Load Calculation Backup Generator

Nursery school ;-)

...Jim Thompson

It might seem strange to you but it happened when a farmer bought a surplus generator, hooked it up to his 200 HP tractor, and fired it up. I don't know if it was a 30 amp service or a 100 amp service, but it certainly made an impressive fireworks display when the transformer exploded, showering everything around with burning oil.

Well, it is your story and I guess you are stuck with it, but is sounds like a non sequitur to the topic to me. This thread started out with a question about an 8KW backup generator. I doubt if there are many pole pigs that would have trouble with 8KW, but even then it should blow a properly-sized primary fuse rather than blow the transformer. I won't say it never happened, but it would be a shame if someone got a false impression of danger from your post.

Regards Vaughn

Not if it's designed properly. The small amount ow power available won't "power the whole street" and it will disconnect from the line. Do you think a utility would allow them to be set up to sell power without the proper safeguards?

Those explosions aren't the transformers exploding. It's the fuses. They actually have explosive charges in their mongo fuses to literally blow out the arc when there's a fault and the fuse is trying to open. This is at hundreds, maybe thousands, of amps, and thousands, maybe tens of thousands, of volts.

Cheers! Rich

You haven't been in the Electrical Utility Biz, or you would know that most Pole Pigs are in the 20 to 100 Kw range. Very few of the Home Style Gensets are capable of producing power at that Power Level......

All of the controllers designed to do this synchronize the output to the frequency of the grid. If synchronization is lost the controllers output ceases in less than one cycle.

Pasted from Wikipedia:

In order to prove that AC electricity was dangerous and therefore better for executions, Brown and Edison, who promoted DC electricity, publicly killed many animals with AC, including a circus elephant. They held executions of animals for the press in order to ensure that AC current was associated with electrocution. It was at these events that the term "electrocution" was coined. Edison introduced the verb "to westinghouse" for denoting the art of executing persons with AC current. Most of their experiments were conducted at Edison's West Orange, New Jersey, laboratory in 1888.

and from:

George Westinghouse and Edison became adversaries due to Edison's promotion of direct current (DC) for electric power distribution over the more easily transmitted alternating current (AC) system developed by Nikola Tesla and sold by Westinghouse. Unlike DC, AC could be stepped up to very high voltages with inexpensive transformers, sent over thinner wires, and stepped down again at the destination for distribution to users. Despite Edison's contempt for capital punishment, the war against AC led Edison to become involved in the development and promotion of the electric chair as a demonstration of AC's greater lethal potential versus the "safer" DC. Edison went on to carry out a brief but intense campaign to ban the use of AC or limit the allowable voltage for safety purposes. As part of this campaign, Edison publicly electrocuted dogs, cats, and in one case, an elephant[3] to demonstrate the dangers of AC. Widespread use of DC ultimately lost favor, however, continuing primarily in long-distance high-voltage direct current (HVDC) transmission systems.

So, you're trying to tell us that your pole pig is in the 10 MVA range? Just how big IS that pole?

That's a good plan, that'll set my mind at rest for now :)

Mike.

I did say "tries to ..."

I would hope not. However, we're back to the person with the generator with

13A plug (live) fitted on the end ... you would hope the utility wouldn't allow that either, but people do retrofit stupid things onto existing good systems, and they can go undetected for quite a while!