to inspect anything.

 

In the past I have advised members NOT to go MEN unless they KNOW it's been implemented in their area (check if the neutral is grounded every 3rd pole or so). In this case an RCD is an absolute requirement for shock protection, even if a decent rod is fitted.

 

Unfortunately, it seems that PEA in some areas are failing to actually upgrade the supply infrastructure but are still insisting on the MEN link. All I can suggest for these areas is to put the link in to get past the inspection then remove it if you feel there's a chance of the neutral failing at some point. To be honest the chances of a open neutral (without losing the supply as well), whilst there, are quite slim and the added protection of having MEN outweighs the risk.

 

It is highly unlikely that anyone will be going round existing installations doing any inspections.

 

[bankruatsteve]

1 minute ago, Crossy said:

It is highly unlikely that anyone will be going round existing installations doing any inspections.

 

I wonder if that is THE problem with implementation?  I'm guessing 90% (probably higher) of rural homes neither have CU or a ground.  Would a MEN implementation for those that do (have a CU and ground) be at risk to do so?  For me, there's no way I'm going to connect the main N to my ground bar (I have 2 CU's directly connect to the mains - well, an AVS) but should I link the N bar to E bar to make my system better?

[RichCor]

The electric installations here in Thailand really scare me.

 

I'd suggest extreme caution and thorough testing before retrofitting any install to add MEN.

 

So far, I've rewired three homes and four shop houses, and half have had the Live Neutral incomers reversed, and/or have the in-building wire colors reversed (as in using White or Blue as LIVE).

 

I've also been on the receiving end of open neutrals when working on communications and computer equipment. It's absolutely no fun when you unscrew a peripheral connector only to find its ground shield was the only thing keeping the damn thing on....then fighting to plug it back in just so you can let go.

 

I love RCDs.