wiring question?

N9eav

I have a row of fused switches in the kitchen. 2 are undercounter lights. They are all fed from the 13 amp socket ring, but the switches are fitted with lower amp fuses for lighting purposes.
Now I have a spare one as I never put in a gas hob, so no ignition conection.

The wire coming out is only 1mm lighting cable with twin and earth.

Can I connect this to a 13amp 1kva transformer?

What I intend to do it have the 240 come out of that fused switch under the cabinet into a 1kva transformer, then 110v come out of that into an american socket mounted on the wall. All a bit unusualy but I think everything will be fine except the lighting cable? This will not be comntinuous use, but turned on rarely to power an american appliance.

I know it may not pass the codes, but will my house catch fire?

espresso

Can I connect this to a 13amp 1kva transformer?

I assume what you mean is a 1kva transformer with a 13 amp plug fitted because 1kva is 1000 Volt x Amp i.e. 1000/240 = 4 amps which 1mm twin and earth can easily supply.

beefster

The transformer should have info with it advising on the correct sized fuse to protect it. This should be placed in the switch fuse outlet. This rating will be the maximum fault current and therefore the cable to the xformer should be rated above this.
Note.
If a cable is enclosed in plaster etc the rating is lower as the heat can not escape.

http://www.diydata.com/materials/electric_cable/electric_cable.htm
gives further info.

espresso

beefster wrote:

The transformer should have info with it advising on the correct sized fuse to protect it. This should be placed in the switch fuse outlet. This rating will be the maximum fault current and therefore the cable to the xformer should be rated above this.
Note.
If a cable is enclosed in plaster etc the rating is lower as the heat can not escape.

http://www.diydata.com/materials/electric_cable/electric_cable.htm
gives further info.

Agreed but 1mm cable is rated at 14A or 3.25Kw so even if you halved these figures, it can easily supply kW.

Hope the OP hasn't electrocuted himself :eek:

:rolleyes:

N9eav

espresso wrote:

Can I connect this to a 13amp 1kva transformer?

I assume what you mean is a 1kva transformer with a 13 amp plug fitted because 1kva is 1000 Volt x Amp i.e. 1000/240 = 4 amps which 1mm twin and earth can easily supply.

Thanks, sorry been working. Yep, it's a 1kva builders transformer with 13 amp plug. The 1mm cable is mostly in the wall. The max output is likely to draw only 300w x 110v.

Moss5

This was my post to "110V Issues" thread: -

If you look at the power label on the appliance, it may say 110V @ 60Hz
The output from your transformer will be 110V at nomal (for UK) 50Hz.
Most electric motors are dedicated 50Hz or 60Hz.
If you are lucky, there may be a DC motor with internal rectification.

Hunnymonster

Yes if it's a synchrous motor - the net effect will be that it will run 17% slower (the original ungeared motor speed will be 3000rpm instead of 3600prm), and probably with slightly less power - I don't think that whipping merengue is a power critical task though (or is it ? lol)

Moss5

I have tried running 60Hz refrigerator compressors on a 50Hz supply. They draw high current and cause the 'clixon' overload protector to go open-circuit within seconds.
Without the protector, they would overheat and fail.
If this mixing machine were mine, I would make a temporary connection to prove that the motor can cope (under load) with 50Hz supply.

N9eav

It's getting very techinal. The mixer was free for one thing. It sems to work OK, and if it does burn up, well it does not matter in this case. It may get used, once a week for no more than 5 - 10 minutes. So I don't think it will suffer too badly. I know from my time in Africa that the Americans were running their 110v stuff on transformed 240v and there did not seem to be a problem and that included saws, carpentary tools, mixers, etc.
All I want to make sure is, I don't burn the house down!

Pink.

Hi

Just a quick reminder of the warning at the top of this board.

Announcement: Warning! Always use a professional for gas maintenance and complex electrical repairs. Being safe is more important than MoneySaving.

Pink

espresso

N9eav wrote:

It's getting very techinal. The mixer was free for one thing. It sems to work OK, and if it does burn up, well it does not matter in this case. It may get used, once a week for no more than 5 - 10 minutes. So I don't think it will suffer too badly. I know from my time in Africa that the Americans were running their 110v stuff on transformed 240v and there did not seem to be a problem and that included saws, carpentary tools, mixers, etc.
All I want to make sure is, I don't burn the house down!

Why should it burn your house down?

Just plug your isolation transformer into an existing 13A socket and try using your mixer to see if it works! :rolleyes:

The isolation transformer is a safety device and the fuse in it's plug is there for protection. :cool:

Pink-winged

I think that the warning is a bit OTT, as the poster is simply plugging in an isolation transformer which steps down the voltage to 110V.


:eek: