Generator and electricity flow

[Gale Hawkins]

We all agree a transfer switch is idea but an interlock is better than nothing.

This morning the question popped in my mind is back feeding a grid by accident or intent even possible in the real world more than a micro second with the typical home back up generator used in a hacked fashion in a storm?

We have access to 7KW, 6KW, 3KW and .8 KW generator if needed during a storm. They all have rated circuit breaks that work really really fast when over loaded. Would not a grid load look so HUGE that the generator breaker system trip instantly or kill the engine. If the grid became live from the power company I could see it frying the typical back up generator but it seems to me the breakers would open fast if the generator was seen as a direct short to the grid source.

I really have not experience on this subject but know if I over load any generator that we have access to the breakers pop very fast.

I read the warnings about back feeding dangers but have not found a "confirmed" case of a lineman dying from it but I am sure someone has a confirmed case(s) they can post links concerning such cases.

It seems it is technically impossible for backing feeding to kill a lineman if the lineman is working as directed per lineman codes.

There is no defense for a home owner that would connect a home generator to the power grid period. I am just asking is there a proven case when a lineman died from back feeding where a home generator was the cause. It seems in the legal case linemen are to trip transformers feeding the homes or at least create a dead short of the grid on both sides of where they are doing line repairs.

Pike Electric, Inc., Docket No. 01-0166

Electric Company lineman dies

 

[aczlan]

This morning the question popped in my mind is back feeding a grid by accident or intent even possible in the real world more than a micro second with the typical home back up generator used in a hacked fashion in a storm?
We have access to 7KW, 6KW, 3KW and .8 KW generator if needed during a storm. They all have rated circuit breaks that work really really fast when over loaded. Would not a grid load look so HUGE that the generator breaker system trip instantly or kill the engine. If the grid became live from the power company I could see it frying the typical back up generator but it seems to me the breakers would open fast if the generator was seen as a direct short to the grid source.

If your transformer has a short in it or if you only are connected to a couple of houses (due to lines being down) it is possible that your genset could handle the load of the part fo the grid that it is connected to.

Aaron Z

 

[Gale Hawkins]

If your transformer has a short in it or if you only are connected to a couple of houses (due to lines being down) it is possible that your genset could handle the load of the part fo the grid that it is connected to.

Aaron Z

"If your transformer has a short in it" part of your reply I do not follow.

 

[sdkubota]

Fact is there isn't a lineman worth his pay that doesn't treat every line like it is live at all times. Ones that don't end up dead and it isn't because of home generators. The entire backfeed story is nothing more then a folktale that won't die. Yes, people shouldn't be screwing with power because it is dangerous. I challenge anyone tyo publish a single electrocution event of a linesman attributed to a home generator.
(ducks and runs for cover)

 

[Gale Hawkins]

sdkubota I was taken back when could not find one 'confirmed' lineman death from a home generator. Not sure why I woke this morning with the BS detector going off on this subject. I can not see an 8000 watt generator boosting 120 volts to 7200 volt with ease or amperage.

I think some would be surprise how some linemen power their whole house during a long outage.

 

[BeezFun]

Fact is there isn't a lineman worth his pay that doesn't treat every line like it is live at all times. Ones that don't end up dead and it isn't because of home generators. The entire backfeed story is nothing more then a folktale that won't die. Yes, people shouldn't be screwing with power because it is dangerous. I challenge anyone tyo publish a single electrocution event of a linesman attributed to a home generator.
(ducks and runs for cover)

First hit with google:
Lineman killed by customer generator

 

[sdkubota]

First hit with google:
Lineman killed by customer generator

Propoganda for someone who did not follow their own safety regulations so his family can receive union benefits. Like I said, there isn't a lineman alive that doesn't treat every "dead" line like it is fully energized.

 

[aczlan]

"If your transformer has a short in it" part of your reply I do not follow.

Sorry, wrote short, meant open winding or loose wire inside.

sdkubota I was taken back when could not find one 'confirmed' lineman death from a home generator. Not sure why I woke this morning with the BS detector going off on this subject. I can not see an 8000 watt generator boosting 120 volts to 7200 volt with ease or amperage.

8000 Watts (33 amps) of 240VAC boosted to 7200VAC would give you 1.1 amps (1100 mA). Per OSHA's formula you only need 7.2 mA at 7200VAC to cause vfib

Aaron Z

 

[Gale Hawkins]

I think it is possible to happen but we are still looking for the first confirmed report of a lineman being killed by a home generator. Lawyers for a utility company is interested in finding a "cause" not related to the company's policies or the failure to follow them. We know home generators can not kill linemen following policies in print and taught in lineman training classes.

 

[PAGUY]

WOW. I never thought this thread would take on a life of its own. A lot of good advice has been offered and I have always felt that you must respect electricity and NOT take chances/short cuts to wire something that can kill you or burn your house down.

Again I say thank-you to all who commented/offered advice.