Emergency Generator Connections

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tonype

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New Jersey
I very rarely (once a year maybe) see an emergency generator - came across 1 today and have several concerns (see photos).

1. The generator is in the garage - combustion gas build-up problem plus the unit blocks access to the main disconnect.
2. One concern I have is the connections to the main breaker. The load side of the breaker (Siemans QJ22B200 - about 12 year old) is triple lugged (Problem?) - one of the cables appears to be a the "back-feed" into the system from the generator transfer switch assembly. The other services one of the panels in the home. At least one of the strands of one of the conductors are snipped to fit into the breaker.
3. Are there any rules for generator sizing? I would have expected some type of limits on the area of coverage for the generator (I usually see a standalone panel dedicated for emergency power) It appears that this generator feeds or backfeeds into the entire system (systems I have seen in the past typically only supplieds the bare essentials (heating systems, refrig. etc).
4. What would prevent the generator from back-feeding the entire grid?

Any insight would be appreciated.
http://i15.photobucket.com/albums/a352/TonyPE/100_2141.jpg
http://i15.photobucket.com/albums/a352/TonyPE/100_2140.jpg
http://i15.photobucket.com/albums/a352/TonyPE/100_2139.jpg
Regards,
Tony Shupenko, PE
 
Nice installation. NOT. (Bet you haven't heard that one in a while). Let me go backwards on your questions. #4-hopefully, the transfer switch will prevent back feeding. #3-I don't believe there is a code preventing a generator from supplying the whole load as long as there is a proper installation. #2-definitely a violation. I've never seen a standard residential type main breaker rated for more than 1 conductor. #1-I guess a combustion type of equipment running in the garage would make them candidates for a Darwin award.
 
That looks like a bad joke:-?

where do you start.
1. panel clearance
2. exhaust ventilation
3. multi wires under single lug
4.etc..etc..etc..
 
JJoyce said:
That looks like a bad joke:-?

where do you start.
1. panel clearance
2. exhaust ventilation
3. multi wires under single lug
4.etc..etc..etc..
Click to expand...

4. etc.etc.etc. = Tap rule violation
5. cables not supported within 12" of enclosure
6.GEC not brought to neutral bar
Rick
 
This installation screams of no inspection because of no permit. The main breaker isolated the wiring for a jack-leg to do while de-energized, but no POCO involvement.

Same with a "service upgrade" where only the conductors on the load side of the meter have been upsized. I've had more than one of these fall into my lap, one with a fire.

If wired correctly, the T/S could still prevent back-feeding, but the service cable should have landed in a panel instead of being tapped like it was to protect those conductors.

Those T/S's come in 100a and 200a sizes, and that copper NM (combined in a lug with aluminum, no less) looks more like #6 to me, nowhere near a 100a capacity.
 
Whenever I hear the talk of self certification for electricians, this is when I will use this picture to convince people that inspectors are a necessary part of construction. (regardless of whether a real electrician installed this or not)
 
Tony, one small point to remember: This is not an EMERGENCY generator in NEC terms. It is a STANDBY generator, more specifically an Optional Standby Generator.
 
Looks wrong to me. Shouldnt you have to disconnect the neutral as well in all instances of a generator to limit the possibility of backfeeding the guy at the pole? Would love to see when the power is back on and they dont turn the generator off first, moltan metal lava in the face. Did the same people who installed this install a bright red light in the kitchen to monitor when the main utlilty power is back on line?,,,LOL
 
after i look at the photo i was little started about the location of stand by generator.


the main 200 amp breaker it was not ratied for more than one lug at all

what really puzzle me how they can run #6 NM to the TS that really annoy me a bit

this set up i will say it really quick this is good chance it will win the darwin award for sure

Merci , Marc
 
Tony, there is a 6-3(?) leaving the disconnect, and one leaving the transfer swich, both going up. Where do these go?

No matter what, this is simply a bad job all the way around
 
Now I have a concern about my standby generator. I am sharing the neutral with POCO. It is not switched. Only the two CCC are switched. I switch off the main breaker manually, then switch on the generator breaker. The neutral is always connected. I do not have TS. Do I need to switch the neutral? I have tested my system and have had no issues.

Feedback Please.......No pun intended....lol
 
JohnJ0906 said:
Tony, there is a 6-3(?) leaving the disconnect, and one leaving the transfer swich, both going up. Where do these go?

