Can I draw 20A from a double wall socket?

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timmmay

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#252907 16-Jul-2019 18:58

Can I plug two heaters (or even one 2400W / one 1200W) into a single wall socket? I know this end of the house (an extension) has capacity to run at least a 30A load, I just don't know how much I can draw from a double socket. I know each socket is rated 10A, but I don't know if that's per wall outlet or per socket.

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#2277902 16-Jul-2019 19:08

Hi assuming it's on a 20a mcb and via 2.5mm tps, but what we don't know is length. Then we still are limited to 10a per faceplate, not socket, but 20a on an entire circuit.

Where does the 32a bit come from, unless there is 4mm or greater tps involved then 20a it will be.

Cyril

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#2277905 16-Jul-2019 19:13

You can, but expect problems, if your lucky the only problem will be the circuit breaker tripping after some time.

If you not so lucky (and more likely to happen the longer the heaters run), and this depends on a lot of things, like the age of the house wiring, the distance between the distribution board, the size of the wiring, and the size of the circuit breaker

outlet has a melt down

wiring has a melt down

circuit breaker overheats and eventually burns out

house catches on fire.

timmmay

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#2277913 16-Jul-2019 19:32

Ok, thanks guys. It's about 10M from switchboard, probably rewired in the 70s.

My neighbor is an electrician, I'll ask him to have a look one day.

Jase2985

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#2277916 16-Jul-2019 19:42

timmmay:

My neighbor is an electrician, I'll ask him to have a look one day.

doesnt change the fact its rated for 10amps per face plate

timmmay

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#2277919 16-Jul-2019 19:59

Jase2985:

timmmay:

My neighbor is an electrician, I'll ask him to have a look one day.

doesnt change the fact its rated for 10amps per face plate

Ah I didn't understand the earlier reply, thanks for pointing it out. I looked at the socket specs, and yes it does say 10A per faceplate.

Thanks all.

sqishy

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#2277933 16-Jul-2019 20:20

For two heaters 1x2400W and 1x1200W you need a 15A double power point, suitable fuse and electrical cable. Your electrician would be able to advise.

Delphinus

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#2277939 16-Jul-2019 20:47

I guess it all depends on the power point. I had some installed in the garage and was advised 10A on each plug (so 20A across them both). To be fair they are sitting about 1cm from the mini fusebox which goes back to the main switchboard via a 6mm TPS (I think, it's pretty thick).

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mclean

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#2278217 17-Jul-2019 11:36

Delphinus: I guess it all depends on the power point. I had some installed in the garage and was advised 10A on each plug (so 20A across them both). To be fair they are sitting about 1cm from the mini fusebox which goes back to the main switchboard via a 6mm TPS (I think, it's pretty thick).

True, it does depend on the outlet - some are better quality than others. But it doesn't alter the fact a twin 10A socket outlet is rated at 10A total, NOT 10A per outlet. When it's temperature tested for compliance with the standard it's tested at 10A (plus 10%) through a SINGLE outlet. Same for a quad-outlet.

Dynamic

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#2278695 18-Jul-2019 09:24

I had a tenant run a clothes dryer and a heater from a double-outlet... they called me because of a burning smell. The outlet was charred when I arrived. I'd have expected the breaker to trip, but it didn't.

For me is was a 'duh, what did you expect' kind of moment, though I didn't say that out loud. Thinking about it later, for someone with no exposure to electrical theory, a plug is a plug, an appliance is an appliance, and the concept of the total electrical load never enters their head.

So, I'd put this in the 'there is no such thing as a dumb question about electricity' basket. Safety first.

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irongarment

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#2278735 18-Jul-2019 10:12

mclean:
Delphinus: I guess it all depends on the power point. I had some installed in the garage and was advised 10A on each plug (so 20A across them both). To be fair they are sitting about 1cm from the mini fusebox which goes back to the main switchboard via a 6mm TPS (I think, it's pretty thick).

True, it does depend on the outlet - some are better quality than others. But it doesn't alter the fact a twin 10A socket outlet is rated at 10A total, NOT 10A per outlet. When it's temperature tested for compliance with the standard it's tested at 10A (plus 10%) through a SINGLE outlet. Same for a quad-outlet.

That makes no sense. The outlets are rated at 10A each. If I run a wire from the fuse board to a single outlet then I can draw up to 10A, fine. If I continue that wire to another single outlet I can draw 10A from that one too. If both outlets are together in the same box then it's still 10A each. Of course the limiting factor is the circuit breaker, which is 16A, so I could try drawing 10A from each socket on a double outlet, but the breaker would trip.

