I am using 4mm2 Cable rated @ 37amp on 230v

Which feeds Two 13A Schneider Double Sockets that I have put on a separate ring.

My four BTC miners run continuous and use 1250watts(5.25Amp) each per machine per plug, when I have arrived back they are all off and the fourth socket at the very has melted.

The sockets are rated at 13A, per double, and my 2500W load per double socket is only 10.8A.

Is the likely cause of this overloading or another common cause such as arching?

Also, being the fourth most-last socket, I am wondering does this give any hints?

 

I am using 4mm2 Cable rated @ 37amp on 230v

Which feeds Two 13A Schneider Double Sockets that I have put on a separate ring.

My four BTC miners run continuous and use 1250watts(5.25Amp) each per machine per plug, when I have arrived back they are all off and the fourth socket at the very has melted.

The sockets are rated at 13A, per double, and my 2500W load per double socket is only 10.8A.

Is the likely cause of this overloading or another common cause such as arching?

Also, being the fourth most-last socket, I am wondering does this give any hints?

How about a photo, and a photo of the plug that was plugged into it, both inside and outside.

 

The only way I see connectors melting down is excessive current or poor connections leading to heating due to current.

Ron

 

UK sockets are made of Urea-Formaldehyde - which can't melt.
A loose wire or loose fuse in the plug would tend to create heat which will conduct down the pin into the socket. That would show up as damage in the plug, which may melt, because not all plugs as UF.

 

Growing up in the UK with 13a ring mains, I was always surprised at the over heating that would occur on the plug/sockets, given the amount of brass used in the pins etc.
When I came to NA and seeing the much smaller amount of brass used in the plug/socket, I definately expected to see the same condition.
But I have never really come across any thing like my UK experiences.

 

Growing up in the UK with 13a ring mains, I was always surprised at the over heating that would occur on the plug/sockets, given the amount of brass used in the pins etc.
When I came to NA and seeing the much smaller amount of brass used in the plug/socket, I definately expected to see the same condition.
But I have never really come across any thing like my UK experiences.

How long is it since you left? Things have gone downhill since then! Sockets used to be a lot better made when they were designed to run 3kW heaters. Now they seem to be engineered to run a phone charger.

 

I don't know UK power standards but with that much power 7/24 I would hardwire my miner (money maker) power connections to a fused disconnect switch. The 100% duty cycle seems be causing thermal effects at the wire/plug/socket connections on some parts of questionable quality.

 

How long is it since you left?

1970.

 

Excuse my incorrect words.

When I say Plug Socket, the actual part that shows melting and burning is inside the schnieder double socket, facia plate where the live wire screws in.

not the appliance end/ plug etc

I can get a photo later

 

I don't know UK power standards but with that much power 7/24 I would hardwire my miner (money maker) power connections to a fused disconnect switch. The 100% duty cycle seems be causing thermal effects at the wire/plug/socket connections on some parts of questionable quality.

I was considering doing somthing like that.


If we allow for some extra draw in my previous calculation, and say 10.8A to 11.5A continuous, is that not suitable for a 13A socket running 24/7

 

Excuse my incorrect words.

When I say Plug Socket, the actual part that shows melting and burning is inside the schnieder double socket, facia plate where the live wire screws in.

not the appliance end/ plug etc

I can get a photo later

I'd guess that the screw wasn't tight. If it was the live side then it's not conducted heat from the plug, as it would have to get through the switch.
If it was a problem with the socket, then both of them would be equally affected.

 

Sorry for the delay guys, here are the pictures of the insde of the socket.

 

Loose wire.
(And if you used a fused spur, a loose wire would have much the same result)

 

Looks like a simple connection failure from a loose wire.

I use proper Ferrules for stranded on these types of electrical connections and the proper torque to tighten solid or stranded with a properly crimped ferrule..
https://www.assemblymag.com/articles/92666-ferrules-prevent-connection-failures

 

Looks like a simple connection failure from a loose wire.

I use proper Ferrules for stranded on these types of electrical connections and the proper torque to tighten solid or stranded with a properly crimped ferrule..
https://www.assemblymag.com/articles/92666-ferrules-prevent-connection-failures

It would be normally be solid core wire, 2.5mm^2, but the TS used 4mm^2, which would be stranded 7/0.85mm.
I’ve never like the 7-strand cables - they tend to move after tIghtening the screw. No-one uses ferrules on them, and I’m not sure how easy they would be to crimp.
4mm^2 stranded would normally be 56/0.3mm and that would work better both with and without the ferrule.

 

Just curious. With the present price of electricity, is that 5kW of BTC mining cost-effective?

 

+1 for a bad connection/loose wire. Since you're using so much current continuously, I'd opt for an old-style socket with screw terminals.

 

Hello,

Indeed, the burning is from a bad/loose contact.
I prefer screw terminals with a loop to hold the wire, like this one used for a PCB:

It can be used with solid and stranded wires.

Bertus

 

So the consensus is Loose wires, however a question - How is the burning caused on the socket interior? Via Arching?
What else could it be caused by?

 

Just curious. With the present price of electricity, is that 5kW of BTC mining cost-effective?

No t isnt at todays rates, but BTC goes up and down so 6 months of losses can turn into profit in a matter of hours