Domestic Electrical Wiring

[Crossy]

Sorry dragons, re-reading your post in light of your latest:-

If you have an A/C then the smallest practical meter would be a 15/45, fused at 63A.

Buy components from big name suppliers (Square-D, Haco, Panasonic etc.).

With only 2 rooms a single lighting (1.5mm² cable, 10A breaker) and a single outlet (2.5mm² cable, 20A breaker) circuit would suffice, separate circuits for the A/C and water heater if you have one (cable and breaker depending upon size of A/C and heater).

The ground spike is the source of your ground and is an absolute requirement. All outlets must be 3-pin and have the ground connected, grounding of the water heater and A/C is also not negotiable.

A 63A RCBO as the incoming breaker will provide over-current and earth leakage protection for the whole home.

For such a simple installation a good quality surge arresting traily lead would probably be most cost effective.

[electau]

Circuit requirements. mininum.

1 lighting circuit 10A 1.0sqmm

2 power, socket outlets 16 or 20A, 2.5sqmm.

1 HWS 20A, 2.5 sqmm.

Aircons 1 per circuit min 16A 1.5sqmm,actual protective device size and cable size dependant on actual load current. Same with any other permanently connected equipment over 10A.

Mains size minimum 10sqmm Cu PVC/PVC. Protection 50A MCB for 16sqmm 63A.

All circuits protected by 30mA RCDs or RCBOs. All socket outlets earthed and all permanenly connected equipment earthed, eg, aircons, hws, etc.

Main earth and earth electrode to required standard.

TT earthing ( no MEN bonding at main earth bar and main neutral link).

[haveaniceday]

Doh, seems when to many TV threads are open, they don't like to 'send'. Anyway, questions redone.

Regarding post #691

If you have an A/C then the smallest practical meter would be a 15/45, fused at 63A.

Curious about the comment "fused at 63A"

Is the fuse in the meter, or the fuse wire in the knife switch, the main breaker in the consumer unit before the RCBO and individual breakers, or something else?

For such a simple installation a good quality surge arresting traily lead would probably be most cost effective.

What is a "arresting traily lead"?

For surge protection, I was planning on having a surge protector that looks like a 'big over grown CB ' before the consumer unit for each live inbound cable from the street, (3 phase-4 cable- splitting into 3 X single phase circuits each with own board and RCBO).

Also, curious, what do you call a 'thingo' that is on my side of the meter, that is apparently to help if the Gov Mains are hit by lightning, the N is hard wired to the earthing stake at the bottom of the pole, and each N has a device about the size of a chickens egg attached to it, it may be lost in translation, but I think these may self sacrifice and put the energy to the earth in a worse case situation. What is this thing all about, and what is it called?

And by the way, also a tanks to electu for your tips. I see you very active here as well.

[electau]

Ref #693

Service fuses are not used in Thailand. Metering is on the line side off the main switch.

The reference here is to a 63A main circuit breaker. This will give overload protection of the mains and short circuit protection on the load side of the MCB. Your mains should be PVC/PVC.

Service fuses are to protect the mains and metering from short circuit and are a disconnection point for supply. They are supplied by the electricity authority.

[Crossy]

Regarding post #691

If you have an A/C then the smallest practical meter would be a 15/45, fused at 63A.

Curious about the comment "fused at 63A"

Is the fuse in the meter, or the fuse wire in the knife switch, the main breaker in the consumer unit before the RCBO and individual breakers, or something else?

Yes to all the above In the UK it would be suppliers fuse in the service head that protects the meter, since we don't seem to have suppliers fuses here it's up to us to protect the incoming cable (ours anyway) and the meter. Using an incoming breaker or fuse of 63A or so seems popular for a 15/45 supply and will allow a reasonable overload margin whilst still saving the meter from meltdown.

For such a simple installation a good quality surge arresting traily lead would probably be most cost effective.

What is a "arresting traily lead"?

