New house build - electrical system inspection

[unheard]

Is there such a thing in Thailand?

Is it required by law to get done for every new construction prior to sign off?

At least for the permitted builds.

And if there is, is it applicable everywhere or maybe just urban?

 

[jvs]

I have build two houses here in Thailand and have never seen any kind of inspection.

Both houses build with a permit and drawing by architect.

 

[digbeth]

the electric company would inspect any new builds before connection of meters and would refuses connection that's not up to code

[CharlieKo]

There are companies that will inspect a new build and check everything is as it should be. But I have no idea where to find them. there are Thai FB pages that talk about this. Get you Thai wife/girlfriend to search FB.

 

[Bill97]

PEA inspects before giving you a permanent meter or permanent account.  At least they did so twice for rural CM builds,  Mae Rim and Mae Faak Mai.

 

 

Your contractor or electrician may have taken care of it.  It is just a brief look about and a few questions. Re the following quote

 

25 minutes ago, jvs said:

I have build two houses here in Thailand and have never seen any kind of inspection.

Both houses build with a permit and drawing by architect.

 

[MJCM]

10 minutes ago, Bill97 said:

PEA inspects before giving you a permanent meter or permanent account.  At least they did so twice for rural CM builds,  Mae Rim and Mae Faak Mai.

 

 

Your contractor or electrician may have taken care of it.  It is just a brief look about and a few questions. Re the following quote

 

+1

 

both our local builds had an inspection by the PEA before connecting up the “real” meter. In our old house it was just a quick glance but in our current house the inspection took a lot longer but the install passed and we got our meter ????????

[jvs]

16 minutes ago, Bill97 said:

PEA inspects before giving you a permanent meter or permanent account.  At least they did so twice for rural CM builds,  Mae Rim and Mae Faak Mai.

 

 

Your contractor or electrician may have taken care of it.  It is just a brief look about and a few questions. Re the following quote

 

I was living on the property both times and never seen any inspector,

when i got the building permit they said they would come out but no one

ever showed up.Of course this is Thailand and things vary a lot over here.

I was there when the electric was turned on and every thing worked fine.

[Bill97]

41 minutes ago, jvs said:

I was living on the property both times and never seen any inspector,

when i got the building permit they said they would come out but no one

ever showed up.Of course this is Thailand and things vary a lot over here.

I was there when the electric was turned on and every thing worked fine.

Did you see them put the dead rat in your septic tank?

[KannikaP]

My house was built, and I have lived in it since 2012. Looked in the loft area last week to see electric cables twisted together with black tape. Inspections?????

Saying that, never had any electrical problems even though three 12000BTU air cons are on ONE 20 amp breaker.

[unheard]

Here's the reason for my question (in the picture).

 

The contractor has "forgotten" to install an Earth/Ground rod.

He's covered the wire with dirt and called it a day.

I have found about it by accident while digging around the area, looking for other stuff.

I'm not sure if I'm still on the builder's meter.

Assuming PEA comes in for an inspection and does a half-decent check.

Would they even be capable of finding such a problem, if not for the accidental discovery of my own?

I guess they could do that by checking the Earth/Ground resistance.

 

Edited April 22, 2023 by unheard

[Bill97]

20 minutes ago, unheard said:

The contractor has "forgotten" to install an Earth/Ground rod.

He's covered the wire with dirt and called it a day.

So what else has he failed to do or done incorrectly?  This should be a very real concern.  Shoddy welding, left out half the rebar, glue all pipe joints …..

[unheard]

20 minutes ago, Bill97 said:

So what else has he failed to do or done incorrectly?

Speaking of the electrical contractor...

There was another electrical problem that has surfaced during the A/C install.

I've hired a local electrician to verify the A/C guy's claim -  the problem been confirmed and relayed to the builder.

But apparently he didn't bother to check the Earth/Ground resistance.

To be fair I've only asked him to look into the known problem that's been reported by the A/C installer.

Edited April 22, 2023 by unheard

[sometimewoodworker]

1 hour ago, unheard said:

Assuming PEA comes in for an inspection and does a half-decent check.

Would they even be capable of finding such a problem, if not for the accidental discovery of my own?

I think you are vastly overestimating the scope of a PEA inspection. There is no similarity with an inspection in U.K., Europe, USA and one in Thailand. A PEA inspection is, in general, limited to the connection between their meter and your consumer unit, this usually includes checking that the CU breaker is the approved size and that the earth rod is actually not cosmetic but is real. However many inspections are an excuse for a chin wag and no actual inspection occurs.

