Dear Joel,
Yes, you can use an American 120 volt breaker & American 120 volt wire on Philippine 220 volt systems. American style 220 volt breakers are actually two 120 volt breakers tied together so they both open in case of an overload or short circuit, American breakers are rated at 300 volts. Even light duty American lamp cord (wire for plug) is rated at 300 volts, they use the same cord in the PI for 220. You will have to check the writing on your "romex" house wire for the voltage rating for the insulation, but I imagine it will be 600 volts. Any breaker has to be the correct style & brand to fit the panel it's installed in and has to be the correct ampere rating for the circuit: 15 amps, 20 amps, etc. And any wire installed on either 120 or 220 must be large enough to carry the amp rating of the breaker or fuse.
Best always,
Harry.
I do have a question about wiring in the phils. When there I notice that the "power boxes" are similar to our boxes here. The one my friend Maki has has breakers that look very similar to ours also. So here's my question.....can you use a 110 breaker on a box there and run a circuit of 110 wire? Or do the boxes there not permit for that? I remember my dad always putting the boxes together on houses he build when I was growing up and would spend a day with him at his company. He could use both 110 and 220 breakers(fuses earlier in my childhood) on the same "spine" of the power box. If such is available there, I can see myself running a couple circuits in the house with maybe a different color plug or something to keep them "separated" in appearance from the normal 220.
Thanks for any help,
Joel P.