a nickel question.....

[Fulthrotl]

anyone ever seen this done:

poco is down, and someone shuts off their main, locks the panel cover,
and backfeeds the house thru a plug feeding into the dryer plug, which is
fed off a 110 volt 2000 watt generator? both buses are fed thru each leg
of the 220 volt plug, the genset hasn't enough power to hurt anything,
and the house is fed... power comes back on, the genset is unplugged, and
the panel is unlocked, and power turned back on...

i know it's not legal, but how often does this turn up? anybody ever see it?


randy

 

[Dennis Alwon]

I see it all the time. Unfortunately it could be very dangerous because you are counting on an individual to remember to disconnect the main. I had done the same at my house years ago and in a rush to turn the generator on I forgot , fortunately for just a few seconds, to turn off the main. I would not trust that to anyone.

 

[iwire]

anyone ever seen this done:

poco is down, and someone shuts off their main, locks the panel cover,
and backfeeds the house thru a plug feeding into the dryer plug, which is
fed off a 110 volt 2000 watt generator? both buses are fed thru each leg
of the 220 volt plug, the genset hasn't enough power to hurt anything,

False, that generator can kill linemen.

As far as we know the line may be broken right outside the home.

i know it's not legal, but how often does this turn up? anybody ever see it?

Your right it is against the code.

It turns up very often

Never seen it personally but here about it all the time hear.

 

[SEO]

I see and hear about it all the time. This is an extremely dangerous and illegal practice. I've even heard this advice given to people from the generator salesman.

 

[infinity]

I asked this question to a few electricians on the job, who own generators, and they all said that they hook them up just like that. They didn't seem to see a problem with it because they would never forget to turn off the main.

 

[brian john]

Forget the main one time and as Bob said under the right circumstances this could be deadly.

That an electrician does this is above stupid, shows a disrespect of the trade.

THIS IS WAY TOO SIMPLE TO DO PROPERLY to allow screw ups that should know better to continue with this practice.

 

[iwire]

I should admit in the past we have done many large temporary generators and connected them without transfer equipment.

However when we do this we are actually working for the power company, we discuss with them how we will connect in and how we will protect all of us from accidents.

The most common way we do it is to use LOTO on the service disconnect with a lock on it from us and another lock on it from the power company.

This is allowed by 702.6 Exception.

 

[brian john]

I should admit in the past we have done many large temporary generators and connected them without transfer equipment.

However when we do this we are actually working for the power company, we discuss with them how we will connect in and how we will protect all of us from accidents.

The most common way we do it is to use LOTO on the service disconnect with a lock on it from us and another lock on it from the power company.

This is allowed by 702.6 Exception.

Bob under temporary circumstances were all parties involved are aware of the ongoing practice, and other safe working practices are utilized is different in my opinion from what is described by the OP.

And for residential application there are other methods that could be utilized that are inexpensive.

 

[iwire]

Bob under temporary circumstances were all parties involved are aware of the ongoing practice, and other safe working practices are utilized is different in my opinion from what is described by the OP.

And for residential application there are other methods that could be utilized that are inexpensive.

I agree 100% with all your points. :smile:

Really just wanted to point out the code compliant exceptions where conditions of supervision keep things safe.

 

[iaov]

Most of the DIYers out there have no idea how dangerous a generator can be to the lineman. They have no idea about how transformers work.

 

[480sparky]

I see several every winter, and occasionally after a windstorm.

I'm out repairing OH services that are down, and someone has gone down to Big Orange and bought a generator. A couple of male cord caps, some 10/3 NM, and they're made their own 'suicide cord'.

When I roll up, I tell them to remove all that crap so I can work safely. They tell me the main is off. I tell them, "I don't care, get rid of it. If you want your power back on, I'm going to make sure I stay alive today."

They reluctantly shut it off and remove it. I do my thing. I call the POCO for a reconnect, and tell them what I have found.

Not surprisingly, the POCO refuses to hook them up at all, even after the genny goes away. Their stance is they don't know if they'll do it again when the power goes out next time, and the safety of their crews is paramount.

Next thing I know, the HO is calling back, wanting a price for a transfer switch.

............And for residential application there are other methods that could be utilized that are inexpensive.

