More POWAA for my welder

[ion529]

Okay so, I have a shed down the end of my garden where I like to weld and do stupid stuff. Anyway I have an arc welder which at maximum power gives me 160A @ 20V which is 3200W. When my parents built the shed they didn't take into account that there son was going to be a raging metal melting maniac and hence there is just 2 G-pin 13A @ 230V AC sockets in the entire shed, very inconsiderate I know. This of course allows for a maximum of 2990W which just isn't good enough if I want to weld thick steel without the fuse going every 2 seconds.

Luckily the electrician clearly saw my future struggles and popped in a 25A breaker for the shed on the mains board back up at the house when it was built. But here's where things get a little iffy: The cable for the shed comes in though a big dirty black wire from the house underground and goes straight into the G-pin sockets and then a smaller grey wire goes from the sockets to the strip light up above. (I've attached a highly detailed diagram below) I assumed that the strip light was just in parallel with the power coming into the sockets and turning off the power for the shed at the breaker would therefore turn off the sockets and the lights. But alas it only turned off the sockets and the lights are still fully functional. I don't know what witchcraftery this is but I don't really want to open up the socket and have a peak if there's live electricity going through her. My plan was to just attach a big 16Amp connector to the big dirty cable but it seems a bit tricky as I've no idea whats going on inside the socket.

Thanks in advance,

Peter

 

[Intoelectrics]

I'm not hiring an electrician, All I want to know is how the light still turns on if the breaker at my house is off. Surely the explanation to that is simple that I can understand. e.g. "There is 2 sets of wires in the black cable" or "that's not how a breaker works electricity might still flowing". I don't want step by step instructions just why this is happening. Assuming it's not quantum tunneling or some huge EM field providing my light magically with 230VAC I can figure it out

So it sounds like the swa supply cable is multi core and there are "2" circuits from the house to the shed. One for the light and one for the socket. This means there will should be another mcb in the house that protects the additional circuit.

 

[davesparks]

. My plan was to just attach a big 16Amp connector to the big dirty cable but it seems a bit tricky as I've no idea whats going on inside the socket.

You can’t just put a 16A socket on it as you need to install 16A fuse protection or else you risk a fire.

 

[buzzlightyear]

I'm not hiring an electrician, All I want to know is how the light still turns on if the breaker at my house is off. Surely the explanation to that is simple that I can understand. e.g. "There is 2 sets of wires in the black cable" or "that's not how a breaker works electricity might still flowing". I don't want step by step instructions just why this is happening. Assuming it's not quantum tunneling or some huge EM field providing my light magically with 230VAC I can figure it out

you op might be barking up the wrong tree on this post
we are here to assist people like you ,and not to show you how to wire up a light ,so that s the case I'm out .

 

[ion529]

What purpose is the relay serving for the light? I'm intrigued.
And it looks like the armour goes straight into the socket via a stuffing gland - is that correct?

If th eight still functions when the MCB you suspect is feeding it is switched off ,then there is only one answer - the light is not fed from that particular breaker.

I can't see any alternative to getting a sparky in for this. Do let us know what that relay does though. Tell us where the cables into the relay box go to.

This has already been answered for you.
It cannot be fed from the the same mcb as the socket.

Ok so what i'm gathering is there must be two sets of wires inside the black cable to provide an additional source and I need to play around with the breakers until I can turn it off to have a look.

As for the relay i'm assuming it's just so the cables don't have to run all the way down to the switch or the switch can't take 230V/13A and requires a relay to perform that function safely. I have the same setup in my electric foundry where I use a solid state relay to switch the high current although the positioning is very odd I agree.

And for people saying my install is bad. Yes I know that's why i'm NOT hiring an electrician.

 

[ion529]

You can’t just put a 16A socket on it as you need to install 16A fuse protection or else you risk a fire.

I know that, when I say "i'm gonna throw on a 16A plug" I intend to properly wire it with a fuse etc.

 

[DPG]

Thanks for the extra info regarding the light. The normal method would be to use an FCU (often referrred to as a fused spur) to feed the light. This would suitably protect the light and associated wiring. The relay offers no overcurrent protection.

I'm wary of going any further though - I'm all for a bit of optimistic DIY but this is beyond that unfortunately.