No matter what, this is simply a bad job all the way around
Click to expand...

Sorry for the delay - from what I deciphered, the cable out of the top of the main disconnect does to one of the distribution panels (three are present). The one out of the T/S goes to another (the other wire from the T/S feeds back to the main disconnect - this initiated by concerns (amongst the multitude of concerns) that this generator is feeding the entire home and possibly back into the grid). I should have taken a photo with the T/S cover removed.
 
John Valdes said:
I switch off the main breaker manually, then switch on the generator breaker. I do not have TS.
Feedback Please.
Click to expand...
What you have is illegal and lethally dangerous, unless your main and generator breakers have an approved interlock. You or anyone else may forget to turn off the main breaker, and kill (yes, kill) a lineman.

Transformers work both ways. If you feed 240v into a 19.9Kv-to-240v distribution transformer, you will be sending 19.9Kv into a primary line that the POCO is working on, and presuming to be dead. (Pun intended)

No bull; many linemen have been killed by this very scenario. More than one have told me that nothing strikes greater fear in them during a power outage than hearing the drone of a residential generator.

When I was younger and stupid, I did the same thing as you. "I'll always remember." We professionals tell ourselves that we know how to break the rules properly. Well, this is one rule I will never break, ever.

"Feedback Please." You've got it.
 
tonype said:
Sorry for the delay - from what I deciphered, the cable out of the top of the main disconnect does to one of the distribution panels (three are present). The one out of the T/S goes to another (the other wire from the T/S feeds back to the main disconnect - this initiated by concerns (amongst the multitude of concerns) that this generator is feeding the entire home and possibly back into the grid). I should have taken a photo with the T/S cover removed.
Click to expand...
If that is a transfer swich, it will not feed back to the entire home-assuming it is hooked up properly. It TRANSFERS power for the one panel from utility (wire from main disconnect) to generator and back again. When the generator is off, you have to have power from somewhere, right?
 
JohnJ0906 said:
If that is a transfer swich, it will not feed back to the entire home-assuming it is hooked up properly. It TRANSFERS power for the one panel from utility (wire from main disconnect) to generator and back again. When the generator is off, you have to have power from somewhere, right?
Click to expand...

So, if I am understanding this, this generator would then only be supplying power to one of the 3 panels (cable coming out of the top of the T/S). The wire from the main disconnect is running to the T/S and not vice versa. Now this is sort of making sense. Normal POCO stuff goes from the main disconnect to the T/S and then to the panel (out of the top of the T/S). When power is off and generator on, the generator feeds to the bottom wire to the T/S and out of the top and not back to the main disconnect.

Let me know.

Thanks.
Tony
 
tonype said:
So, if I am understanding this, this generator would then only be supplying power to one of the 3 panels (cable coming out of the top of the T/S). The wire from the main disconnect is running to the T/S and not vice versa. Now this is sort of making sense. Normal POCO stuff goes from the main disconnect to the T/S and then to the panel (out of the top of the T/S). When power is off and generator on, the generator feeds to the bottom wire to the T/S and out of the top and not back to the main disconnect.

Let me know.

Thanks.
Tony
Click to expand...
Correct-as long as the transfer swich is wired properly. Judging by all the rest of the installation....
 
JohnJ0906 said:
Correct-as long as the transfer swich is wired properly. Judging by all the rest of the installation....
Click to expand...

It looks to me that is at least wired properly (as far as function is concerned. The install is something else.) If I were to hazzard a guess, the HO had a 200 amp house panel. The installer separated that panel into a subpanel for the desired circuits. The wire from the top right of the ATS goes to the new sub-panel, the other similar wire coming from the load of the main is now feeding what the generator does not control under outage. The two wires are too similar to be coincidence. I am not sure what the other original feeder under the load lugs are. Unless there are multiple panels in the house. The HO and installer THINK all they have to do is open the garage door when it is running (that unit exhausts to the left), but an automatic system is going to come on whether you are home or not. Let's hope it is a detatched gargae that stays open all the time.:grin:
 
tonype said:
. . . the other wire from the T/S feeds back to the main disconnect - this initiated by concerns . . . that this generator is feeding the entire home and possibly back into the grid.
Click to expand...
Looking carefully at the third image, showing the entire "install", it looks to me like that cable supplies the utility terminals of the T/S. T/S's have three power connections: the utility power input, the generator input, and the load. The second and third are obvious.
 
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