Also, since nobody knows this magic rule that it's '10A total for a double outlet' [citation needed], and that some outlets are 'better quality than others' (no, they ALL meet the same standard) then it's not unreasonable to believe that people would expect to be able to draw 10A from each socket (limited only by the circuit breaker). My sockets have "10A" stamped on each outlet, even for dual outlets.

Of course a plug-in power board would be limited to 10A in total (for all four sockets) because it's plugged in to a single outlet.

timmmay

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#2278762 18-Jul-2019 10:36

If the sockets are completely independent and either has independent or 20A capacity feed to the switchboard having 10A draw from each should be fine. It's just what things are rated at and how they've been wired in.

Kickinbac

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#2278770 18-Jul-2019 10:54

The fuse/mcb is to protect the cable, not the socket or the appliance plugged in.

With older houses, plug in circuit breakers or fuse wire in ceramic fuses may have been incorrectly uprated.

Best to get an electrician to inspect the circuit and advise.

mclean

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#2279077 18-Jul-2019 14:50

irongarment: That makes no sense. The outlets are rated at 10A each. If I run a wire from the fuse board to a single outlet then I can draw up to 10A, fine. If I continue that wire to another single outlet I can draw 10A from that one too. If both outlets are together in the same box then it's still 10A each. Of course the limiting factor is the circuit breaker, which is 16A, so I could try drawing 10A from each socket on a double outlet, but the breaker would trip.

Also, since nobody knows this magic rule that it's '10A total for a double outlet' [citation needed], and that some outlets are 'better quality than others' (no, they ALL meet the same standard) then it's not unreasonable to believe that people would expect to be able to draw 10A from each socket (limited only by the circuit breaker)....

The standard is pretty clear, but if you prefer to be guided by your expectations then go for it.

irongarment

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#2279101 18-Jul-2019 15:37

mclean:
irongarment: That makes no sense. The outlets are rated at 10A each. If I run a wire from the fuse board to a single outlet then I can draw up to 10A, fine. If I continue that wire to another single outlet I can draw 10A from that one too. If both outlets are together in the same box then it's still 10A each. Of course the limiting factor is the circuit breaker, which is 16A, so I could try drawing 10A from each socket on a double outlet, but the breaker would trip.

Also, since nobody knows this magic rule that it's '10A total for a double outlet' [citation needed], and that some outlets are 'better quality than others' (no, they ALL meet the same standard) then it's not unreasonable to believe that people would expect to be able to draw 10A from each socket (limited only by the circuit breaker)....

The standard is pretty clear, but if you prefer to be guided by your expectations then go for it.

You wouldn't happen to have a link to this 'standard', would you? I don't think anyone knows that two wall sockets together have a 10A combined limit (especially when each one is clearly marked 10A), but a single wall outlet has a total limit of 10A by itself.

MadEngineer

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#2279105 18-Jul-2019 15:45

irongarment:
mclean:
Delphinus: I guess it all depends on the power point. I had some installed in the garage and was advised 10A on each plug (so 20A across them both). To be fair they are sitting about 1cm from the mini fusebox which goes back to the main switchboard via a 6mm TPS (I think, it's pretty thick).

True, it does depend on the outlet - some are better quality than others. But it doesn't alter the fact a twin 10A socket outlet is rated at 10A total, NOT 10A per outlet. When it's temperature tested for compliance with the standard it's tested at 10A (plus 10%) through a SINGLE outlet. Same for a quad-outlet.

That makes no sense. The outlets are rated at 10A each. If I run a wire from the fuse board to a single outlet then I can draw up to 10A, fine. If I continue that wire to another single outlet I can draw 10A from that one too. If both outlets are together in the same box then it's still 10A each. Of course the limiting factor is the circuit breaker, which is 16A, so I could try drawing 10A from each socket on a double outlet, but the breaker would trip.

Also, since nobody knows this magic rule that it's '10A total for a double outlet' [citation needed], and that some outlets are 'better quality than others' (no, they ALL meet the same standard) then it's not unreasonable to believe that people would expect to be able to draw 10A from each socket (limited only by the circuit breaker). My sockets have "10A" stamped on each outlet, even for dual outlets.

Of course a plug-in power board would be limited to 10A in total (for all four sockets) because it's plugged in to a single outlet.

That’s not how it works. The sockets have one cable connecting to one point on the back of of the outlet which is rated for 10A.

For your outlets that show 10A on each socket it’s not 10A+10A, rather 10A max. You’ll be familiar with USB chargers that are labelled similarly

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