 

[ion529]

Things are not looking good for your welder then mate as you only have a 25A breaker. You also suggesting you were going to fit a 16A connector for the 38A welder also does not bode well.

Regarding your light. I would ask your friends/neighbours for a good electrician they have had, and get them to check out the wiring.
Your light must not be wired up to the 25A breaker.

It's not a 38A welder, the welder says the max current it's circuits are rated for is 38A on the input. However its never going to draw near that since its max output is 160A @ 20V and its being supplied by a 230V input. So at max output it draws (160*20)/230 which is 13.9A

 

[ion529]

Thanks for the extra info regarding the light. The normal method would be to use an FCU (often referrred to as a fused spur) to feed the light. This would suitably protect the light and associated wiring. The relay offers no overcurrent protection.

I'm wary of going any further though - I'm all for a bit of optimistic DIY but this is beyond that unfortunately.

I don't intend rewiring the light, just adding a 16A connection. My question has pretty much been answered though, there has to another circuit feeding the light which I can turn off at the breaker.

 

[SparkyChick]

Actually according to the manual (I believe it's a Sealey XT160 Arc Welder?), the output voltage at 160A is more like 24v. 240v/24v = 10. 160A/10 = 16A. The manufacturers instructions clearly state it requires a 16A socket to be used at it's maximum capability.

The 38A stated is likely to be the inrush current when you turn the unit on.

Just remember more amps = less welding due to the duty cycle of the machine. You're far better off using less amps, get more welding time.

If that steel in the vise is an example of what you're welding, you don't need 160A to weld that. I've watched my Dad weld much thicker material than that on a poxy 60A/120A welder he bought in the early 70's. When he taught me to weld I found I got much better results at 60A using thinner electrodes. Unless you require major structural strength, you don't need to penetrate too deep in the metal.

 

[ion529]

Actually according to the manual (I believe it's a Sealey XT160 Arc Welder?), the output voltage at 160A is more like 24v. 240v/24v = 10. 160A/10 = 16A. The manufacturers instructions clearly state it requires a 16A socket to be used at it's maximum capability.

The 38A stated is likely to be the inrush current when you turn the unit on.

Just remember more amps = less welding due to the duty cycle of the machine. You're far better off using less amps, get more welding time.

If that steel in the vise is an example of what you're welding, you don't need 160A to weld that. I've watched my Dad weld much thicker material than that on a poxy 60A/120A welder he bought in the early 70's. When he taught me to weld I found I got much better results at 60A using thinner electrodes. Unless you require major structural strength, you don't need to penetrate too deep in the metal.

Thanks for the help but no thats not what i'm welding, I have very thick steel coming for a hydrogen combustion chamber project which will need high strength and proper penetration

 

[ion529]

Well some of you might find this very entertaining:
I found the breaker the light is on, it's actually wired to half of my living room, a bathroom on the other side of the house and my light thats about 40m down the end of the garden. Now you might understand the electricians i'm dealing with. On top of that I have one circuit thats wired to a single light of 12 in the middle of my living room and also to my attic and bedroom.

 

[DPG]

What certificates have you received for the electrical work you have had done?

 

[buzzlightyear]

I'm not hiring an electrician, All I want to know is how the light still turns on if the breaker at my house is off

you can lead a horse to water ,but a pencil must be lead.

 

[SparkyChick]

Thanks for the help but no thats not what i'm welding, I have very thick steel coming for a hydrogen combustion chamber project which will need high strength and proper penetration

Then I'm sorry to be blunt, but my advice is have it welded by a professional with better equipment than you have there. Pressure vessels of any kind require proper preparation and post welding checks to insure the integrity of the welds. All it needs is a pocket of slag and you could be making a shrapnel machine.

In fact I'll go further and suggest that you don't try burning hydrogen in any form of containment.

With regards to the electrical installation, I can pretty much guarantee that if you'd hired a decent electrician (like the guys who have been offering you advice here), it wouldn't be in the state it's in. As has been highlighted, very often poor work is a result of the client going for the cheapest option.

 

[Spoon]

With regards to the electrical installation, I can pretty much guarantee that if you'd hired a decent electrician (like the guys who have been offering you advice here),

Would need a location first.