Working out the safe load for an extension strip

Tezcatlipoca · 12-01-2014, 16:40

If you have multiple devices that you want to plug into a 4 or 6 socket extension strip, how do you calculate if the load is safe or not?

Do you add up the wattage of each device, and see if it is less than the maximum load (13A x 240V [or is it 230V?] = 3120W [or 2990W])?

Or do you add up the amps used by each device and ensure it's less than 13?

Or... either?

What if...

You have three devices, one that uses 100W and the other two use 200W each. Totalled that comes to 500W, so is fine if doing it that way.

But... say the power supply for the 100W device says "input 2.5A" and the power supplies for the other two devices each say "input 5A"... Totalled that comes to 12.5A, which I would assume is too close to the max.

Or am I looking at this wrong?

Tezcatlipoca · 12-01-2014, 17:03

Thanks

So, just to clarify: If I want to add up the amps, I should calculate it from the watts and not just simply take the number of amps stated on the power supply?

Tezcatlipoca · 12-01-2014, 17:54

Thanks

It's stuff like games consoles, an AV receiver, router, etc. Lounge electronics.

qasdfdsaq · 12-01-2014, 18:23

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Stephen · 12-01-2014, 20:52

I don't I just plug everything in lol.

Graham M · 13-01-2014, 11:05

The idea is that the fuse will blow on a 13A strip well before a dangerous situation should be allowed to occur.

raging bull · 13-01-2014, 18:40

A typical extension lead there is a 13 amp fuse, this is sized to suit the cable used.
(So wire is 2.5mm cable which can carry 3Kw load/12amps)
The fuse is there to protect the cable used in the lead, so be aware that it's not suitable to use a 13amp fuse in a cable designed to carry only 10amps/2.5Kw maximum.
Likewise fuses within each device plugged into the extension are protecting each device.
The rating of a fuse marked is the maximum current that the fuse will carry, tables are used to define at what any particular fuse will blow when loaded up.
[Plug fuses are manufactured to BS1362]