ELECTRICAL Question - kind of an emergency

Anonymous-0

Well-known Member
Ok, here's the deal, I am well aware that back feeding a service panel is against code, and has the potential of energizing the secondary, and the primary circuits back through the transformer, it violates code etc. etc. Well understood there.

However, and I hold no one responsible for any advice, we have some real serious problems here, this ice storm has created a bit of a disaster and I've got to do what I can here because the temperatures are supposed to drop into the teens.


Here's the deal, I've got a Miller NT 251 Trailblazer, 8500 watts continous, a quad 115 outlet and a single 240 30 or 50 amp outlet on it to provide power. I have 50 feet of AWG #6/3 to which I can wire up the 3 prong male plug, this is the largest conductor it will take according to the sheet. I can run this to an outlet inside the garage, which is as follows:

In the garage, I have a 250v/125v outlet, ( reading off the cover) that is wired circa 1978 gray conductor is labelled Alcoa - (must be aluminum) #4 AWG, assume it to be 3 conductor, with a ground, it goes another 50 feet or so to 1 of my pair of 200 amp breaker panels, that are fed by the main service line.

1.) If I were to backfeed to this panel, using the above scenario, assuming the conductor to be large enough to use, directly from the 240 or 250 outlet on my Miller NT 251, would in turn the branch circuits from the panel be 115 volts, if the panel is fed 250 from the generator. I assume so, but am no electrician.

2.) Ok, main breakers will be off, and no one but me is here, but as another precaution, I can cut the seal on the meter box and pull the meter. Will that effectively break the circuit, meaning it's wired in a series, ( if that is a reasonable way to describe it ) meaning once you un plug it, the circuit is open, cant be closed etc. and this eliminates the hazard, obviously bending the rules, but we are in a real jam here.


3.) The intended load on the branch circuits are an oil fired over hot water furnace, well pump submersible type, 1 refrigerator, 1 lighting circuit, all these are 15 or 30 amp breakers. This is all I need to keep things going here.

Aside from the obvious, if this scenario is a serious hazard, I won't do it, however, if it will work, as described, I need to know, cannot take a chance with frozen pipes etc. and I've got an elderly person here, my mother, to look after, other wise I'd rough it out, or could just go with a bunch of heavy duty extension cords, directly, still won't get me water or heat, kind of has my back to the wall.

Again, one time I could really use some sage advice, be it good or bad, I've got to consider this option due to the circumstances.

Hopefully anyone else in this mess is coping, most of us are still in the dark as to the extent of the damage and how the power company is doing on the restoration, is what it is, time to dig in here and ride this out.
 
not being an expert electrician so i cant advise as far as whats safe or not. but, years ago we had a huge tornado go thru the area, power was out for better than a week. having a well and all the stuff in the freezers was an issue. in the shop was a 50 amp 220 welder plug. i took a 220 line from my generator, made up a pig tail, pulled the mains in the house and backfed power thru the welder plug to get the well back and the freezers. not saying it is the best scenaroi, but, when you got nothing else, you got to make do. pulling the meter socket is a good idea, i think. from what i been reading, you guys up there got a real mess with the ice storm. best of luck to you, be safe, glenn
 
try theepicenter.com/tow01076.html or if that don't work you can probably get there by googleing the epicenter and going to their tip of the week pt 2 and find out what you need to know. If the power is out how are you running your computer? Don't have to answer that, save your electricity.
 
Hi Billy,

Sorry to hear that you're in such a tough situation. Before I had read more than a couple of lines of your question, my thought was, if you pull the meter you completely isolate your system from the utility company's grid. You've thought it through. It's physics, not magic. You could tape an explanatory warning across the meter base to address the far fetched possibility of someone other than yourself being the person to put the system back in operation.

Buickanddeere is the person who most frequently points out the causes and potentially calamitous consequences of of ill-advisedly running a generator back through a residential electrical system, so I'd hope to have him check in with advice on the matter.

Good luck, Stan
 
Quote "to which I can wire up the 3 prong male plug." Unquote
How are you on the internet with the power off?
A problem unaddressed here is that you are energizing the bare ground wire, using it as a current carrying conductor.
At best the voltage drop on the ground conductor will leave everything connected to ground. A few volts above true earth potential. Livestock won't be drinking from any anything grounded. Or touching anything grounded without a fuss.
I've seen grounding systems with high resistance connections and/or open connections. If that is anywhere in your system. You can be bitten with 120V between "grounded items" and true earth. And even between two "grounded items". Also your 120V loads will see anything from a smoldering to a smoking 1 to 239 volts.
I have to ask everybody here? Why have you yet to install a proper transfer switch after being told for years? "Install a transfer switch or wish you had before it's too late."
If you want to make this "farmer fix" work "better". Connect the four pin stove receptacle where there is a proper neutral and ground.
Why can't some of you get it through your heads? Ground and neutral are not the same thing?
 