One of these:-

http://www.belkin.com/uk/IWCatProductPage.process?Product_Id=135031#

For surge protection, I was planning on having a surge protector that looks like a 'big over grown CB ' before the consumer unit for each live inbound cable from the street, (3 phase-4 cable- splitting into 3 X single phase circuits each with own board and RCBO).

Sounds like a plan

Also, curious, what do you call a 'thingo' that is on my side of the meter, that is apparently to help if the Gov Mains are hit by lightning, the N is hard wired to the earthing stake at the bottom of the pole, and each N has a device about the size of a chickens egg attached to it, it may be lost in translation, but I think these may self sacrifice and put the energy to the earth in a worse case situation. What is this thing all about, and what is it called?

They are called MOVs (Metal Oxide Varistors) and yes they do tend to be sacrificial in the event of a direct strike.

I think the egg thing is actually a line tap to connect the earthing cable (part of the MEN system) to the grounding wire.

[MichaelJohn]

I'd appreciate some electrical help :-)

I'm pretty good with DIY but useless with electricity.

We're in the final stages of building a house and the electrician has been in and pulled most of the cables through ready for final fixing. All the cable is 2.5mm2.

My question is whether this cable is "thick" enough for the water heaters (2 off at 3.5 and 4kw each) and the oven (which states requires no.4 cable - don't know what that is?)

Any help much appreciated.

PS he does seem a "nice guy", competant and trustworthy but ....................

[Crossy]

Assuming you have one cable and breaker for each heater then 2.5mm² is just big enough for a 4kW heater, should pull about 18A put it on a 20A breaker to protect the cable. There's no upgrade path when you decide you need more oomph though

What is the rating (Amps or kW) of the oven? I'm not sure what they mean by 'No.4' cable, is it just an oven or a full stove with oven and hob?

[MichaelJohn]

Thanks Crossy.

I didn't know what no.4 was either - but it's the spec on the HomePro kitchen layout for the builder/plumber/electrician?

Unfortunatley I'm not sure of the AMPS of the oven (the box is currently burried amonst several others) but it is just a basic oven (B14k) no hob, not electrocnic etc

[Crossy]

No.4 would normally refer to 4 AWG, but that is around 20mm² a bit big for an oven.

Assuming they actually mean 4mm² you'll want it on a 30A breaker, is the oven really over 4kW?

[MichaelJohn]

Crossy, have been to the Kitchen designers today and queries the "no.4 wire" and yes, they mean 4mm - so the 2.5mm the electrician put in will need to be changed. (they did say however that 2.5Sqmm would be okay for the oven but they spec 4mm for safety - which is good :-)

Many thanks for your input, much appreciated.

[electau]

The protective device , an MCB, the overcurrent rating of the device must not exceed the current rating for the cable, (depending on the method of installation).

For a 2.5sqmm this is normally 20A, for 4 sqmm it is 32A.

The Main MCB on the switchboard eg 63A will protect the incoming mains and metering from overload as the MCB must trip at 1.45 rated current.

It will NOT protect the incoming mains from a short circuit fault.

SPDs will only provide surge protection, NOT protection for a short circuit fault.

To protect the incoming mains a protective device, normally an HRC fuse is installed on the line side of the metering. This is the responsibility of the supply authority, not the consumer.

[bankruatsteve]

Crossy, have been to the Kitchen designers today and queries the "no.4 wire" and yes, they mean 4mm - so the 2.5mm the electrician put in will need to be changed. (they did say however that 2.5Sqmm would be okay for the oven but they spec 4mm for safety - which is good :-)

Many thanks for your input, much appreciated.

You really need to find out how many amps your oven draws at maximum. I put in 10mm for my oven but then found out it only needed 2.5. You only need the rated wire size for the amps. Larger does not mean "safer".

[electau]

The Full Load current in amps and/or the rating in watts is on the equipment nameplate with the model and serial number. W/220 = Amps. A* 220 = W.

Equipment should be earthed with a protective earth conductor.

Earthing and correct circuit protection is there for your safety, not the size of conductor in itself.

