How To Expand Household Power Access? - Page 1
Forum section: electronics / beginners

author: electromateria
author_rank: Regular Contributor
timestamp: July 01, 2022, 06:01:53 am
content: My power company is sending 100 amps to the meter at my house, that's not nearly enough.. I need around twice that since I'm building a shop that will draw tons of power. Can someone please aware me what the process is? Do I need to call the city to get a second 100 amp meter? Do I need to call the hydro company?

author: m k
author_rank: Super Contributor
timestamp: July 01, 2022, 09:28:31 am
content: First you call the power company and ask how thick the incoming cable is and what it can deliver.

author: wizard69
author_rank: Super Contributor
timestamp: July 01, 2022, 05:24:39 pm
content: Quote from: electromateria on July 01, 2022, 06:01:53 amFirst; generally shop equipment is not ran all at once, so how much power you need may not be what you think.Second; your power company and an electrical contractor would work together to get the right installation. Depending upon your positioning of buildings; the electrician might have to do some calculating to get the right feeders sizes.Third; put in an electrical panel box bigger than you may think you need and maybe even what the electrician thinks. You don't really know what you will be doing in the future and simply having free panel slots can make future changes far easier to accomplish. So before approving the upgrade make sure your panel box will have free breaker slots after all work is done.Fourth; don't be surprised if you need more than a panel box, the lateral, meter socket and other things may need replacement. You may very well have to by a considerable amount of equipment and pay for significant installation time.If you have a 100 amp service I'm fairly certain it will need an upgrade. However like I mentioned shops seldom have every machine running at the same time so the actual power you may use at any one time may be lower than you are figuring. What you really want is several independent circuits feeding that shop. Lighting should be on its own circuit(s), for general purpose outlets you will want at least two circuits and possibly many more depending upon how big the shop is. You will also need some number of 240 volt circuits dedicated to things like compressors, table saws, welders or what ever your shop is focused on. Effectively you would want at least 10 breaker slots for even a small shop and you really want to have spares after the initial installation. To put it another way you don't want a shop serviced by one breaker!!!!! The actual number of circuits depends upon the shop and its focus.

author: TimFox
author_rank: Super Contributor
timestamp: July 01, 2022, 05:27:58 pm
content: Just to clarify your situation: the power company does not "send 100 A" to your property.Instead, the wires, meter, breaker box, etc. are all rated for 100 A service.If you need to draw more than that from the utility, you need to see which of the above need to be replaced with higher-rated units.Some of that is property of the utility, and some of that is your property.When last I did something similar, the contractor and the utility co-ordinated the changes.

author: CaptDon
author_rank: Super Contributor
timestamp: July 02, 2022, 01:08:40 pm
content: The power utility may also decide to increase the size of the transformer serving your establishment because it probably also serves some of your neighbors. Sadly those pole transformers (at least most I have seen in service) don't have temperature protection or over-pressure protection and when they get over stressed will sometimes develop a 'single turn short' which won't blow the high voltage feeder fuse but will in fact cause the transformer to explode like a bomb, sometimes shearing off the part of the pole where it is mounted. One of my co-workers had flaming oil and pieces of a pole mounted transformer come through his second floor living room window and start a fire. Good he was home and put the fire out himself. He said the explosion was so loud it sounded like a shotgun was fired in the living room!!

author: wizard69
author_rank: Super Contributor
timestamp: July 03, 2022, 06:32:51 pm
content: Tim has some good points that I maybe didn't express well in my reply. Hopefully by responding to this post I can help people that don't understand AC systems.Quote from: TimFox on July 01, 2022, 05:27:58 pmThe power company has the availability of or the possibility of sending 100 amps to your property. How much can actually be sent is a bigger question, especially if the transformer is shared by several homes.QuoteThis is an important concept, it is the incoming switch gear that determines how much power your home can pull from the grid safely. The main breaker is what protects your switch gear from excessive draw.QuoteOften the answer is all with these small capacity services. I currently live in a house where the original panel box had 4 breakers which is an extreme case of being under configured for a modern household. 100 amps use to be a reasonable number until the advent of all the "mandatory" goodies such as air conditioning, electric ranges, electric dryers, electric water heaters and whatever else. Now a 100 amp service is questionable size wise.QuoteI'm almost 100% certain that at this point in time the services of a contractor will be required. He will be able to interface with the power company and will be able to determine if feeder sizing will need to be done to support large loads or a sub panel.However the home owner here does not need to rely upon the contractor to do everything and could in fact save a lot of money by installing much him self. The easiest way to take this one is to find a local tech school offering courses on DIY home electrical work. A properly run course can get a home owner up to speed fairly quickly to handle the electrical outlets and lighting circuits. Further he will be keyed in on local code requirements. I really believe that DIY here is a possibility as long as the person doing it takes the time to learn the proper methods and practices and is also willing to find a contractor that will take on the heavy work.As an aside, which maybe will help some home owners with understanding current versus voltage, my father built a garage when I as very young that was well detached from the house. As usual money was tight and thus the feeder for the garage was not implemented for some time. So we ran the garage off an outlet at the side of the house with a long extension cord. If you started up the table saw at nights the lights would dim and eventually the saw would come up to speed if you didn't pop the breaker. You could actually vary light intensity by how hard you shoved wood through the saw. In any event learned a bit from that about current draw, voltage drop and what a lack of money can do for a project. Now my father knew what was going on and frankly I was just learning about electricity and electronics, so a few years latter the garage got a proper feeder. I remember this because I was the one that got to dig the trench and help my brother pull the wire. I also remember my father going over the NEC to figure the proper feeder sizing (well in retrospect I think that is what he was doing), remember just a kid far from his teens then.In any event the point here is that if you have a shop the current requirements vary depending upon what you are doing. You could run a shop on a 20 amp circuit but believe me you will not like the result. The amount of power a shop requires will vary a lot depending upon how much can realistically be run at the same time. Voltage should stay constant in a shop, current demand varies depending upon the loads presented to the power supply. One minute a shop could be drawing 7 amps the next minute 70 amps (say a compressor and welder running at the same time along with the usual lighting loads.) This is where realistic planning needs to take place before even talking to a contractor. In the end the contractor can only do a good job if he knows what will be happening in that shop.I hope this helps homeowners that don't feel like the understand electricity well. Often they feel like the contractor is trying to rip them off. In most cases I don't believe this is the issue, contractors unfortunately are legally liable for their work even if it conflicts with homeowner desires.

author: jmelson
author_rank: Super Contributor
timestamp: July 03, 2022, 06:41:23 pm
content: Quote from: CaptDon on July 02, 2022, 01:08:40 pmWhen the transformer exploded, it almost certainly blew the high voltage fuse. These have a piece of "det-a-cord" in the ceramic fuse case to assure the arc is blown out. They definitely DO sound like shotguns being fired.Jon

author: CaptDon
author_rank: Super Contributor
timestamp: July 04, 2022, 01:39:46 am
content: I am probably sure after the transformer ruptured explosively and the boiling oil took flame it probably did take out the high voltage fuse. But pondering if during the explosion the high voltage input lead was blown clear perhaps the fuse survived? Pieces of the ruptured case and flaming oil came through his window. The transformer was on a pole located across the sidewalk (10-12 feet?) from the second floor window. I had been at the house many times. We used to watch 'Saturday Night Live' in the second floor living room (back in the Chevy Chase years). Guessing the transformer could have been 30 years old even back then!! Most probably filled with 500Kppm PCB fluid called Inerteen.