Very true, but they're only inexpensive if installed during normal circumstances. When mother Nature rips your service off your house, most HOs don't want to 'play by the rules'. They just start lining up at Big Orange so buy whatever they can to get the heat back on and the fridge running.

 

[Fulthrotl]

I asked this question to a few electricians on the job, who own generators, and they all said that they hook them up just like that. They didn't seem to see a problem with it because they would never forget to turn off the main.

and that, of course, is the fatal flaw, literally.

if the main is opened, there is no backfeed. screw that up, and you'll heat
up the primary peddler feeding your personal transformer with 5kv, or what
every the nominal primary voltage is. that will continue upstream until it
is interrupted by an open position.

and in turn, you'll heat up everything connected to that, as well as every
thing connected to the secondary side of your service transformer... i.e.,
all your neighbors... you will, in effect, become the poco.

'cept for one thing... you've now plugged in a genset to a *huge* load that
will overload the genset, and trip it out.....

which was what i observed in my neighborhood yesterday, when the power
was out for two hours.... after about 15 minutes, my lights flashed on, and
then off... and then, a minute later, again, and a minute later, again.
it didn't look like a poco trying to clear a line. so i got to thinking what might
cause something like that.... and remembered two years ago in my area, the
power went off, and did something like this, and when i measured the voltage
in one of my outlets, it was 60 volts, 120 volts across the 220 dryer outlet,
seems something similar was happening then..... hmm... just wondering what
all of your experiences with this were.....

 

[hillbilly1]

A couple of years back our local utility had a lineman killed because a homeowner did this, and forgot to kill the main. Don't know if the homeowner was ever charged, as this would probaly be considered involuntary manslaughter. I looked at installing a manual transfer switch at a poultry farm were they had installed a dryer receptacle next to the panel for hooking up a generator, the big problem was, they tapped the dryer receptacle AHEAD of the main, making it useless to turn off the main. Even though it had been that way for 10-20 years,it was lucky for the linemen and the customer, they had never had to use it. I've been in the big box stores during hurricane duty, hooking generators up for their store power, and hear their employee's telling customers to do the dryer outlet thing! Major liability!

 

[Mule]

Ive seen resi EC's backfeed through from the temp pole through the condenser circuit to panel .....for temp construction lighting.....

 

[480sparky]

Of course, turning off the main is a matter of faith as well.

Breakers are man-made devices, and do fail to operate as designed on occassion. So it's entirely within the realm of possibilities that even turning the main of fails to open the circuit.

 

[winnie]

I'm not disagreeing with the requirement for proper transfer equipment, especially when the minimum requirement for such equipment is little more than an effective reminder to turn off the main.

But as I read the original question, the generator could not energize the primary side of the transformer. Since a '120V' generator is being used to energize both supply legs, only 120V loads will be powered, and if the main is not opened, then the center tapped transformer secondary would look like a short circuit. (You have two opposite polarity neutral to 120V coils on the same core supplied by the same polarity of supply.)

-Jon

 

[tkb]

I should admit in the past we have done many large temporary generators and connected them without transfer equipment.

However when we do this we are actually working for the power company, we discuss with them how we will connect in and how we will protect all of us from accidents.

The most common way we do it is to use LOTO on the service disconnect with a lock on it from us and another lock on it from the power company.

This is allowed by 702.6 Exception.

The ones that I were involved in with the POCO, they required a visible break between them and the generator.
On one site we couldn't get the 4000 amp switch to open. the fingers were stuck. The grease was hardened.
We had to unbolt all of the fuses before they would let us start the generators.

 

[charlie]

Check out page 2. Even when you are careful, a generator can kill a careless lineman.

 

[pbeasley]

Ive seen resi EC's backfeed through from the temp pole through the condenser circuit to panel .....for temp construction lighting.....

Our house was like that for about 6 months while we framed in the 2nd floor. POCO had no problem with it cause they just moved the service drop to the temp pole and then back to the mast when we were ready.

 

[ItsHot]

Check out page 2. Even when you are careful, a generator can kill a careless lineman.

Charlie I could not get the page to come up. It is sad to know lineman have been killed due to backfeed. After natural disaters you always hear about the deaths due to generators, chainsaws,ladders etc.