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Replacement fuse box - Advice needed


JohnnyJazz

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We are going through a big house renovation. Based on an initial survey, it seems the electricity was fine. We just asked the electrician to have a more thorough check and to add lights and switches here and there. He's now telling us the job is finished but one thing suprises me is that he hasn't changed the two main fuse boxes. He says there are fine. Below are the pictures, what do you think ?

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post-207807-0-91825000-1426081510_thumb.

Edited by JohnnyJazz
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Forkinhades is of course absolutely correct - but dont let the "Ground" system fall by the wayside! I had new wiring put in for house extensions and made it an absolute necessity to connect up green - third prong -wiring to the new fuse box. This was done. Later inspection found that although the extension carried the green wire to the fuse box - it was not connected to the main fuse box - even the existing fuse box was not earthed!

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Not a lot, basically

Not very safe, you need a safety-cut device (RCD) at the front end. Bare minimum requirements.

I renovated my house also and had it completely rewired with a new fuse box with the RCD. Because the previous owner had no Air/Cons we had to upgrade the electricity supply from 10 to 15 (Amps/Volts not sure of the terminology) this was done by the electricity company and it was then earthed (the choice was mine whether to have it earthed or not as it was a cost of a couple of hundred Baht extra)). Luckily I had the receipt from the first owner for the installation of the first meter which reduced to cost of the upgrade by a few thousand Baht.

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RCD's in Thailand are not always safe and should not be solely relied upon for safety, especially if you do not have a complete earthing circuit. ELCB's don't work either without a complete earth system. The box as it stands looks fine providing you are sensible in the power consumption. By the size of your boxes I would expect that you have a three phase system at a minimum of 60 amps per phase. I have recently added an additional circuit to my house but free issued all the cable, sockets etc. to ensure that I had the correct sizes for the required power consumption expected.

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We have a two story three bed house in a gated moobaan and you should know thta it was the Show House!.

The aircon x 3 are connected somewhere between the meter and the main circuirbreakers.

We found out when we had a Safe-T-Cut RCD installed.

The electrician refused to install a copper ground rod even though I wanted it and would pay whatever it cost.

He was too busy and could only spare the time to install the RCD!

The SAFE_T_CUT wiring diagram clearly showed the need for the earth connection, but this is Thailand and the electricity is not the same as we have in our Farang Countries.!!!!

We recently bought a second house nearby, no RCD and the aircon is connected before the main Circuit breaker!

The only way to properly isolate the electricity from each house is to cut the power at the meter!

I see some expensive rewiring being required!

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It is difficult to see what is in the associated boxes, but general rules about breaker boxes capacity are......

1. the overall amperage supplied to the home. Should be at least 50 amps, but standard in usa is 100 and higher for larger houses. Electrician or electric company should tell you.

2. With, example, "100 amp service" as it is called, that power is, in your case, distributed to two breaker boxes, unknown if each is fed separately from the supply outside on the poles or not; it is even possible but unlikely that, with two boxes, you have three phase power to your house and two boxes are each hooked to a phase, one phase on one and a second phase on the other box. Unlikely, but a qoodthing to know.

3. So between the two boxes you have, say, 100amps, split 50/50. Then, count how many breakers are in each box; the pic seems to be 12 in the first and about 8 in the second one. Each breaker should be rated at 7 or 8amps for normal lighting and outlet service and at 10amps for air con and other heavier loads. The total number of breakers' ratings should equal less than 100 and if more, you should pay for a larger "amp service."

4. You should install the Safe-T-Cut technology, including RCD, also called GFI, for the whole house, meaning in your case, two ... one system for each box. Further safety is available by installing individual RCD/GFI outlets at the socket where the washer, dryer, and any other metal box device is plugged in. Some houses have a separate overload breaker on the air con or other heavy load stuff.

5. You need a whole new metal breaker box if you need new added outlets/lamps that total more than you have total space for. That is, your box may have space to install, say 10 8amp breakers and 2 10amp breakers, 12 slots available for 12 circuits. If you install more than 12 circuits, you need a whole new metal breaker box with more slots for more breakers. That is how you answer your main question about new boxes or not.

Notes.......

-Grounding is another important topic I covered with same pen name which may be archived on this site.

