Question about amps/watts 220v vs 120v

[jackfiasco]

Hi. I have a switch that is rated 10a 220v. I am using it with 120v 500 watt work lights though and would like to know how many it can handle. Do I go by the 10a rating meaning 2 lights (1000 watts / 120 = 8.333 amps)?

Or since it is rated 10a x 220 which equals 2200 watts could I use it for say, 4 lights, totaling 2000 watts?

Thanks in advance!
Jack

 

[rbalewski]

The 10A 220V ratings are maximums. You can put up to 10 amps thru the switch no matter the voltage, and it'll switch up to 220v no matter the current. So in other words, no, you can't double the current rating by halving the switched voltage.

Ron

 

[JD]

SOMETIMES switch manufacturers will list a higher current at a lower voltage. Sometimes they will list a different set of specs for DC vs AC operation. There is no formula for this so check with the manufacturer if it is not stamped on the switch. Manufacturers look at arc potential and wear to come up with these numbers. The trend has been towards not doing this any more, and simply giving one number. Depends on the type of switch. (I am guessing not a US based wall switch.)
In any case, there are a couple of liability issues. Lets say there was a fire and they investigated the switch:
1) Was it the correct application for this type of switch?
2) Was it installed correctly by someone who was approved to do it?
3) Did the switch have more of a load on it then the manufacture rated it for?
4) Did the part have an electrical certification? (UL, etc...)

and next, regulations required for the proper tying of a shoelace...