“you're not in Kansas anymore”

 

 

[captainjackS]

(80km outside Chiang Mai) Last year when we requested a new permanent meter from PEA, they sent an inspector to the house.  He did visual inspection (no test and measurement) of the Earth rod, CU, and routing back to the PEA pole where service conductors were ready to connect.  Approved within a few minutes.  A few days later, a technician showed up to install the meter.  I am not aware of any paperwork or signatures after the initial application at PEA local office.

[bluejets]

15 hours ago, unheard said:

Would they even be capable of finding such a problem, if not for the accidental discovery of my own?

I guess they could do that by checking the Earth/Ground resistance.

It's not rocket science.( at least not for a qualified lecky)

Any check on the main earth would entail tracing the main conductor to the exterior, as you have done.

In almost all installs, it is not possible to physically check the entire run, however this is covered with a resistance check of the conductor itself (not the ground impedance)

Again, as you have done, check has revealed the earth rod was either never installed (quite possible) or it was completely buried under the ground level and corroded or snapped off due to being unsecured. 

 

What should be done, although seldom seen in Thailand, the rod of 1500mm length minimum, is driven into exterior area soil a distance of 1200mm with 300 left above ground. To this is attached the main earth conductor (usually with a tag saying "earth conductor, do not disconnect") either by clamp or stud connection, and the connection coated with a protective coating paint such as Zinc-it. The very top of the rod should then be secured to the building exterior via a galvanised saddle to avoid any mechanical displacement of the main earth conductor. 

 

Testing of the main earth is between the rod itself (copper coated steel) via a trailing lead and the connection at the main switchboard with the earth removed from the neutral link. Measured dc resistance should be less than 1 ohm. Either test the trailing lead resistance first and remove this and the meter lead resistance from the final measurement, or use a meter which has the appropriate zero capability with trailing lead in place. 

 

Testing the exterior ground resistance can be done with a special 4 lead ground resistance meter but does not apply to commercial or residential installations.

This test is usually reserved for installs such as commumications or sometimes hospitals.

 

Your best approach is ensure the earth is done as above, and where applicable (as is 99% of Thailand) ensure men connection is in place. Add to that the use of combo RCBO breakers on all circuits. It is now also a requirement that these RCBO's be of a certain type (not the "days gone by" ac only)

In reference to this......... https://www.worksafe.qld.gov.au/news-and-events/newsletters/esafe-newsletters/esafe-editions/esafe-electrical/2023-newsletters/february-2023/type-ac-rcds-banned-from-30-april-2023

Edited April 23, 2023 by bluejets

[unheard]

6 hours ago, bluejets said:

What should be done, although seldom seen in Thailand, the rod of 1500mm length minimum, is driven into exterior area soil a distance of 1200mm with 300 left above ground.

Thank you for the detailed write-up.

I'll ask my builder to install a 180cm (8ft) copper-clad ground rod combined with a clamp.

 

[Sophon]

26 minutes ago, unheard said:

Thank you for the detailed write-up.

I'll ask my builder to install a 180cm (8ft) copper-clad ground rod combined with a clamp.

 

8 feet is 240 cm, which I believe is also the required length of the ground rod. This illustration is from a PEA/MEA electrical system description posted by Crossy many times:

[digbeth]

I think in some diagram, Thailand code seem to point out that it requires exothermic welding (or other approved method) of attachment of grounding wire to the rod now, other approved method is not depicted? are clamps still ok? 

[Crossy]

I've never heard of anyone being rejected coz they have clamps (we do).

 

[bluejets]

2 hours ago, Sophon said:

8 feet is 240 cm, which I believe is also the required length of the ground rod. This illustration is from a PEA/MEA electrical system description posted by Crossy many times:

Depth of the driven rod is 1200mm as I showed above with 300mm exposed for Australia and we have some of the world's most stringent electrical standards.

If you want to bash in a 2400mm rod then be my guest, it's not going to make any difference and certainly won't hurt.

 

Well, except that you'll most likely split the rod, damage the copper layer and mushroom the end trying to get it down that distance.????

Edited April 23, 2023 by bluejets

[unheard]

22 minutes ago, bluejets said:

Depth of the driven rod is 1200mm as I showed above with 300mm exposed for Australia and we have some of the world's most stringent electrical standards.

OK, I'll ask the builder to get a 180cm rod.

[unheard]

3 hours ago, Sophon said:

8 feet is 240 cm

Thanks, I've mistyped.

I've checked HomePro.

