Accessing power (240v) directly from the mains.

[rockyysdt]

I've been observing some workmen constructing a covered area to the front of a 2 storey house.

They've erected a number of concrete pillars, and now working on welding a framework of metal beams to support the roofing sheets.

Interestingly the workman removed the cover off the mains fuse box and have directly connected their power cable to this.

I suppose their welder needs high current not supported by the fitted fuses.

Is this dangerous?

See photos attached.

[Tywais]

I've seen worse. Saw an arc welder with just the bare wires stuck into a standard wall socket.

The splice would be of concern if it is just twisted wires and no proper anchor connecting them as it could get hot.

[Soutpeel]

but that seems to be the outlet side of the RCB, so they haven't eliminated the "fuse" for your theory to be correct, they would have had to connect in at the top of the box where the single wire comes in which would would be the supply.

The splice with the tape is not good, but taking the power off directly like this cant see a problem, why not...just added another circuit (the welder) no different from connecting your light circuits or stover etc...

[kannot]

Perfectly safe, many dead Thais will testify to that

[Crossy]

Actually Soutpeel, that's the inlet side of the incomer (it's a Square-D style box with plug-in breakers).

The only overcurrent / short circuit protection is the cable itself

[Soutpeel]

Actually Soutpeel, that's the inlet side of the incomer (it's a Square-D style box with plug-in breakers).

The only overcurrent / short circuit protection is the cable itself

ok my mistake... just as well I am mechanical not electrical then...

[KhunBENQ]

Welcome to Thailand

Is it dangerous? Yes.

Does it happen regularly? Yes.

Do you have a fire extinguisher that can be used on live wires? Guess No

I've seen worse.

Me too.

Our last "craftsmen" (welding a metal roof construction) even walked outside to the street and connected at some point at the meter to save any line flowing to the house.

The next level of protection device from this point might trip at 500 A !? (have no source)

But as @Crossy assumes: the cable will blow up/burn up before the next protection will trip.

When will they throw a wire over the high voltage lines which also pass along

[Naam]

during construction of our home that was the done thing. "we always do it like this" i was told.

[CharlieH]

MOVED to Electrical forum

[thaibeachlovers]

My BIL made a jerry rig directly to the mains with no safety features at all and left the wires exposed to kill anyone that happened to put their hand on it. When I realised what it was I covered it with a plastic box.

However, it came in useful when doing some arc welding as the circuit breakers were too low rated to operate the welder.

[bankruatsteve]

This is case of "Thai electrics 101" where they are taught to do something a certain way and just don't have the education otherwise. When I had some welders come out, they did the same thing even though I assured them they would not hurt my wire (on a 20a circuit). IE: That's the way they know and no farang is going to tell them different.

[rockyysdt]

Thanks Crossy.

I'll keep away from their wires.

Have a shot power point (very loose socket internals).

Have a replacement but looks alien to me.

How do you get to the wiring terminals?

[Naam]

This is case of "Thai electrics 101" where they are taught to do something a certain way and just don't have the education otherwise. When I had some welders come out, they did the same thing even though I assured them they would not hurt my wire (on a 20a circuit). IE: That's the way they know and no farang is going to tell them different.

most welding units which the roof welders use draw much higher amps than 20.

[Tywais]

This is case of "Thai electrics 101" where they are taught to do something a certain way and just don't have the education otherwise. When I had some welders come out, they did the same thing even though I assured them they would not hurt my wire (on a 20a circuit). IE: That's the way they know and no farang is going to tell them different.

most welding units which the roof welders use draw much higher amps than 20.

Yep, 50-60 Amp for a stick welder would not be uncommon. Small MIGs may be in the 20A range but probably not at striking.

Just saw this on another forum.

Q - Is it possible to take two different circuits and combine them?

A - Yes, it's generally referred to as a 'house fire'.

[Crossy]

Thanks Crossy.

I'll keep away from their wires.

Have a shot power point (very loose socket internals).

Have a replacement but looks alien to me.

How do you get to the wiring terminals?

The white plastic bits with the holes in unclip

[rockyysdt]

Thanks

Plastic bits off.

This unit is a triple power point.

They have separate terminals for the third plug?

I'll have to extend power with a couple of short pieces of wire.

Also positive and neutral are at opposite ends with very little access space for wires around the plate.

Good design? haco

[Crossy]

Yeah, I have quite a few of these, it can get tight routing the wires around.

The same base is used for all sorts of combinations (the modules just click in) so you can build whatever configuration of outlets, switches, fan controls, blanking plates etc. that you need. We have several with five 2-pin modules installed, handy for all those phone chargers, lamps, fans etc.

[bankruatsteve]

This is case of "Thai electrics 101" where they are taught to do something a certain way and just don't have the education otherwise. When I had some welders come out, they did the same thing even though I assured them they would not hurt my wire (on a 20a circuit). IE: That's the way they know and no farang is going to tell them different.

most welding units which the roof welders use draw much higher amps than 20.

Yep, 50-60 Amp for a stick welder would not be uncommon. Small MIGs may be in the 20A range but probably not at striking.

Just saw this on another forum.

Q - Is it possible to take two different circuits and combine them?

A - Yes, it's generally referred to as a 'house fire'.

