3KW LWD Element wiring advice

[charliefarley]

Just about to wire up one of Lard's elements, but the posts aren't labeled.

It's fairly obvious which one neutral is but not sure which should be live?
One post is longer than the other one...

Also, can I get away with a 13A plug temporarily?

[Belter]

Is it obvious which one neutral is? Should be pretty obvious which one Earth is. The other two can be either live or neutral as polarity isn't important.

Post a photo mate

[charliefarley]

sorry, I meant earth!

[Belter]

Haha good

The other two don't matter. Either way round.

[charliefarley]

The other two can be either live or neutral as polarity isn't important.

Post a photo mate

Great, thought so but thought I'd better check. Thanks

[Belter]

The other two can be either live or neutral as polarity isn't important.

Post a photo mate

Great, thought so but thought I'd better check. Thanks

No worries. Those elements are awesome. I use one In my rims and it comes out clean afterwards.

[BenB]

In terms of the plug. If well terminated it should be okay. Right on the 13a limit but hey. I run 3000 through a 13a without problems even after a 90 main boil.

[Kev888]

Yes, I've run 3kw elements via 13A plugs for years, only had one problem when a plug had a dodgy contact and got too hot, normally they're fine and only get mildly warm even after hours of use. Which frankly is the way it should be as its all within spec.

But I would advise only using decent quality brands of sockets (MK is my favourite, crabtree is also good), the budget sockets don't have the durability I would want for such unusual sustained use. And keep an eye on things, if prongs start to look dirty or worn or if things start to feel hot then there may be a dodgy contact which will cause over-heating. And (as has come up on here before) a double 13A socket is a 13a outlet total, not 26a (amazingly!), so if you have more than one element then use more than one socket.

Cheers
Kev

[Belter]

3000W / 240 = 12.5 amps. I'm sure a few people will be on to argue with me. But any 13A plug should be fine

[BenB]

They can't do 26 but many can do more than 13. MK double sockets for example have been tested (by mk) and shown to be good for 19 amps in total indefinitely. Above that and it's a matter of how long you are pulling the amps.

[Kev888]

Yes, MK are one of the best - I don't think its actually an official/guaranteed rating for normal use, but its still nice to know they are far from being at the limit with 3kw.

Though I wouldn't be so confident with cheapo/inferior brands. IIRC the standards only require them to cope with 19amps under short term extreme conditions, I don't think they'd have a very long life even if routinely used for hours at the rated limit, let alone beyond it.

Cheers
Kev

[themadhippy]

From the mk catalogue

BS1363-2:1995 requires for double socket outlets that both socket outlets have loads applied via test plugs, 1 test plug having a load of 14 amps whilst the other has a load of 6 amps, making a total load of 20 amps on the cable supplying the double socket outlet. The double socket outlet is then subjected to this loading for a minimum continuous period of 4 hours or longer until stability is reached with a maximum duration of 8 hours (stability being taken as less than 1 degC rise within 1 h). The test is passed if neither the terminals / terminations, nor the accessible external surface, increase in temperature by more than 52 degC.

so in a 20c room thats 72c above the 70c limit for pvc cables

[Kev888]

Ah yes, that was it, thanks. So the total test load is 20A, not 19A as I recalled, thanks for the correction.

Those temperatures certainly bring home the difference between using a socket as rated, vs what it could survive.

Cheers
Kev