-see http://simple.wikipedia.org/wiki/GFCI

-I recently saw a disturbing situation at a friend's house (yes the friend is a real person). His remote switch, wall mounted, controls his ceiling fan speed. It is a rotary switch with OFF and 3 positions. The switch box in the room caught fire, showed melting inside it, and nearly ignited the wall and furniture. He had Saft t Cut and GFI RCD as well and correctly installed, but because the failure did not over-draw any extra current and did not show leak or connection between the two supply wires, all his safety devices did not help. blink.png The fire burned out without significant damage except fear.

Nick Tesla knew better.thumbsup.gif

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We have a two story three bed house in a gated moobaan and you should know thta it was the Show House!.

The aircon x 3 are connected somewhere between the meter and the main circuirbreakers.

We found out when we had a Safe-T-Cut RCD installed.

The electrician refused to install a copper ground rod even though I wanted it and would pay whatever it cost.

He was too busy and could only spare the time to install the RCD!

The SAFE_T_CUT wiring diagram clearly showed the need for the earth connection, but this is Thailand and the electricity is not the same as we have in our Farang Countries.!!!!

We recently bought a second house nearby, no RCD and the aircon is connected before the main Circuit breaker!

The only way to properly isolate the electricity from each house is to cut the power at the meter!

I see some expensive rewiring being required!

Do not mess with your meter; do not remove the wires, nothing. This is a very dangerous place to work.

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Not a lot, basically

Not very safe, you need a safety-cut device (RCD) at the front end. Bare minimum requirements.

I renovated my house also and had it completely rewired with a new fuse box with the RCD. Because the previous owner had no Air/Cons we had to upgrade the electricity supply from 10 to 15 (Amps/Volts not sure of the terminology) this was done by the electricity company and it was then earthed (the choice was mine whether to have it earthed or not as it was a cost of a couple of hundred Baht extra)). Luckily I had the receipt from the first owner for the installation of the first meter which reduced to cost of the upgrade by a few thousand Baht.

You are talking Amps.

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RCD's in Thailand are not always safe and should not be solely relied upon for safety, especially if you do not have a complete earthing circuit. ELCB's don't work either without a complete earth system. The box as it stands looks fine providing you are sensible in the power consumption. By the size of your boxes I would expect that you have a three phase system at a minimum of 60 amps per phase. I have recently added an additional circuit to my house but free issued all the cable, sockets etc. to ensure that I had the correct sizes for the required power consumption expected.

What means "free issued" ???????????

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RCD's in Thailand are not always safe and should not be solely relied upon for safety, especially if you do not have a complete earthing circuit. ELCB's don't work either without a complete earth system. The box as it stands looks fine providing you are sensible in the power consumption. By the size of your boxes I would expect that you have a three phase system at a minimum of 60 amps per phase. I have recently added an additional circuit to my house but free issued all the cable, sockets etc. to ensure that I had the correct sizes for the required power consumption expected.

What means "free issued" ???????????

I went and purchase the cable, fittings etc. myself and then gave it to the 'electrician' to install, that way I knew the cable was correctly rated and the fittings were reasonable quality. Only paid the 'electrician' for labour. Does that help.

On another tack three phase in Thailand is not the same as three phase in the UK or USA if it comes to that. Depending upon your property requirements you can have either a single power line installed or three separate power lines. With three power lines they are still installed to the same distribution box but the outlets are split three ways, each one rated at 60 amps in Thailand. Care needs to be taken to ensure that the circuits are kept separate and cannot be connected together.

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We have a two story three bed house in a gated moobaan and you should know thta it was the Show House!.

The aircon x 3 are connected somewhere between the meter and the main circuirbreakers.

We found out when we had a Safe-T-Cut RCD installed.

The electrician refused to install a copper ground rod even though I wanted it and would pay whatever it cost.

He was too busy and could only spare the time to install the RCD!

The SAFE_T_CUT wiring diagram clearly showed the need for the earth connection, but this is Thailand and the electricity is not the same as we have in our Farang Countries.!!!!

We recently bought a second house nearby, no RCD and the aircon is connected before the main Circuit breaker!

The only way to properly isolate the electricity from each house is to cut the power at the meter!

I see some expensive rewiring being required!

Do not mess with your meter; do not remove the wires, nothing. This is a very dangerous place to work.

I do understand that, however, the meter is the Only place to isolate the property from electricity!

If we open the main breakers, the 3 aircon units are still live.

Not nice in a fire/water situation!

