I am renovating my house in the Philippines and would like to rewire or wire portions of the house with 110v so I can use the appliances and tools that I bring with me from Canada. The power voltage in the Philippiines is 220v. I would like to install a sub-panel for my 110v distribution. Do I still need a transformer to convert the line from the existing 220 V Panel Board into the new Sub-Panel? If so, where can I get a step-down transformer for my sub-Panel?

Cal,

Hold on, please. It's not just the voltage you need to know.

You need to know the required "Hertz" (Used to be called Cycles) of the equipment.

For example, the U.S. and Canada use 60 Hz. If the Philippines uses 50 Hz, then you also have to convert the 50 to 60 HZ.

Amperage is another concern. You must able to deliver the correct level of amperage for your equipment.

Yes, you will need a transformer 220 volt to 120.

Philippines uses 60 hertz, so there is no issue with that.

http://www.veco.com.ph/index.html

You should be able to find the proper transformer at an electrical distributor.

You may be better finding an electrician that understands local codes, as I not sure if they allow one leg of 120 volts to be grounded as a neutral.

Hi TK and Don,
Thank you for your answers. Sure helps me a lot. My house is located in Northern and I'd like to buy the transformer in Canada or USA before I go back. Where would I be able to order the transformer? Any suggestion? What would be the minimum wattage of the transformer that you would advise me to buy?

Transformers, even small ones, are very heavy. Paying the freight on the weight may be expensive, as transformers are nothing but a solid block of steel and copper.

The size transformer will depend on the amount of power needed at 110 volts.

Since according to the power utility the voltage in the Philippines is 220 volts, and 220 volts is not a standard voltage in North America, a 220 volt to 110 volt transformer would be a special order if one can be found.


I attached a page from a popular American manufacturer. It will show the sizes and weights of a simple single phase unit.

To size a unit, need to know how much load, in amps or wattage.

At 110 volts if you needed say 30 amps, you need a unit rated at least 3300 watts, or VA. The smallest unit ACME has is 7.5 KVA and it weighs 100 pounds.

There is a fair amount of detail I did not get into.

How much load will you have? Need this to size the unit.

I am still of the opinion of buying the proper size and voltage unit you need once you get there.

Thanks again tk!
I planned to only sub-wire the house with 110v for using computers, kitchen & bathrooms appliances, carpentry tools such as Drills, Bench & Skill Saws,compressors, etc. I wonder if 7.5 kva or 10kva would be ample for my needs

I have to wonder also, you have quite a list of devices and appliances, and I do not know what the wattage of each might be, and how many you may need to operate at one time.

A transformer is not all that would be needed. A breaker panel will be needed for how ever many circuits will be needed. I am not sure if the Philippine code requires one leg of the 220 volt to be grounded, if so, and even if not, I would recommend that one leg of your 120 volts be grounded.

This is not as simple as you may think. There are loads, overcurrent protection, short circuit protection, and grounding to be considered.

I fully understand what are the additional needs. I planned to install a sub-panel for the 110v line. As far as the devices and appliances, I would imagine that I would not be using all the devices at the same time.