Billy, First of all your home service and that service entrance panel is for 120/240 volt single phase 3 wire. Iffffffffff the generator is indeed the same, basically a single phase transformer which has 240 volts between its ends L1 to L2 and has a center tap that serves as the Neutral, YES if its connected such that its L1 and L2 feed the panels L1 and L2 (which it will if it serves a 240 volt Receptacle) 240 volt loads served from the panel youre backfeeding will indded "work"
The next thing is your generators Neutral needs to be tied to your panels Neutral if you want the 120 volt loads on BOTH legs of your panel to work when backfed from the generator. To do that by backfeeding a receptacle you would need to use a receptacle THAT HAS AN ISOLATED NEUTRAL AND I DONT MEAN THE BARE/GREEN EQUIPMENT GROUNDING CONDUCTOR. The problem is most common 240 volt 3 pole grounding receptacles are for 2 hots and an equipment grounding conductor and DO NOT have a Neutral terminal. To have 2 hots and a Neutral plus an equipment grounding conductor you would need a 4 pole receptacle !!!!!!!!!!!!!

NEXT Its my best guess that Generator you have has its Neutral bonded to its iron frame and the NEC allows it to serve plug n cord connected equipment WITH NO OTHER GROUNDING SUPPLIED TO THE GENNYS IRON FRAME. However, if you were doing this properly and wanted to use just a 2 pole transfer switch (switch the 2 hots but NOT the neutral) the service and gennys Neutral would be bonded BUTTTTTTTT you would be required TO DISCONNECT THE NEUTRAL TO IRON FRAME BOND IN THE GENERATOR

SOOOOOOOOOO my reason in explaining all this is merely to point out the problems I see youre running into in backfeeding a receptacle are that I suspect youre going to be mixing Neutral (a grounded conductor) and Equipment Grounding Conductors (a grounding conductor) AND THAT CAN CREATE A HAZARD under certain sets of circumstances

NOTE Im NOT saying this wont work, Im only saying I dont think youre correctly dealing with all the Neutral versus equipment grounding conductor issues let alone the fact that the generators Neutral would NOT be bonded to the frame as described above.

Of course removing the meter will isolate what youre doing from the utility for safety as would throwing the panles main breaker.

Again, what youre doing can work but there are Neutral versus Ground issues but since what youre doing is already a violation I guess a few more may not be of concern??

Just be careful n stay safe and it sounds like youre well aware of preventing backfeeding the utility so thats one hazard youre preventing

Best wishes n God Bless

John T Longggggg retired electrical engineer and rusty as an old nail on the NEC but do my best to help yall
 
I'm glad you posted John, The genset is not grounded although the case may be bonded. If it were a permanent trans-genset it would be grounded because it becomes a separately derived source.In a temporary situation I know I would do it.
Richard..Old retired electrcian
 
BuickandDeere: I think part of the problem could be that the neutral and ground all come together at the main panel. Just a thought. Not trying to be argumentative, 'cause I learn much from you, but in all my three prong outlets and plugs, the neutral is insulated. I don't think he would be energizing a bare conductor. I don't know about the circuit for an electric range, as we burn gas, but I would think that it would be three insulated and one bare. It would make the more sense to use the four prong circuit, as that is what i see on all the gennies that I have looked at. Also wouldn't flipping the main breaker serve the same as using a two pole transfer switch? It would still be dependant on the person to remember to go out in the weather and throw the switch. I see many manual transfers for sale, but have to really look for automatic switches. I am hoping to install a genny in the near future, but I want to install an auto switch between the meter and the service box, but if I am going to do that I also need to replace the Federal Pacific box that is out there. No project is as simple as first planned. Thanks for your thoughts.
 
Quote" and a single 240 30 or 50 amp outlet on it to provide power. I have 50 feet of AWG #6/3 to which I can wire up the 3 prong male plug," Unquote

He's wanting to use the ground prong of a 240V plug as a neutral.
That three pin 50amp welder receptacle is 240 not 120/240 like a stove four pin receptacle.

The issue is neutral current on the grounding system.
The service panel bond between ground and neutral is not for the ground to carry neutral current. It's to hold the neutral line to near true earth potential. And to keep the 120V lines from being more than 120V above earth potential.
 
Nothing is guaranteed safe, that's why they have insurance and inspectors. That said, If I had to do it, I would drive ground rod and ground genset and do it. Years ago this would have been common. Retired electrician master and his buddy retired electrical engineer who uses this same hookup. I now have transfer switch. God bless and be careful.
 