I'm clueless about welding - just to say: The incident with the welders, I asked how much they would draw and the reply was maybe 20 - this was for a door. But, they would have needed to connect a plug to their wires so maybe just easier to do it that way. For all the welding on my house, I bought an inverter type and everything was nicely done via plug-in to 20a circuit never tripping.

[flyingdoc]

Lots of good advice. I will look out in future!

[Laza 45]

...When they were doing the welding for my roof they just hooked up a cable from the meter box directly to the welder.. no probs do it all the time!

[kannot]

This is case of "Thai electrics 101" where they are taught to do something a certain way and just don't have the education otherwise. When I had some welders come out, they did the same thing even though I assured them they would not hurt my wire (on a 20a circuit). IE: That's the way they know and no farang is going to tell them different.

most welding units which the roof welders use draw much higher amps than 20.

Thats correct as what better way to cut steel beams than with the welder

[attrayant]

The splice would be of concern if it is just twisted wires and no proper anchor connecting them as it could get hot.

The first rush of current probably arc-welded them together.

[gandalf12]

In two words very dangerous

[gandalf12]

Thanks Crossy.

I'll keep away from their wires.

Have a shot power point (very loose socket internals).

Have a replacement but looks alien to me.

How do you get to the wiring terminals?

Should be a maximum of three terminals, Live, Neutral and Earth. The Live and Neutral will have connections to the pins that are vertical and the earth is the pin to the side.For hose wiring it doesnt matter which of the stacked pins are Live or Neutral as long as you dont mix them. The front cover should unclip and the terminals will be seen

[rockyysdt]

Earth terminations are there but useless without an earth wire or cable.

Also, it appears most products over here are sold with 2 pin plug leads.

[Crossy]

Should be a maximum of three terminals, Live, Neutral and Earth. The Live and Neutral will have connections to the pins that are vertical and the earth is the pin to the side.For hose wiring it doesnt matter which of the stacked pins are Live or Neutral as long as you dont mix them. The front cover should unclip and the terminals will be seen

Those outlets are made up modules, each with their own terminals, the one shown has 2 modules (one and two outlets), my 5 x 2-pin ones have 10 terminals which need linking, 5 x L and 5 x N.

[louse1953]

It's not dangerous to you if you let a Thai do it.I go straight to the meter and the wire has been hanging there for months.It's to bypass the fuse.

[Barin]

This is case of "Thai electrics 101" where they are taught to do something a certain way and just don't have the education otherwise. When I had some welders come out, they did the same thing even though I assured them they would not hurt my wire (on a 20a circuit). IE: That's the way they know and no farang is going to tell them different.

most welding units which the roof welders use draw much higher amps than 20.

On the welding rod side the current may be as high as 100 Amperes and even more (in the arc itself).

But on the mains side it is much lower as electric welding is using step down transformer.

[KhunBENQ]

On the welding rod side the current may be as high as 100 Amperes and even more (in the arc itself).

But on the mains side it is much lower as electric welding is using step down transformer.

And much more.

Just browsed some Thai sites offering welding machines.

200 A is not the top end.

This fairly small thing is available with up to 160 A and has an input power capacity of 7kVA, so about 30 A input current.

http://www.bp-metal.com/%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B9%80%E0%B8%8A%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%A1%E0%B9%84%E0%B8%9F%E0%B8%9F%E0%B9%89%E0%B8%B2-%E0%B8%95%E0%B8%B9%E0%B9%89%E0%B9%80%E0%B8%8A%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%A1%E0%B8%98%E0%B8%B9%E0%B8%9B-ARC-MMA-Welding/%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B9%80%E0%B8%8A%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%A1-%E0%B8%95%E0%B8%B9%E0%B9%89%E0%B9%80%E0%B8%8A%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%A1%E0%B9%84%E0%B8%9F%E0%B8%9F%E0%B9%89%E0%B8%B2-Roland-Mini-200.html

And as said: this one is not a real big one.

The real big ones need three phase connection, so you won't find them in the semiprofessional/private environment.

[Barin]

On the welding rod side the current may be as high as 100 Amperes and even more (in the arc itself).

But on the mains side it is much lower as electric welding is using step down transformer.

And much more.

Just browsed some Thai sites offering welding machines.

200 A is not the top end.

This fairly small thing is available with up to 160 A and has an input power capacity of 7kVA, so about 30 A input current.

http://www.bp-metal.com/%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B9%80%E0%B8%8A%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%A1%E0%B9%84%E0%B8%9F%E0%B8%9F%E0%B9%89%E0%B8%B2-%E0%B8%95%E0%B8%B9%E0%B9%89%E0%B9%80%E0%B8%8A%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%A1%E0%B8%98%E0%B8%B9%E0%B8%9B-ARC-MMA-Welding/%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B9%80%E0%B8%8A%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%A1-%E0%B8%95%E0%B8%B9%E0%B9%89%E0%B9%80%E0%B8%8A%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%A1%E0%B9%84%E0%B8%9F%E0%B8%9F%E0%B9%89%E0%B8%B2-Roland-Mini-200.html

And as said: this one is not a real big one.

The real big ones need three phase connection, so you won't find them in the semiprofessional/private environment.

20 Ampere input may be connected to standard wall outlet I believe (with care, must have a good plug and no loose connections inside).

To be on the safe side someone should always stay near the outlet to observe if there is no sign of smoke or any suspicious smell.

30 Ampere input and over should be connected directly to the output side of the RCB panel. Never connect to the input side!