The builders and their workers don't give a rats arse about safety.

As cheap as possible to maximise profit!

That is THE only rule truly followed"

Anyway, who likes safety?

It costs money to achieve and inconvenience if applied.

All those nice anti surge socekts to protect your TV and computers etc. all cause a small earth leak so unless your earth leackage kit has a sensitivity control, it may make many false trips.

Annoying if you are away for a few days and return to find the freezer defrosted.....

But seriously, it's considerations like that that cause many to avoid safety!

It never happens to them - until it does, then blame a Farang LOL

Edited by laislica
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On another tack three phase in Thailand is not the same as three phase in the UK or USA if it comes to that. Depending upon your property requirements you can have either a single power line installed or three separate power lines. With three power lines they are still installed to the same distribution box but the outlets are split three ways, each one rated at 60 amps in Thailand. Care needs to be taken to ensure that the circuits are kept separate and cannot be connected together.

Actually Thailand is 3-phase 4-wire, the same as the UK. When you get 3-phase you get 4 wires, 3 phases and one neutral.

Voltages are 220V phase-neutral, 380V phase-phase.

In use, 220V appliances are connected between one of the phases and the neutral. True 3-phase appliances don't necessarily need the neutral so it is left unconnected (and insulated of course).

EDIT Note that there are a small number of villages which are 3-phase 3-wire, 220V phase-phase, but it is an increasingly small number.

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Not trying to shake anyone's timbers, but I just want to put it out that RCD (RCBO, GFI, etc.) protection does not make something "safe". Same as an air bag does not make a car "safe". An RCD/air bag reduces the chance of serious injury when shit happens. Like an air bag 99.9% of people having that will never need it. Same with RCD. On the other hand, when it comes to electricity, a good ground will definitely provide a safety outlet when a fault occurs AND it is properly connected.

While I'm guessing, I think the highest incident of electrical problems are fires due to loose connection (sparking) which an RCD or MCB would not detect.

Just saying: don't think you're "safe" just because you have RCD and you don't need to think you're in danger if you don't have RCD.

As in most cases, safety depends on the person - not the thing.

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^ Sorry Steve but for Thailand you are wrong, mainly because it is near impossible to get a good enough earth, to provide disconnection TIMES quick enough to save someone's life. This is why it is very important to have a front end RCD as a bare minimum, and indeed is a requirement of the PEA.

Please see the pinned thread for a full explanation!

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Proper grounding and installed RCDs are complementary.

Their protections do overlap, but one is not a total substitute for the other, which is why most of the advanced national regulations prescribe the use of grounding AND RCDs.

Neither alone will protect in all situations, in truth even with both you are not 100% certain not to die, but you're pretty close smile.png

As an example, sticking a knife in your toaster and touching a live element, no amount of grounding will protect you from a serious shock, an RCD will likely save your life.

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As an example, sticking a knife in your toaster and touching a live element, no amount of grounding will protect you from a serious shock, an RCD will likely save your life.

.... but it will still hurt like crazy, and you'll have ruined your toast :)

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As an example, sticking a knife in your toaster and touching a live element, no amount of grounding will protect you from a serious shock, an RCD will likely save your life.

.... but it will still hurt like crazy, and you'll have ruined your toast smile.png

Indeed it will, that's something else many do not understand. An RCD will not save you from a shock if you touch a live wire but it has a good (not 100%) chance of stopping you actually dying from said shock.

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Just to be clear, with an RCD installed your earth value can be as high as 1667 ohms, and you will have full protection.

A 20A circuit on a C curve MCB installed without RCD protection will require an earth value of 1.15 ohms to open in the TIME specified in any regs.

Even with MEN connections it is very unclear that these values can be achieved at the DB, let alone at the end of the circuit where the fault might occur

With TT systems here in Thailand you are going to be very lucky to get an external (Ze) earth rod value of less than 20 ohms.

Without the proper test equipment you will not know the value of your earth, which is quite possibly why the PEA insist on front end RCDs and MEN connections. With the onus on the consumer to to this.

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Just to be clear, with an RCD installed your earth value can be as high as 1667 ohms, and you will have full protection.

A 20A circuit on a C curve MCB installed without RCD protection will require an earth value of 1.15 ohms to open in the TIME specified in any regs.

Even with MEN connections it is very unclear that these values can be achieved at the DB, let alone at the end of the circuit where the fault might occur

With TT systems here in Thailand you are going to be very lucky to get an external (Ze) earth rod value of less than 20 ohms.