Yes, I agree on that, and this is the first place I came to post a question about this, and they tell it like it is, may not be what you want to hear, but what you need to here.

Now if this was concrete, I'd have a good understanding of it, but see what happens when I fool with electricity ..... better to get the facts on the table, trial and error does not mix well with electricity.

Good news is here, our circuit was repaired, and we have power, but a most people are still out and there are still a lot of trees just about ready to fall or drop limbs, never heard anything like this, the cracking of timber for almost 24 hours now, our woods are now a real mess.
 
I ran a direct line, extension cord into my office here in my home, and I actually got a connection through dial up, analog, even though most phone lines are stretched to the brink of coming apart. Was tough to get the connection to stabilize though, kept timing out. Thought it best to ask here, before I ran out of time, with the cold air moving in, but now the power came on, lot of others are still out and will be for awhile
 
Again, thanks to all, for responding, I really appreciated this, power miraculously came on here, while so many others are still out, sure does not take much ice to really screw things up, that is for sure !
 
Like you said, sometimes you have to do what you have to, but with electrical service, and not having the expertise to figure out what would be best, glad the folks here responded, discussed this scenario, was a big help, power is back on though, oddly enough but true, losing freezers with food in them is a real kick between the legs, aside from what made the power go out.

Sure looks like a mess, just these cold temps coming in, kind of makes you worry about all the other folks out there with no heat, red cross has opened shelters, I hope these people are coping, not easy this time of year.

Must have been our turn for an ice storm, we've been lucky for the most part, my neighbor has some big willow limbs down, missed his house at least, amazing how often you hear the timber cracking, splitting and or shearing off.
 
Get a tranfer switch.An oil furnace can be wired with a plug and receptical.Water pump can be set up the same way.Generators dont have to be run full time ,Friend tried it, used 10 gal of gas in 24 hours with a small unit.Beware of carbon monoxide when using a generator.
 
Thanks Richard, good post...... Yep those lil typical aux gensets do have their case bonded to their neutral and it serves as its own grounding electrode system and youre allowed to use plug n cord connected equipment WITH NO OTHER GROUNDING OF THE GENSET. However, youre correct and we agree it looks like if you wanna use it to feed your home service and bond its Neutral to the Homes Neutral (obviously necessary for 120 and 240 use) and only switch the 2 poles L1 and L2, THAT GENSET N TO G BOND MUST BE SEVERED.

Take a look at my post up above, thanks again n take care now John T retired electrical engineer
 
REPEAT OF POST ON OTHER BOARD

Billy, from your response I can see you heard what I said and are taking this seriously, this thread is gettin a lil long so I will just throw out a few things as a final statement hoping to educate yall:::: One cant explain in a few paragraphs here what it takes books and years of study to comprehend...

NEUTRAL First of all its A GROUNDED CONDUCTOR. Its grounded cuz in the service entrance panel its bonded to the ground buss i.e. its GROUNDED and its also a carrys current.........

Its necessary because its effectively the mid center point of a 240 volt transformer which is why from either end L1 or L2 theres only one half the voltage i.e. 120 volts, so thats how you get 240 votls PLUS two legs (L1 to N, L2 to N) of 120 volts from a 120/240 volt single phase 3 wire service.

Now, if all the 120 volt loads were perfectly balanced with the exact same currents on BOTH L1 and L2, there wouldnt be any Neutral current, HOWEVER it carries the loads imbalances otherwise.

GENERATOR. Its typical for a 120/240 volt single phase 3 wire portable generator that it supply plug n cord equipment and theres NOT any requirement that the frame be grounded. It has its Neutral bonded to its iron frame which serves as its own GROUNDING ELECTRODE SYSTEM...HOWEVER if you use such a generator as a backup to feed your home electrical system and DO NOT WANT TO USE A 3 POLE TRANSFER SWITCH (i.e. ONLY switch the 2 hots) then the generators neutral DOES NOT BOND TO ITS IRON FRAME (you remove that bond/jumper/connection). Also in such a case the gennys iron frame, as other non current carrying metal enclosures, is bonded to the EQUIPMENT GROUNDING CONDUCTOR (the bare/green) THEREFORE WHEN USED IN THE SCENARIO ABOVE (remember theres danger in bonding a Neutral to the Equipment ground buss at places OTEHR THEN one single place at the service entrance) the generators Neutral to frame bond must be severed such that its iron frame is still safety electrically grounded (to bare/green equipment ground buss) and so that youre not mixing neutral and ground together AGAIN at a place downstream from the service entrance. One last time, the gennys N to G bond is severed,,,,,,the gennys Neutral needs to be bonded to your panels Neutral (so 120 and 240 both work) ,,,,,,,,,the iron frame of the gennys still needs itself to be grounded,,,,,,,,BUT YOU DO NOT want to re bond any N to G downstream from the service entrance SO REMOVE THE GENNYS N TO G

BACKFEEDING USING ONLY A 3 POLE RECEPTACLE

Same problem, a 240 volt 2 pole 3 wire grounding receptacle ONLY has 3 terminals, L1, L2, Ground........If you do what I think you intend YOU ARE MIXING NEUTRALS AND GROUNDS.
What you would need would be a 4 wire receptacle, 2 hots, Neutral, ground......

