Utilities & Mobile Best Posts in Thread: Noreco

I can't comment on all of the Philippines just what I see in my neighborhood.
I don't have a real answer on what is the biggest issue but I do have a gut feel. Overloaded transformer and small diameter wiring cause a lot of problems. Overloaded transformers or lengthy wires feeding 220 volts to the house cause low voltage.
Induction motors for pumps and refrigerators can burn out from under-voltage.
Electronics for televisions and computers usually have a switching type power supply which will tolerate a wide range of input voltages (90-265 volts).

 

Why would you want your own transformer and why is that better?
I'll try and explain.
If you look at the electrical system as a whole. The power is generated at 13.8 Kv then boosted up to 69 Kv and sent to the substations. At the substation the voltage is reduced to 7 Kv and distributed around the city.
Noreco has small transformers all over the city that reduce the 7 Kv down to 220 volts. There may be 20 or 30 homes on each of those transformers.
Picture this: if all of your neighbors turn on their aircons or rice cookers the voltage will drop at your house because of the increased load. The pole mounted transformers typically have a voltage drop of about 10% at full load (more if overloaded). Low voltage really kills motors such as aircons and refs. If one of your neighbors is using something like an arc welder your voltage will be all over the map.
At the power generation station the voltage of the 13.8 Kv/69 Kv/7 Kv systems are regulated to the correct levels. If your home is feed from a transformer connected to the 7 Kv system then your voltage will be fairly stable as the voltage will only be effected by your household load.
Noreco can adjust their power generation based on what happens throughout the island but they can not control what happens in your neighborhood.
If you have expensive electrical/electronics and some spare cash then buy a transformer.

 

If you have your own transformer that is not tapped off of other folks then you should have fairly solid voltage. Another thing that folks seem to forget is a properly grounded system; you get 220-240 from your pole mounted transformer...you need your neutral and ground (grounding and grounded conductors) purposely "bonded" together at your main panel with a ground rod.

Surges on your electrical system in this scenario are minimized. I can get into more detail if needed on other options for additional surge arresting.

My wife did away with cable TV so our internet comes in on a single pair of what is basically telephone wire...I have not had any issues with lightning but it could be an issue and personally should install a lightning arrestor to be safe but have not gotten around to it yet (very cheap...but have not looked at sourcing them in the PI).

We've had no issues with voltage drop, surges or anything short of geckos messing up any electronics.

Shawn

 

15 KVA is the rating of the transformer. 15 KVA means 15,000 Volt x Amps.
So 15,000VA/220 volts = 68 Amps. The rated current from your transformer is 68 amps.

A typical motor draws about 4.25 Amps per horsepower. You could theoretically run about 16 horsepower worth of air-conditioning or who knows how many rice cookers.

15 KVA is certainly a good sized transformer for a single house.
The main advantage to running a large transformer is; If you used the whole 15 KVA the voltage would drop about 22 volts (10%).
If you are only using 7.5 KVA out of 15 KVA, the voltage will only drop 11 volts (or (7.5 KVA/15KVA)*10%).

 

I guess I don't understand why the distributor isn't on the hook for infrastructure that they own. If you had cable TV and the picture was pixelating due to poor single strength from the drop owned by the cable company, would you go and buy a new drop for the cable company so that you get a good picture? It's not a perfect analogy, but it's pretty close. Why is power looked at differently than other service providers like cable?

 

Geckos are a problem...2 TVs repaired because of them crawling inside. A good friend had a window shaker AC unit shorted out from a Gecko...fortunately we tore it apart and was able to get it back up and running.

When we built our house I was also surprised that we had to get our own transformer...as you would think that would be a responsibility of the local utility company. Nope, and money well spent as we are rocking 240 and no issues that other folks have.

I've posted many replies when it comes to secondary voltages and the issues folks are unfortunately having. I'm more than happy to answer any questions/concerns.

Shawn

 

The 2x Desktop PC's failed during Brownouts, when the power came back on, they did not. Before that though; 1x (Antec 650W) Power Supply went up in smoke fritzing away during normal use, 1x Monitor went up in smoke before my eyes during normal use, then, when 1x Monitor failed to turn on, the wife said she could smell a burning smell (my sense of smell is not so good) but I couldn't smell a thing, but it no longer worked.

The Laptop was damaged during a Storm, I hopped up and turned everything off when I noticed lightning in the distance, and although I am 99% sure I unplugged the Laptop at the same time as the TV and Fridge and Freezer, it *may* have been still plugged into my AU Power-board. At around 1am; I swear the world's loudest clap of thunder woke the dead here! The next morning the Laptop was also dead, but the strange part of that experience was the Modem and Pay TV Box were also fried. The last 2 were not even plugged in (DEFINITELY UNPLUGGED) so in my thinking the lightning must have come in through the ADSL Cable as it is the only way power could have reached both the Modem and TV Box which were unplugged from power, and in part, I suspect maybe because the Modem was connected to the Laptop via the LAN Cable, maybe it caught a jolt also?

 

VA (Voltampere) is the term about how much power an electrical circuit unit can provide. 1 VA is similar to 1 W (Watt). This means if a transformer have 15 kVA then it can provide at most power up to 15 kW power. Effectively the load you can really connect to a such transformer is about 10% to 20% lower because of the blind load. In the Philippines better calculate with 20% because the appliances have not the quality and efficiency of US and European appliances.

 

I bought a used 25kv transformer from Polaris 7 years ago, I think I paid 55,000p. Noreco installed it. A storm knocked it out once and Noreco came out and reset it.