ECN Forum Forums Photo Discussion Forums Violation Photo Forum Found in a hotel in Nashville, TN

Found a cord with a male cap on each end used to backfeed a receptacle.



[This message has been edited by Joe Tedesco (edited 03-25-2005).]

Did you chop it into small pieces?

Get ready to see many more of these things!

Various energy codes are specifying more and more "renewable" energy be used. Plus, we all know about the price of oil! So...here comes solar!

A popular "trick" of the DIY co-generator- usually some dolt who ASSUMES the utility won't "let" him make his own power- is to use such a device to feed his 'bootleg' or 'guerilla' solar into the grid.

I saw this "advertised" in Mad Magazine sometime in the sixties. For testing outlets, plug one plug into the outlet, and use the other plug to "feel" the voltage with your fingers.... Sure.

This is a 2005 NEC violation of 406.6 (B) Connection of Attachment Plugs. Attachment plugs shall be installed so that their prongs, blades, or pins are not energized unless inserted into an energized receptacle. No receptacle shall be installed so as to require the insertion of an energized attachment plug as its source of supply.

Yes!

PS: The white and black wires were reversed!



[This message has been edited by Joe Tedesco (edited 03-24-2005).]

Standard type item for connecting the generator to the house during a power outage. NOT!

On a side note I know a lineman what was nearly killed when someone used one of these. During an outage a power customer in my hometown (an electrical engineering professor at our local university) plugged their generator in using this type of cord and backfed the power gird. The lineman working nearby received a shower of sparks and quite a zap. I don't know the complete specifics of how. After the incident his hair began to turn white. Do this day he has white hair. I'm not kidding. True story.

I'm not sure if he had any grounding devices in place to protect himself or was in the process of installing them. Anyway it was the talk of the town when it happened. The college electrical engineering processor definitely had his tale between his legs for some time. Luckily it wasn't manslaughter charges.

RSlater,
RSmike

NAHHH guys, this is simply a circuit breaker locater, plug it in and go look for the breaker that popped.

Huh?

I am unable to find any humor here since this situation could have been the cause of a serious accident!

For the record, I post these pictures here in this forum, as I have for a few years so that people will see the kinds of things thatUNQUALIFIED PERSONS do, especially those who work in and around a hotel!

I actually found this being used in the hotel where I was presenting my seminar to over 20 people this week, and when one of my students told me about this in the "restaurant" area, I pulled it out and told the manager that he could be put in jail if anyone was hurt!

He thanked me!

Wiring is No Hobby!
http://www.nachi.org/bbsystem/usrimages/M/MECA_JT.jpg

Joe Tedesco, Member MECA

I was quite serious about the generator cord. I've seen more people with these things. When I say anything people look at me like I'm nuts. And I'm serious about the injured lineman. He spent time in the hospital and his hair did turn white and still is. If people would just spend the extra cash for a transfer switch his person would not have been injured.

Joe, can you give more information on why this the hotel needed this type of 'device'. Why did they need to backfeed something? The only other time I've seen the 'need' for something like this is because someone made some type of power distribution box and was backfeeding it because they didn't purchase the proper devices to do it correctly.

I agree with you. The unqualified people have no clue about what they are doing. I n longer like to go into the electrical sections of home improvement centers because I have to overhear what some people are planning.

RSlater,
RSmike

What about that picture someone showed of some receptacles installed on a tree-trunk. A similar arrangement was picking up power from one socket and back-feeding the other one.

Hope you saved the plugs, though, Joe. Those are the good quality ones.

At the risk of being politically incorrect, I hereby name this device the "San Francisco splice", defined as two males joined back to back :-)

For an example:

{ Link removed -- Original thread deleted }



[This message has been edited by pauluk (edited 03-31-2005).]

"For an example: { Link removed -- Original thread deleted }
So this thread was deleted.
Probably a good idea. It sounded like we had a DIYer that was going to do something stupid, despite every ones advice.

[This message has been edited by IanR (edited 05-03-2005).]

RSmike:

Here is the original installation where the left receptacle was supplying another on the opposite wall that was used to power a light for the hotel restaurant menu!

I've seen this sort of thing suggested on more than 1 web site to hook up the portable generator. Even more amazing (scary) is the staunch defense of the method if you challange them about it. (Just open the main and it is perfectly safe!)

Is that white zip cord I see emerging from the outlet cover on the left outlet? I don't think that that's code.

No that was not a zip cord, it was a telephone line that was passed through to a phone on the other side of the wall.

