How far away is your power transformer?

[Gary D]

I'll have to go and look for ours, I think the feed to our houses is only something like 40A.

[Mike J]

8 hours ago, fototek1 said:

I need to do the calculations but we will need a larger unit. In the US we have 200AMP service and I believe that will equal a 50kva transformer.

200 amp panels are pretty much the standard in the USA.   The 220 amp reflect the capacity of the main breaker in the panel, not how much power you actually require for present and/or future needs.  The following site may help in main panel and breaker sizes.  I say "may help" because you of sort of working backward from what you have to what you need coming into the house.  We ended up having to replacing 100% of the wiring, receptacles, and main panel in one house due to electrical issues and substandard wiring.  The article in written for American readers so the example reflect 120 volts instead of the 240 used here.

https://www.thespruce.com/calculate-electrical-circuit-load-capacity-1152739

The term electrical load capacity refers to the total amount of power provided by the main service for use by your home's branch circuits and the lights, outlets, and appliances connected to them. Understanding capacity and load becomes necessary if you are planning the electrical service for a new home, or if you are considering an electrical service upgrade to an older home. Understanding the load needs will let you choose an electrical service with an appropriate capacity. In older homes, it's extremely common for the existing service to be badly undersized for the needs of all the modern appliances and features now in use.

Total electrical capacity of an electrical service is measured in amperage (amps). In very old homes with knob-and-tube wiring and screw-in fuses, you may find the original electrical service delivers 30 amps. Slightly newer homes (built before 1960) may have 60-amp service. In many homes built after 1960 (or upgraded older homes), 100 amps is the standard service size. But in large, newer homes, 200-amp service is now as a minimum, and at the very top end, you may see 400-amp electrical service installed.

How do you know if your current electrical service is adequate, or how to plan for new electrical service? Determining this requires a little math to compare total available capacity against the likely load that will be placed on that capacity.

elecrtical circuit load capacity
Nusha Ashjaee/The Spruce
Understanding Electrical Capacity
Calculating how much power your home needs is a matter of calculating the amperage load of all the various appliances and fixtures, then building in a margin of safety. Generally, it's recommended that the load never exceed 80 percent of the electrical service's capacity.

To use the math, you need to understand the relationship between watts, volts, and amps. These three common electrical terms have a mathematical relationship that can be expressed in a couple of different ways:

Volts x Amps = Watts
Amps = Watts/ volts

These formulas can be used to calculate the capacity and loads of individual circuits, as well as for the entire electrical service. For example, a 20-amp, 120-volt branch circuit has a total capacity of 2,400 watts (20 amps x 120 volts). Since the standard recommendation is for the load to total no more than 80 percent of the capacity, this means that the 20-amp circuit has a realistic capacity of 1920 watts. So to avoid the danger of overloads, all the light fixtures and plug-in appliances together on this circuit should consume no more than 1,920 watts of power.

It is fairly easy to read the wattage ratings of all the lightbulbs, television sets, and other appliances on the circuit to determine if a circuit is likely to overload. For example, if you routinely plug a 1500-watt space heater into a circuit, and run several light fixtures or lamps with 100-watt bulbs on the same circuit, you have already used up most of the safe 1920-watt capacity.

The same formula can be used to determine the capacity of the house's overall electrical service. Because a home's main service is 240 volts, the math looks like this:

240 volts x 100 amps = 24,000 watts
80 percent of 24,000 watts = 19,200 watts
In other words, a 100-amp electrical service should be expected to provide no more than 19,200 watts of power load at any given time.

Calculating Load
After you know the capacity of individual circuits and of the home's full electrical service, you can then compare this with the load, which you can calculate simply by adding up the wattage ratings of all the various fixtures and appliances that will be drawing power at the same time.

You might think this involves adding up the wattage of all the light fixture lightbulbs, all the plug-in appliances, and all the hard-wired appliances, and then comparing this to the total capacity. But it is rare for all electrical appliances and fixtures to run at the same time—you wouldn't run the furnace and the air conditioner at the same time, for example; nor is it be likely that you would be vacuuming while the toaster is running. For this reason, professional electricians generally have alternative methods for determining the appropriate size for the electrical service. Here is one method that is sometimes used:

Add together the wattage capacity of all general lighting branch circuits.
Add in the wattage rating of all plug-in outlet circuits.
Add in the wattage rating of all permanent appliances (ranges, dryers, water heaters, etc.)
Subtract 10,000.
Multiply this number by .40
Add 10,000.
Look for the full wattage rating of permanent air conditioners, and the wattage rating heating appliances (furnace plus space heaters), then add in whichever is the larger of these two numbers. (You don't heat and cool at the same time, so don't need to add both numbers.)
Divide the total by 240.
This resulting number gives the suggested amperage needed to power the home adequately. You can easily evaluate your current electrical service by using this formula.