[Wally66]

New to the forum. Building a new home in Issan and had the idea to place two sets of cable around the perimeter of the property. One for the garden and one for the house. Is it a good idea to place both sets in one PVC pipe?

[Crossy]

New to the forum. Building a new home in Issan and had the idea to place two sets of cable around the perimeter of the property. One for the garden and one for the house. Is it a good idea to place both sets in one PVC pipe?

Welcome to the madhouse Wally.

Should be no issue whatever provided the pipe is big enough.

[electau]

Consumers mains from the metering point to the main switchboard should be installed in a separate conduit as they are unprotected (no service fuse) and should be PVC insulated/PVC sheathed cables.

Other cables run from the main switchboard ie final subcircuits may be run in a common conduit if required, eg outside lighting and power.

[thaibeachlovers]

Sorry, but can't see the attachment / diagram on the OP. Is it hiding somewhere?

BTW, sometimes it's necessary to walk on the wild side! When I came to the present abode, found that someone had wired up a circuit on the outside of the house that did not go through any protective device ( and had no cover, so fairly lethal ). I promptly enclosed it in a plastic box so no one could access it.

However, when the local welder came, the only plugs we have are rated 10 amps as all wiring is on 2 10 amp breakers, so tripped out all the time. So, I had to open up the very dangerous circuit and use that for the welder. Rubber gloves de rigeur!

[Crossy]

Sorry, but can't see the attachment / diagram on the OP. Is it hiding somewhere?

Diagram, like our OP is long gone from Thaivisa.

[IMHO]

I am looking for the adapter for the "Schuko" plug. I have been to every electrical shop where I live, and no one has them. I even printed a picture of the adapter from Crossy's site and took it with me to show them. No joy.

OK.

Adaptors are still available in HomePro

Made in China by Wonpro, part number WA-GF(R5B). Packaging looks like this :-

attachment

On a board with loads of other adaptors, not cheap though, 69 Baht.

Have been searching for these without any luck - anyone know a vendor currently selling Shucko to TIS 3-pin adaptors?

[thaibeachlovers]

I am looking for the adapter for the "Schuko" plug. I have been to every electrical shop where I live, and no one has them. I even printed a picture of the adapter from Crossy's site and took it with me to show them. No joy.

OK.

Adaptors are still available in HomePro

Made in China by Wonpro, part number WA-GF(R5B). Packaging looks like this :-

attachment

On a board with loads of other adaptors, not cheap though, 69 Baht.

Have been searching for these without any luck - anyone know a vendor currently selling Shucko to TIS 3-pin adaptors?

Saw some in Home Pro last time I was there. If you live in/ near Chiang Mai, top floor of Robinsons in the Airport Mall.

You can always buy the socket and wire it in permanently. Home Pro has them.

[IMHO]

I am looking for the adapter for the "Schuko" plug. I have been to every electrical shop where I live, and no one has them. I even printed a picture of the adapter from Crossy's site and took it with me to show them. No joy.

OK.

Adaptors are still available in HomePro

Made in China by Wonpro, part number WA-GF(R5B). Packaging looks like this :-

attachment

On a board with loads of other adaptors, not cheap though, 69 Baht.

Have been searching for these without any luck - anyone know a vendor currently selling Shucko to TIS 3-pin adaptors?

Saw some in Home Pro last time I was there. If you live in/ near Chiang Mai, top floor of Robinsons in the Airport Mall.

You can always buy the socket and wire it in permanently. Home Pro has them.

I have a place there, but only stay there in the cold season and didn't go last year, will look around BKK though, thanks.

Isn't top floor @ Airport Plaza a Power Buy, and HomePro at BigC Extra, or have things changed?

[thaibeachlovers]

OK.

Adaptors are still available in HomePro

Made in China by Wonpro, part number WA-GF(R5B). Packaging looks like this :-

attachment

On a board with loads of other adaptors, not cheap though, 69 Baht.

Have been searching for these without any luck - anyone know a vendor currently selling Shucko to TIS 3-pin adaptors?

Saw some in Home Pro last time I was there. If you live in/ near Chiang Mai, top floor of Robinsons in the Airport Mall.