"Is that white zip cord I see emerging from the outlet cover on the left outlet? I don't think that that's code.
Joe Tedesco-No that was not a zip cord, it was a telephone line that was passed through to a phone on the other side of the wall"

Cerainly not code. Violates separation of HV:LV wiring. But considering the seious safety issues here, a code violation is the least of thier problems.

Yes, it's gone now. I've removed the link above to avoid confusion as the thread number has been reused for a new topic.

It's been done on this side of the Atlantic as well. Aside from the dangers of a two-plugged cord, no matter how careful people think they might be in opening the main, when the lights go out and there's a scramble to get the genset running, there will come a time when they forget.

Either that, or someone else will run the generator without knowing the "proper" improper procedure. The rules are there to protect the world from the ignorant.

I've been on more than one job where another electrician set up the connect with a double-plugged cord. I told the homeowner about the error, but two years later, it was still the same.

Just the other day, when I came home from work and looked in the garage, I saw one of these monstrosities laying there. It was a 6-30 dryer cord attched a length of 14-3 with a 5-15 plug. Needless to say I was taken aback. "What the heck is this and how did it get into my garage?!" After dimantling this death device inquired about it to my family members. Turns out a well meaning, yet un informed, neighbor dropped it off so I can connect my generator during the next hurricane. I am going to have a talk with him about this widowmaker the next time I see him as I am sure he has one these and intends to use it.

These "Suicide" cords are obviously a real danger to anyone plugging them into a live outlet (or two...).

However I am dubious of stories about linemen and home generators.

If one of these were used with a generator to back feed a house during a power outage, the generator would attempt to power the entire grid downstream of the utility fault through a 5-15 outlet and it's 20amp (or 15amp)Circuit breaker (or fuse). Assuming the utility fault is an open, 20amps or so is not going to power dozens if not hundreds of dark houses. Even with a huge generator and a 14-50 (or 10-50) range plug Suicide cord the load of an entire neighborhood of houses is going to trip a breaker or stall the generator.

If the utility fault is local enough to only affect one or two houses then the lineman would not be expecting dead lines. Also he should hear the generator at such close range.

If a lineman did encounter the power from a back fed generator it would certainly not have enough power behind it to cause big sparks or other thermal effects.

A much more likely cause of Lineman injury/death would be inductive coupling to other live power lines or most likely the unanticipated re-energization of the segment he is working on.

In any case ALL lineman injuries/deaths from these events are avoidable by following mandated grounding procedures!

I would like to hear any accounts of back fed home generators that caused injury/death or even a tingle to a lineman. I assume any investigators would confirm that the generator was actually the source of the current in question.

Sample procedure; measure voltage at site of accident, turn off generator, re measure, restart generator, re measure to confirm cause and effect.

Jim, there are scenarios that can and have caused the deaths of utility linemen.

One scenario is where the distribution-voltage line is interrupted between the transformer serving the house with the generator, and the rest of the grid. The generator back-feeds the local transformer, producing distribution voltage (typically 7,200 to 22,000 volts) on the supposedly "dead" lines. The amount of power that can be delivered by the generator is more than sufficient to kill someone working on the lines.

Agreed there, add to that the probability that the cause of the outage may be a storm, and you have a soaking wet lineman up a pole, probably at 3 am on a sunday, who is really *not* expecting 7200 volts from a transformer that's disconnected from the grid. Given the howling winds likely, he/she is also probably not going to hear the generator. Agreed, safety is the lineman's responsibility, but there's no excuse for using something suicidally and homicidally dangerous when transfer switches are very readily available.

You know, this brings up an area in which I am both ignorant and leery.....backfeeding the PoCo lines.

Most places have "net metering", where the homeowner can generate their own power, and feed any excess back to the PoCo.

The "Alternative Energy" press quite freely asserts that the idea that this might endanger a lineman is simply a canard put out by the evil PoCo, that "their methods prevent this." How? I wonder?

A lovely as self-reliance and energy independence may be, this attitude, and the cavalier attitude of some in the alternative energy field (and the ignorance of the rest) toward the NEC causes me concern.

Add to this the fact that all of my few encounters with home generation have been to correct major goofs made by the installer, and I am not reassured!

Yes, the casual attitude about backfeeds and other safety issues among some alternative energy folks is pretty scary. The causes seem to run the gamut from sheer ignorance (the majority) to outright hostility toward the "evil gridmongers" and their employees.

Inverters intended for use in net metering arrangements are supposed to incorporate circuitry that prevents backfeed to the grid in the absence of grid power. In the event of a utility dropout, the inverter goes into a standalone mode until grid power is restored. Even then, most power companies require a visible break disconnect switch installed on the outside of the building, where it is accessible to POCO personnel.