Without getting too long, if you mix n match neutrals and grounds at places other then the single points at the service entrance, and given the certain hazardous combination of open and shorted conductors YOU CAN ENERGIZE THE EQUIPMET GROUND SYSTEM so when you come on contact with a metal frame of an appliance YOU CAN DIEEEEEEEEE

The bare/green EQUIPMENT GROUND BUSS and the NEUTRAL BUSS are boned only ONCE at the service entrance NOT AGAIN DOWNSTREAM so you gotta be careful with these backfeeds and transfer switches and aux generator hookups.

Yall stay safe n have a Merry and Blessed CHRISTMAS its a celebration of the birth of Jesus Christ and despite atheistic objections, its A FEDERAL HOLIDAY......

John T Long retired Electrical Engineer and a lil rusty on this stuff but still believe this will keep yall safe
 
Yeah, you're right on that, would just have to temporarily re-wire and run heavy cords, and would not have ruled that out if I had no other options, about 10 def F right now, not a good time to be without power.

Lot of people have made the mistake of not respecting carbon monoxide, and running things like generators, mine is in my yard/driveway, really use it just for welding, but I am going for the dedicated back up generator, transfer switch, propane powered, also to include provisions to allow me to connect this Miller NT 251 as a back up to that, this way it's all legit and done right, from here to New Hampshire there is still 1/2 a million people without power and might be for days to come, real mess out here.
 
Thanks buickanddeere and JohnT and all the others. I got so involved in how to use your answers in what I am planning, that I didn't pay near enough attention to the original posters' situation. It is making good sense now.
 
I took it for granted and didn't expand on the issue of the neutral's path.
The neutral connection of the service transformer is at the half way point between the 240V line 1 and line 2's windings.
240V loads flow from Line 1 to line 2 and have nothing to do with neutral or ground.
120V loads from line 1 or line 2 have to flow back through the neutral TO the center point of the transformer's 240V windings. NOT to some rod stuck in the dirt somewhere.
Hence the three, not four wire connections from the service transformer to your distribution panel. Line 1, line 2 and the current carrying conductor called neutral. It maybe at "neutral potential" but it's as hot as a firecracker.
The connection to earth at the distribution to neutral keeps the neutral to "near" earth potential. And keeps line 1 and line 2 to "only" 120V above earth potential.
So when somebody makes a path through themselves between either line 1 or line 2 and earth. The most they are going to get shocked with is approx 120V. Without that neutral reference the lines and neutral could drift thousands of volts above true earth potential.
 
hi billyi also have a miller trail blazer welder.what i did about a year ago was had a new breakerbox put in with the flip breaker when the welder generator is on the main is off and cant be turnrd on untill the other one goes off. i have a wire 75 foot long rolled up along side the house like a garden hose would be it will reach my truck where i park it in the driveway and it works great for me i live out in the boonies and the power goes off everytime the wind blows hard always knocking a tree over somewhere. RICK
 
Christmass is a Pagan Holiday, invented by Catholics === if your catholic, enjoy yourself, if not --- your doing the Pagon Tradition ///

IF Jesus Christ was born during that time -- it would be recorded in the Bible --
 
>IF Jesus Christ was born during that time -- it
>would be recorded in the Bible

So what time is recorded in the Bible as when Jesus was born? If no time is specified, does that mean he was never born?
 
Very Good Question, Yes Jesus Christ was Born, but His Coming was not that Important, the Reason He came (( IS IMPORTANT )) .. IF Jesus wanted us to know the Date of His Birth, He would have told us ....

Luke 2: 7 & 8 tells us that Jesus was born in the Fall of the Year, when Shepherds where in the Field, and they SURE Where NOT IN THE Field in the Winter .... does that help...

I know YOU have a Birth Date, how would you like it if we celebrated your birth day on April 1st. ( April Fools Day ???? )
 
A bit late but here is a very good outdoor manual transfer switch. It even lets you add 4 or 8 extra breakers for outside receptacles/loads.
It simply bolts in after the hydro service meter.

http://www.reliancecontrols.com/ProductDetail.aspx?TWB2012DR
 

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