You can always buy the socket and wire it in permanently. Home Pro has them.

I have a place there, but only stay there in the cold season and didn't go last year, will look around BKK though, thanks.

Isn't top floor @ Airport Plaza a Power Buy, and HomePro at BigC Extra, or have things changed?

Yes and yes, but there is a lot more than Power Buy on the top floor of Robinsons.

[justben]

I am urgently seeking a female shuko socket that can be put on the end of an extension cord. I need to plug it into this:

I had been around Chiang Mai in many shops big and small and found a plastic socket but it was no Shuko and the diameter was too big, so it doesn't fit into this recepticle.

What I need looks like this:

I need this extremely urgently. If anybody has one available please let me know ASAP. Thanks.

[IMHO]

I am urgently seeking a female shuko socket that can be put on the end of an extension cord. I need to plug it into this:

I had been around Chiang Mai in many shops big and small and found a plastic socket but it was no Shuko and the diameter was too big, so it doesn't fit into this recepticle.

What I need looks like this:

I need this extremely urgently. If anybody has one available please let me know ASAP. Thanks.

Try the Amorn store near the Ford dealership on the outer moat road. There's also a smaller Amorn in the carpark of Big-C Extra, but it doesn't stock as much.

Failing that, try RS Components (online only): http://thailand.rs-online.com/web/c/?searchTerm=cee7&sra=oss&r=t

Direct link to what you're looking for: http://thailand.rs-online.com/web/p/trailing-sockets-power-distribution/0327181/

[justben]

I am urgently seeking a female shuko socket that can be put on the end of an extension cord. I need to plug it into this:

I had been around Chiang Mai in many shops big and small and found a plastic socket but it was no Shuko and the diameter was too big, so it doesn't fit into this recepticle.

What I need looks like this:

I need this extremely urgently. If anybody has one available please let me know ASAP. Thanks.

Try the Amorn store near the Ford dealership on the outer moat road. There's also a smaller Amorn in the carpark of Big-C Extra, but it doesn't stock as much.

Failing that, try RS Components (online only): http://thailand.rs-online.com/web/c/?searchTerm=cee7&sra=oss&r=t

Direct link to what you're looking for: http://thailand.rs-online.com/web/p/trailing-sockets-power-distribution/0327181/

I've been to the Amorns, they do not have them.

RS Online seems to be the only option.

Thanks for you help!

[Crossy]

Would item YC-DAX-3 on this page do the trick?

http://www.hacothailand.com/product-thshow.php?setype=10&setype2=1238

There's a slightly different one on the second page which looks very like your sample.

Your local electrical retailer should be able to order for you.

[JoePai]

The protective device , an MCB, the overcurrent rating of the device must not exceed the current rating for the cable, (depending on the method of installation).

For a 2.5sqmm this is normally 20A, for 4 sqmm it is 32A.

The Main MCB on the switchboard eg 63A will protect the incoming mains and metering from overload as the MCB must trip at 1.45 rated current.

It will NOT protect the incoming mains from a short circuit fault.

SPDs will only provide surge protection, NOT protection for a short circuit fault.

To protect the incoming mains a protective device, normally an HRC fuse is installed on the line side of the metering. This is the responsibility of the supply authority, not the consumer.

I am having my home built now and the electrician is installing the wiring etc. Usual size 3 bed house with 3 A/C’s, oven, water heaters etc.

The MCB I noticed is a 63 Amp and I asking him about the Government meter. Keeping in mind we are in Udon he said 15 Amp to which I said too small, want a 45 Amp meter (is that correct ?) However he came back to say “no have, they only give 15 Amp” !!

[Crossy]

A '15 Amp' meter is normally a 15/45 which is the regular one for most homes, PEA insisted that ours was fused at 50A, you may get away with 63A.

Do verify that they want to install a 15/45.

A 5/15 just won't cut it for anything bigger than a shed, next bigger official size (and the largest domestic single-phase available) is a 30/100 which would be fused at 100A.

[JoePai]

Thank you