Other electricians suggest another simple rule-of-thumb:

100-amp service is generally large enough to power a small- to moderate-sized home's general branch circuits, plus one or two electric appliances, such as a range, water heater, or clothes dryer. This service may be sufficient for a home under 2,500 square feet if the heating appliances run on gas.
200-amp service will handle the same load as 100-amp service, plus electric appliances and electric heating/cooling equipment in homes up to about 3,000 square feet in size.
300- or 400-amp service is recommended for large homes (more than 3,500 square feet) with all-electric appliances and electric heating/cooling equipment. This service size is recommended where the expected electric heat load is over 20,000 watts. A 300- or 400-amp service is usually provided by installing two service panels—one providing 200 amps and a second providing another 100 or 200 amps.
Plan for the Future
It is generally a good idea to oversize an electrical service to make future expansion possible. In the same way that 100-amp service quickly became undersized when electric appliances become common, today's 200-amp service may someday seem badly undersized when you find yourself recharging two or three electric cars. An oversized electrical service will also make it possible to run a sub-panel out to your garage or shed if you someday choose to take up woodworking, welding, pottery or another hobby requiring lots of power.

[Gary D]

27 minutes ago, Mike J said:

200 amp panels are pretty much the standard in the USA.   The 220 amp reflect the capacity of the main breaker in the panel, not how much power you actually require for present and/or future needs.  The following site may help in main panel and breaker sizes.  I say "may help" because you of sort of working backward from what you have to what you need coming into the house.  We ended up having to replacing 100% of the wiring, receptacles, and main panel in one house due to electrical issues and substandard wiring.  The article in written for American readers so the example reflect 120 volts instead of the 240 used here.

https://www.thespruce.com/calculate-electrical-circuit-load-capacity-1152739

The term electrical load capacity refers to the total amount of power provided by the main service for use by your home's branch circuits and the lights, outlets, and appliances connected to them. Understanding capacity and load becomes necessary if you are planning the electrical service for a new home, or if you are considering an electrical service upgrade to an older home. Understanding the load needs will let you choose an electrical service with an appropriate capacity. In older homes, it's extremely common for the existing service to be badly undersized for the needs of all the modern appliances and features now in use.

Total electrical capacity of an electrical service is measured in amperage (amps). In very old homes with knob-and-tube wiring and screw-in fuses, you may find the original electrical service delivers 30 amps. Slightly newer homes (built before 1960) may have 60-amp service. In many homes built after 1960 (or upgraded older homes), 100 amps is the standard service size. But in large, newer homes, 200-amp service is now as a minimum, and at the very top end, you may see 400-amp electrical service installed.

How do you know if your current electrical service is adequate, or how to plan for new electrical service? Determining this requires a little math to compare total available capacity against the likely load that will be placed on that capacity.

elecrtical circuit load capacity
Nusha Ashjaee/The Spruce
Understanding Electrical Capacity
Calculating how much power your home needs is a matter of calculating the amperage load of all the various appliances and fixtures, then building in a margin of safety. Generally, it's recommended that the load never exceed 80 percent of the electrical service's capacity.

To use the math, you need to understand the relationship between watts, volts, and amps. These three common electrical terms have a mathematical relationship that can be expressed in a couple of different ways:

Volts x Amps = Watts
Amps = Watts/ volts

These formulas can be used to calculate the capacity and loads of individual circuits, as well as for the entire electrical service. For example, a 20-amp, 120-volt branch circuit has a total capacity of 2,400 watts (20 amps x 120 volts). Since the standard recommendation is for the load to total no more than 80 percent of the capacity, this means that the 20-amp circuit has a realistic capacity of 1920 watts. So to avoid the danger of overloads, all the light fixtures and plug-in appliances together on this circuit should consume no more than 1,920 watts of power.

It is fairly easy to read the wattage ratings of all the lightbulbs, television sets, and other appliances on the circuit to determine if a circuit is likely to overload. For example, if you routinely plug a 1500-watt space heater into a circuit, and run several light fixtures or lamps with 100-watt bulbs on the same circuit, you have already used up most of the safe 1920-watt capacity.

The same formula can be used to determine the capacity of the house's overall electrical service. Because a home's main service is 240 volts, the math looks like this:

240 volts x 100 amps = 24,000 watts
80 percent of 24,000 watts = 19,200 watts
In other words, a 100-amp electrical service should be expected to provide no more than 19,200 watts of power load at any given time.

Calculating Load
After you know the capacity of individual circuits and of the home's full electrical service, you can then compare this with the load, which you can calculate simply by adding up the wattage ratings of all the various fixtures and appliances that will be drawing power at the same time.

