Hmm. I think this cable is overloaded...

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Saw this today!!

Eat your heart out, RF!! :lol:

It's 1.5 4 core SWA with EC14's on either end (YUK) and two cores each in L & N, with a 40A breaker. The circuit length is about 10m, with no RCD protection, feeding a detached garage & utility building with several appliances (freezer, washing machines, TD etc). Good, eh?

OverloadedSWA.jpg
 
graicous, And to think it would have been fine if it had RCD protection! :oops:


:lol:
 
erm, did you take the cover off that mini board?

2x 1.5mm²­s is the equivalent of a little over 4mm².. it can take 42A ( 21A per wire.. ) .. 4mm² can only take 38A.. ( table 4D4A in the regs books.. )

consider it a ring feeding one point..
 
ColJack said:
erm, did you take the cover off that mini board?

2x 1.5mm²­s is the equivalent of a little over 4mm².. it can take 42A ( 21A per wire.. ) .. 4mm² can only take 38A.. ( table 4D4A in the regs books.. )

consider it a ring feeding one point..

A 40A ring??

Even a 32A ring has to be wired in 2 x 2.5....

But if feeds a CU. And it's a right f'up of a job. And the clamps. And no RCD protection.

Yes, I did remove the cover.

I have condemned it, anyhow.
 
I'd be more concerned that 2 way wylex standard would turn into a sticky puddle rather than the SWA tbh

At 21A per conductor thats over 40A, granted there will be a grouping factor, but its not going to end up massively under (and what happens with small overloads is the PVC just ages a bit faster than normal due to higher than normal copper temperatures*)

So while I wouldn't install that SWA, I wouldn't put any money on it melting anytime soon :!:

*At larger sustained overloads, it turns into a sticky mess, and there isn't anything to hold the conductors apart anymore which is usually followed by a bit of a bang... :lol:
 
1.5mm² T+E is 20A clipped direct x2 is 40A...
2.5mm² T+E is 27A clipped direct x2 is 54A...

you could get away with it but it is probably for some balancing reason ( IE more than 1 point with un-even current distribution round the ring.. )
or for volt drop or Zs values..


since the cable only feeds one point and is run the same direction and distance then we can safely surmise that current flow in each conductor will be equal..

does the CU it is feeding have rcd's?

while i would have prefered to see glands into an enclosure rather than the earth clamps i'm not sure if that is a reg..
 
ColJack said:
does the CU it is feeding have rcd's?

No.

while i would have prefered to see glands into an enclosure rather than the earth clamps i'm not sure if that is a reg..

The NIC & ECA frown upon that practice, as the glands can crush the cable. They were not designed for that purpose.
 
ColJack said:
while i would have prefered to see glands into an enclosure rather than the earth clamps i'm not sure if that is a reg..

BS 951 is relevant here and by that standard those clamps are only intended for use on rigid pipe, not armour, lead sheathing, etc...

The applicable reg set in this case is 511 (p.84)
 
There were many problems here, but one of the other biggies was a 30A Type 1 shower circuit running two showers not interlocked: an 8.5kW & an 8.0kW unit.... :shock:
 
securespark said:
Saw this today!!

Eat your heart out, RF!! :lol:

It's 1.5 4 core SWA with EC14's on either end (YUK) and two cores each in L & N, with a 40A breaker. The circuit length is about 10m, with no RCD protection, feeding a detached garage & utility building with several appliances (freezer, washing machines, TD etc). Good, eh?

OverloadedSWA.jpg

i like the way there is an ash tray handy for when it eventualy starts smoking :roll: :roll:
 
the nic frown upon swa cable being terminated into swa glands?? :shock: ok then.. :roll:

and how are swa glands not designed for the purpose of terminating swa cable?
 

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