Discussion in 'Businesses - Services - Products' started by charlyB, Sep 9, 2017.
What did that cost you?
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.
I'm curious how a transformer helps? Is it because it's dedicated? Is it a higher quality? Is it because you put such a small load on the transformer as its only load? It seems that if the distribution line fluctuated so would the output side of the transformer.
I assume similar to a UPS (Uninterrupted Power Supply) it regulates a steady supply of electricity at the output, I am no Professor, I only understand the basics, if it works then that is GOOOOD!
(Thankfully Google is my friend!)
How do electricity transformers work?
those that carry high power drop service. Refuse to buy them. Paid for the concrete post at the back 10 years ago but now the house is built I need more power.
The post needs to come from the Road which has high power, then Noreco would put the post up to our house to carry the drop service.
At the moment 5 bamboo poles hold up the lines lol
Edit, not 50,00 but 350,000 pesoa for the poles
Do you have a certificate of occupancy? In my experience, they drop a lower amp service during the construction phase, but once you get the certificate of occupancy they come back with a higher amp service and a permanent connection. Mine was just hanging loosely hanging across the road until the permanent connection was made. "Knock on wood" trucks don't go through the subdivision much.
The link doesn't really explain why having your own transformer provides better power. My guess is it has something to do with load. P=I x E. P=power, I=Amps, E=voltage. Assuming no loss to make the math easier, what goes into the transformer must go out of the transformer, so 44,000 V x 1 A = 220 V x 200 A. My guess is if you try to draw more than 100 A, the voltage will drop to because you can't create power out of thin air. If every house gets 50A service, then this drop will support 4 houses. Since every house is not likely to be using 50A at the same time, maybe they put 6 or 8 houses on the transformer. Thin provisioning the power, so to speak. I can see two possibilities that might cause an issue. Assuming service isn't controlled/regulated at the line, then the circuit breaker in my house acts as the limiting factor. Now let's say Joe has an electrician buddy who comes in and swaps his circuit beakers from 50A to 75A. In this case, the consumer is causing the issue. The other way this happens is if a new house is built and the power company instead of installing a more powerfull transformer just connects the new service and crosses it's fingers that they don't all turn on their air conditions, fans and electric ovens at the same time. Now looking at the supply side. If the power drops from 44,000 V to 4o,ooo V. The equation becomes 40,000 x 1 A = 220 V x 181.8 A, so a 10% variation on the supply side voltage results in a about a 9% reduction in demand side available current. If these transformers are just barely hanging in there. We start to see problems with the voltage. If I'm only capable of 50 A service, but have a 200 A supply, than the the flectuations on the supply side won't affect me unless it drops to less than 11,000 V. 11,000 V x 1 A = 220 V x 50 A. My guess is there is way to much thin provisioning going on or the home owners are drawing way more power than the electric company sizes for. This really should be easy. I pay for a certain service level and I should be provided that level. That would likely mean oversizing the transformers to insure that fluctuations on the supply side don't cause issues on the demand side. Now maybe someone who actually knows how power systems are sized can straighten me out. I find this interesting.
Edit: The other thing that just came to mind is the stealing of power. In an expat subdivision, it's seems like it would not be much of an issue, but in a squatter area, I can see it being a real problem. It seems like an option to not be thin provisioned for a fair fee might be an interesting option to offer customers, so they don't have to buy their own transformer.
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.
Sounds like a sizing issue. Why not 15-25, instead of 20-30?
I'm guessing at this but I think as time has gone by more people now have a ref, a rice cooker and maybe a TV. Fires to cook are getting less and less (Yippie). The loading of the transformers has slowly crept up. I think if you go back not too many years you would find many customers had nothing more than 1 or 2 light bulbs.