You might think this involves adding up the wattage of all the light fixture lightbulbs, all the plug-in appliances, and all the hard-wired appliances, and then comparing this to the total capacity. But it is rare for all electrical appliances and fixtures to run at the same time—you wouldn't run the furnace and the air conditioner at the same time, for example; nor is it be likely that you would be vacuuming while the toaster is running. For this reason, professional electricians generally have alternative methods for determining the appropriate size for the electrical service. Here is one method that is sometimes used:

Add together the wattage capacity of all general lighting branch circuits.
Add in the wattage rating of all plug-in outlet circuits.
Add in the wattage rating of all permanent appliances (ranges, dryers, water heaters, etc.)
Subtract 10,000.
Multiply this number by .40
Add 10,000.
Look for the full wattage rating of permanent air conditioners, and the wattage rating heating appliances (furnace plus space heaters), then add in whichever is the larger of these two numbers. (You don't heat and cool at the same time, so don't need to add both numbers.)
Divide the total by 240.
This resulting number gives the suggested amperage needed to power the home adequately. You can easily evaluate your current electrical service by using this formula.

Other electricians suggest another simple rule-of-thumb:

100-amp service is generally large enough to power a small- to moderate-sized home's general branch circuits, plus one or two electric appliances, such as a range, water heater, or clothes dryer. This service may be sufficient for a home under 2,500 square feet if the heating appliances run on gas.
200-amp service will handle the same load as 100-amp service, plus electric appliances and electric heating/cooling equipment in homes up to about 3,000 square feet in size.
300- or 400-amp service is recommended for large homes (more than 3,500 square feet) with all-electric appliances and electric heating/cooling equipment. This service size is recommended where the expected electric heat load is over 20,000 watts. A 300- or 400-amp service is usually provided by installing two service panels—one providing 200 amps and a second providing another 100 or 200 amps.
Plan for the Future
It is generally a good idea to oversize an electrical service to make future expansion possible. In the same way that 100-amp service quickly became undersized when electric appliances become common, today's 200-amp service may someday seem badly undersized when you find yourself recharging two or three electric cars. An oversized electrical service will also make it possible to run a sub-panel out to your garage or shed if you someday choose to take up woodworking, welding, pottery or another hobby requiring lots of power.

And then we come to the Philippines where the average house load is a TV, fridge and 3-4 5W light bulbs all supplied by a piece of wet string.

[Mike J]

5 minutes ago, Gary D said:

And then we come to the Philippines where the average house load is a TV, fridge and 3-4 5W light bulbs all supplied by a piece of wet string.

But the string dries out in April or thereabouts.  When the wiring, etc was pulled from the house that we had redone, it was scary as hell!  In my first couple of years here I received more electrical shocks than my entire life living in the USA. 

[Gary D]

1 minute ago, Mike J said:

But the string dries out in April or thereabouts.  When the wiring, etc was pulled from the house that we had redone, it was scary as hell!  In my first couple of years here I received more electrical shocks than my entire life living in the USA. 

I wired our current house plus a bil and two sil with UK wiring, outlets etc but the problem is that one of the bil thinks he is an electrician/plumber/carpenter etc won't stop interfering when we are away and I have to put it back together on my return. When I wired one sil's house she was complaining about getting shocks from metal parts like the switch and outlet fixing screws, someone had cut the earth wire for the copper. She was recently complaining that she was getting shocks from her iron, the earth wire was still there just hanging, someone had stolen the earth stake.

[Tommy T.]

Lots of good ideas from you boys regarding wiring our new house here. No wet string permitted... And a good, solid ground required for all outlets and lights... I will let you know how it goes...

[fototek1]

Excellent information! We need a big transformer :) and now I am seeing that the price is actually not that bad. 

Edited October 13, 2019 by fototek1
spelling

[Tukaram (Tim)]

How far?  Far enough enough away that I have never seen it.  I wonder how many houses our transformer serves?  Probably too many ha ha.  I need to ask around and see if someone knows where it is. There has to be one somewhere...  :)

[fototek1]

I did the calculations and we need a 50KVA. The local power company (Meralco) engineer came out and counted all the light bulbs (hahahaha), looked at the aircon loads, water heater loads and all other electrical appliances and fixtures and said they will have the calculations complete on Monday and will get back to us with the price. The engineer said that we would have to pay up front for the transformer and they would discount our electric bill 70%  for 1-3 years depending on the size of the transformer. They also said that the transformer installed would be bigger than what we need because others building next to us would be connected but they will guarantee  that we will have the supply we need and if we have voltage drops they will fix it. Basically he told me everything I would like to hear but I don't believe it.

[jimeve]

3 hours ago, fototek1 said:

I did the calculations and we need a 50KVA. The local power company (Meralco) engineer came out and counted all the light bulbs (hahahaha), looked at the aircon loads, water heater loads and all other electrical appliances and fixtures and said they will have the calculations complete on Monday and will get back to us with the price. The engineer said that we would have to pay up front for the transformer and they would discount our electric bill 70%  for 1-3 years depending on the size of the transformer. They also said that the transformer installed would be bigger than what we need because others building next to us would be connected but they will guarantee  that we will have the supply we need and if we have voltage drops they will fix it. Basically he told me everything I would like to hear but I don't believe it.

That's huge 50kva, are you going to supply the whole barangay? Ours is only 15Kva and have a 3 story house and a second house.