Without the proper test equipment you will not know the value of your earth, which is quite possibly why the PEA insist on front end RCDs and MEN connections. With the onus on the consumer to to this.

Thanks for your super detailed explanations, cor, fair takes me back to City n Guilds B Cert in Installation and Regulation Technology

- See I got an Ology LOL

but I never went into the trade after finishing my 6 year apprenticeship.

Mind you, it was the 13th edition so things have moved along quite a lot LOL

I wouldn't pass now for sure.

Put me in the class of "A little knowledge - just enough to be dangerous"

But please tell me, just how illegal is it in Thailand to have Aircon (or anything else for that matter) connected BEFORE the MCB and without any isolating main switch? and would there be any recourse I could take against the builder or is this - just the way things are here?

Are there any regulations that I could access and then quote?

We bought the house 3 years ago but it was already 2-3 years old as it was the show house.

Rewiring will be painful as the whole house has wallpaper and wood style cornices between the ceilings and walls, wiring is probably hidden behind them.....

Wiring is surface mounted and papered over...

Cheers

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Sadly not at all ^^^, there are no legally enforceable domestic wiring regs here.

If done from new it should have failed the MEA/PEA inspection for a permanent supply, that said, our "inspection" was the PEA chap gassing with the missus for an hour.

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Sadly not at all ^^^, there are no legally enforceable domestic wiring regs here.

If done from new it should have failed the MEA/PEA inspection for a permanent supply, that said, our "inspection" was the PEA chap gassing with the missus for an hour.

Thanks.

Probably allowed to "Do" their own inspections eh?

Bit like the UK Garages that can MoT their second hand cars LOL

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^ Sorry Steve but for Thailand you are wrong, mainly because it is near impossible to get a good enough earth, to provide disconnection TIMES quick enough to save someone's life. This is why it is very important to have a front end RCD as a bare minimum, and indeed is a requirement of the PEA.

Please see the pinned thread for a full explanation!

A good earth doesn't need to trip a breaker - it just needs to disperse a fault. I'm pretty sure that will be the case even in Thailand. But, that wasn't my point. My point was that having an RCD does not inherently make a dwelling "safe". Nor does not having one make a dwelling "unsafe". I agree a front end RCD is best practice but I would argue that there are some circuits (like lighting, washing machine, fridge, A/C, etc.) that just don't need it. That's where I would go with split boxes: one with RCD one without.

Maybe where you live the PEA requires RCD but where most people live there is not. If not having RCD protection was unsafe and dangerous, then the population in Isan, for example, should be much less than it is - because almost nobody has RCD and electrocution deaths are not common.

I have no argument that RCD protection is best practice. My argument is that it does not make something "safe". And the lack of it does not make something "unsafe".

That's all.

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The requirements by the PEA to have a Front End RCD installed, is only a few years old. Crossy can maybe advise when this happened.

Secondly if you are relying on a TT earth, whose Za (impedance of rod) is 20 ohms. Then ohms law tells us that under fault conditions only 11.5 Amps can flow to earth, thus a 20 Amp MCB will not open under fault conditions.

So a Front End RCD is essential.

Who knows what the figure is of how many people have died through electrocution. One thing is for sure, they certainly all don't get reported.

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I can give a example of this of something that happened when I was upgrading my car port roof.

At the time my electrical system had a TT earth (earth rod), and MEN was not connected, the system was protected by a dual RCD 17th Edition Crabtree Distribution Board, which also had 3 MCBs which were not protected by RCD, which is handy for my essential circuits, but back to point. The builders were installing the steel framework for the roof, on top of my existing ringbeam which was concrete with electrical conduits inside for the lights. They had their welder plugged in, and was welding away quite happily. So I left them to it. I returned a few hours later, and they was complaining that they was getting shocks of the new framework. I was at first puzzled by this, but after investigating I turned out that they had welded the new framework directly onto the live cable inside the conduit. A perfect weld, absolutely incredible.

What they did at the time was to take the cable that was feeding their equipment (one of my final circuits) from the RCD side to the MCB side that was not protected by RCD, as their equipment kept on opening the RCD!

So they was in effect sitting on live framework, and was passing up steel beams from the floor up to the roof!!!

How 2 or even more of the workmen did not killed was a miracle.

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