The rode selection on their site is 30cm, 100cm, 180cm, 240cm and 300.

[brianthainess]

2019 my house was finished. PEA came and checked the earth rod was correct length, i believe they are marked.  The rules had changed a month before, my electrician had, had a house pass a month before with no problems but it had changed, any underground cable had to be the triple insulated cable, and all twisted cables from the road/meter 175mts had to be clamped. All I had to pay extra for was the new underground cable. my electrician did the extra work free. .

     NEW UNDERGROUND CABLE to house.

[unheard]

4 minutes ago, brianthainess said:

PEA came and checked the earth rod was correct length, i believe they are marked

A question for everyone...

Are they really marked?

 

Edited April 23, 2023 by unheard

[Crossy]

15 minutes ago, unheard said:

A question for everyone...

Are they really marked?

 

 

At the sharp end

 

We didn't get our 2.4m in all the way (using an SDS hammer and adaptor) so just cut off the top so the cover would fit on the earth pit.

 

Not a word was said by the inspector.

 

If you use the "regulation" exothermic weld to attach the cable any marking will be obliterated anyway.

[unheard]

50 minutes ago, Crossy said:

If you use the "regulation" exothermic weld to attach the cable any marking will be obliterated anyway.

Will speak to the builder tomorrow regarding my discovery ("missing" rod).

Any suggestions on what to ask?

It's a fairly large builder working on multiple houses at any given time.

They've been pretty responsive to my concerns during the build.

 

My house's been permitted and built according to regulations.

I'm kind of confused now after reading @bluejets comments on the reasonable length of the rod.

Yes, If rectifying on my own I would just follow his advice.

 

But in this case it's still fully a responsibility of the builder - the house hasn't been fully finished yet.

Now that I've discovered the problem on my own, should I make a "demand" for the Earth/Ground system to be installed according to Thai regulations (240cm) and not a cm less?

 

How about the exothermic weld?

Should I "demand" that the install is done 100% according to regulations?

Asking since the rod omission is a bad case of negligence on their part.

[sometimewoodworker]

Unfortunately regulations have been quoted that are, as is often the case, drawn up and quoted without (it seems) much local knowledge.

 

Thai regulations are drawn up knowing that local interpretation is usual so don’t believe that rules in one country are necessarily correct here. 
Things that can influence the earthing include but are not limited to 

bonding earth to the structural steel of you foundations 

installing the earth rod into permanently wet soil

trying to hammer a 2.4 meter rod through earth then into a boulder that is 1 metre down

 

The bonding the earth to your steel in the structure was a requirement that has recently been introduced (despite its discovery over 90 years ago) so retired ex electricians are quite likely to deride its use. This is despite it often being a far more effective and lower distance method than the rod banged into the earth.

[bluejets]

The one aspect of the driven earth electrode in the MEN system is purely a method to hold the supply voltage at ground potential, often overlooked, ignored or just plain misunderstood by diluties.

The majority of any fault current (and hence that required to trip the required circuit breaker) in the MEN system travel back via the neutral conductor, not through the many gazillions of ohms impedence of the crappy old clay soil to a pole neutral-earth perhaps a mile away.

In my experience, retired electricians are even more knowedgable and situation aware than any that are current, certainly way above that of a weekend dilute. 

 

With reference to steel work in an installation, it might be of interest that it provides little or no addition to the pathway to the general earth mass, being primarily encased in concrete, it is, in fact insulated from ground.

 

 

 

Edited April 23, 2023 by bluejets

[Crossy]

1 hour ago, bluejets said:

With reference to steel work in an installation, it might be of interest that it provides little or no addition to the pathway to the general earth mass, being primarily encased in concrete, it is, in fact insulated from ground.

 

You may wish to investigate an "Ufer ground" (after Herbert G. Ufer) or "concrete encased electrode". I'm quite surprised that these earthing methods are not common/permitted in Aus.

 

Our building steel (which is contiguous from roof structure into the driven piles) actually measures rather better than the 2.4m (ish) rod using my rather antique, but still functional earth resistance tester. Which probably explains the minimal damage incurred when we took a direct lightning hit to our roof.

 

It's important to understand that, like building regulations, electrical regulations tend to be tailored to local conditions (wet, dry, hot cold etc. etc.) and do not necessarily transfer well between locations. That said, AS3000 is a pretty good match for Thai conditions and methods, but, of course, cannot over-ride the local regs.

[Muhendis]

16 hours ago, Crossy said:

I've never heard of anyone being rejected coz they have clamps (we do).

 

Is that some form of infection?