Help needed regarding powering an Electric Iron on different voltage!

[sarthakmsinghal]

Hi everyone,
I recently bought my electric cloth iron (Panasonic) which I used in the US (110V) to India (220V), 1500W. I was thinking of how I could get it to work, and only reasonable solution I could come up with was to use a diode on the live wire to provide 110V RMS voltage and hence same power. Can you please tell me if this will work without many issues?

Another thing, my mom powered it without telling me and luckily nothing blew up and the iron didn't work either. Anyone know what the problem might be?

Thanks a lot

 

[barry]

As far as I know, India has totally different electrical outlets from the US, so there's no way you could plug a US plug into an Indian socket. Unless you changed the plug on the iron...

If you put 220 volts across a heater(iron) intended for 110, you could conceivable burn out the heater, as you would generate four times as much power.

 

[sarthakmsinghal]

As far as I know, India has totally different electrical outlets from the US, so there's no way you could plug a US plug into an Indian socket. Unless you changed the plug on the iron...

If you put 220 volts across a heater(iron) intended for 110, you could conceivable burn out the heater, as you would generate four times as much power.

I will be using heavy duty socket converter, so that is a non-issue.

I do realize that it will use 4 times as much power, hence the reason I asked for possible solutions. I cannot use a transformer simply because the 1500W transformer would weigh and cost a ton. That is why I was wondering if the diode solution should work fine, since I don't think there are any electronics other than the heating element and the thermostat.

 

[KlausST]

Hi,

If you use a diode on 220V you get about 150V rms.
Your iron will be powered with 3000W.

... my mom....
Inside the iron there is a temperature regulation. With 200V it gives 4 times the rated power, so it will heat up to the desired temerature in 1/4 of time. Then power is switched off until temperature drops to a certain level an power is switched on again.
This is not healthy for the heater and the temperature switch.

Expect a shorter livetime..


Klaus

 

[sarthakmsinghal]

Thanks for your reply. Although nothing blew up, the iron is not working anymore either (at least not on 220V).
I don't understand how the diode will give 150V. I am guessing your calculation is 220/sqrt(2) but I don't know if that is correct. Please tell me if I am wrong.

 

[deepeshmishra]

you can use an auto-transformer that you can down the voltage according to power

as your load is resistive then a rated power diode also can work since it clips negative peak and voltage will be half

 

[Dan Mills]

Ahh, you may want to rethink that!

Double the input voltage into a resistive load, the power goes up 4 times, now chop half the waveform off, you still end up with twice the power the thing was intended to use......

Somewhat counterintuitively a diode in series does NOT turn 240V RMS into 110V RMS...

Just pick up a local version in India rather the trying to bodge up a 120V supply at 15A (It will be cheaper).

 

[sarthakmsinghal]

@Pick up local version in India-
I know that is the best option and the safest. My family started appealing to my ego (I am studying electrical engineering) that is why I pursued this silly task. Thanks anyways.

 

[dick_freebird]

There has to be a surplus of surplus, you should be able to
find a 220V:110V transformer suitably sized for the load.
Or a center tapped 220V isolation transformer. I paid $6
apiece for three 110V 20A isolation xfmrs at the local
electronics surplus place, for my lab benches (ground
hum is bad in the building, isolating and grounding to
earth is the bench upgrade plan).

India plug on the 220 side, American socket on the 110V
(or half-220V) side, and you've got a general purpose
adaptor. May as well go as big on the transformer as
your wallplug service rating, unless you want it for travel.

 

[barry]

I would just wear wrinkly clothes.

 

[red_alert]

What about using a simple light dimmer (triac based)? Being a non-inductive load, you shouldn't have much problems with EMI.

You could also use a zero-cross triggering technique (using a MOC3083 triac driver and a LM555 timer) to skip some (half) sine waves to get the desired output power.

 

[FvM]

1-out-of-4 full wave switching by a triac circuit would be probably the better way, because halfwave (involving DC current) is unwanted too and banned by power quality standards.

Unfortunately, the low resistance load involves 40 A peak current and will probably cause flicker in weak power supply networks (e.g. at most sites in india).