1000W on 5amp circuit

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vladfi

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I'm planning on running 1000W from a 5amp circuit (round pin, switched from the wall). At 230V, this should only draw 4.3amps, which is a bit close to the limit. Is there any danger here?

I'm also thinking of putting a 5amp fuse in the plug just to be safe. I'm curious if the fuse orientation matters at all -- I assume not because it's AC, but just wanted to double check.
 
I'm planning on running 1000W from a 5amp circuit (round pin, switched from the wall). At 230V, this should only draw 4.3amps, which is a bit close to the limit. Is there any danger here?

I'm also thinking of putting a 5amp fuse in the plug just to be safe. I'm curious if the fuse orientation matters at all -- I assume not because it's AC, but just wanted to double check.
Unusual to have fused in the plug with 5 amp round pin type.

1000w on a 5 amp circuit should be OK with the possible issue of inrush current, when some loads are switched on they take a much higher current than when theyre running. No danger in giving it a try.

Fuses BTW it doesnt matter which way round they go, they're just a piece of thin wire inside.
 
Reading between the lines this is a 5A lighting circuit and you want to plug a 1kW load into a 5A socket switched from it.

What about the rest of the loads on that circuit?
 
Welcome to the magical mysterious "Electrical-Forumbulator"..

Assuming this is a UK installation..
A 5amp lighting circuit sounds like it could be quite old wiring.... ?
Possibly in need of updating?
(e.g. 5A 3036 Wylex re-wireable -vs- 60898 / 61009 more commonly 6A MCB/RCBO)

Re your 1000watt load...

(a) A 5A fuse/MCB does not trip the instant the load reaches just over 5amps..
There are tolerances to allow for voltage fluctuations, inrush currents, short duration surges.. etc.. etc..

(b) With the majority of lighting and socket circuits diversity is your friend...
Which basically allows for the fact the every possible load on a circuit is not always switched on at the same time for long durations...

(c) A 5amp circuit at a nominal 230v is good for 1150Watts.. so your 1000watt load still has 150watts of spare capacity "Excluding" any Diversity considerations..

(d) A traditional rule-of-thumb diversity consideration for lighting circuits is 66% of total connected loads... So Add up all of the known loads you have connected to this circuit.. Either in 'Amps' or 'Watts'...
Then see how close you are to 66% of 5amps, or 66% of 1150Watts..?

(e) Historically it was not uncommon to find 'one', 'or more', 500watt external halogen floodlights over gardens / front drives etc.. connected to an existing 5A / 6A lighting circuit, with potential extra 500watt and/or 1000watt loads on the circuit with NO operational problems!!!!!!

My gut feeling without seeing your actual installation..
Is I don't think you will have any problems!!?
 
and in many cases, although its fused a 5/6a, its often possible to change the circuit to 10 or sometimes 16 without any more work than changing the breaker. wiring etc would need to be checked to make sure its safe to do so
 
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