SOME alternative energy publications TRY to get it right. The "Code Corner" column in HomePower magazine is a great attempt at explaining the NEC requirements (and the reasoning behind them) to the alt-energy DIYer. Now if they would just dump the "Solar Guerilla" pieces where they show how to install systems WITHOUT inspections or PoCo approval, they would be doing a REAL service to everybody...

In SolarPowered's & Chipmunk's scenario the house would have to be the only load on the transformer.

Even if the generator could not be heard the fact that the house had lights would be a big clue that a generator exists.

Anyone who grabs a wet 7200V line because they "think" it is dead is Darwin award material.

Except in very rural areas the transformer could easily be backfed by another transformer (this is more common than generators).

"There are scenarios that can and have caused the deaths of utility linemen."
My request was info regarding any documented cases, not just the fact that it could happen under the right combination of errors.

Statements that it did happen somewhere sometime with no further information are barely hearsay, let alone evidence.

The cord isn't the danger to a lineman it is the implied lack of an interlock between the genrator feed and the utility feed.

Example, an electrician connects a temporary generator during a power outage using a cord with male end connected to a breaker that will be removed when generator is disconnected.
If the main breaker is lockedout (&tagged)
how is this less safe to the lineman than a transfer switch?

What NEC rules have been violated?

The problem is that someone backfeeding a generator into the house wiring may forget to turn off the main breaker. The transfer switch is designed to make sure the user disconnects the house wiring from the POCO and connect it to the generator. The transfer switch requires only one action, where the "backfeed the generator and shut off the main breaker" requires two separate actions. Which might not get done. It's a bit like the rules at the shooting range: "put the safety on, take the magazine out, keep the gun pointed to the floor, and never aim at anyone". Redundant, but with something that can be lethal, you need redundancy.

I agree this not for the untrained.

We all do many thing everyday that are potentially lethal to us and others.

Locking out the main before connecting the generator is a very simple proceedure compared to driving a car or shooting a gun at the range.

A transfer switch takes it to idiot proof, similar to only being able to fire the gun when it is actually pointed at the target.

I am NOT advocating the backfeeding of utility lines. I am merely trying to better understand the mechanisms of danger and assign some relevance to them.

Closing your eyes and firing a gun is dangerous. But if you are alone in the woods the danger is different than on a crowded sidewalk downtown.

The generator danger occurs when ALL of the following occur at the same time:
1. Power line breaks between single house and grid.
2. Generator operator fails to isolate main.
3. Lineman does not measure line.
4. Lineman fails to install ground.
5. Lineman touches line on transformer side of break knowing that he is violating his work rules regarding #3 & #4.

#2 is prevented by a properly installed transfer switch.

If the Electrician is incompetent to lockout the main, is he competent to install the transfer switch?

A tranfer switch is the best solution.
What level of operator competency makes other solutions viable?

True, but surely we're talking about a situation in which an untrained, non-electrician will be doing the transfer most of the time?

All of us here at ECN might be capable of safely locking out a main and making a temporary connection for a generator in an emergency situation where power is needed right this moment and there's no other way.


I don't think that means that we should install such as a system as the standard method though, and certainly not where an unskilled householder who doesn;t really understand the dangers is going to be using it.

I suppose, whenever we consider taking a "shortcut," we should consider what one cynic told me:

"As soon as you make something idiot-proof, they come out with a better idiot."

I have discovered a "Suicide lead" in a basement garage for two apartments. The shared garage had two socket outlets, one fed from each apartment for laundry purposes.

Mr Upstairs yanked the load the wire out of his meter and back-fed his apartment with the dodgy lead in the two sockets in the garage.

Mr Downstairs found it " a bit strange " when his power bill had doubled a few months earlier, but only voiced concern to the landlord when he noticed that the garage door opener stopped working when the strange lead was pulled out of his socket by the laundry machine in the garage.

The PoCo meter reader had read the meters 5 times ( 5 months ), looking straight at the yanked out 16mm phase cable with tape over the end, and didn't say a thing.

Epilogue : Mr Upstairs vacated said premises the same day. No forwarding adress. Mr Downstairs received cheque from PoCo

I hate to admit it on here, but I have a generator cable like that. Well, not EXACTLY like that, I at least wired mine up to go from my 240V 20Amp generator to a 240V 30Amp dryer jack with #12 wire. Besides, so long as you disconnect the mains first, it's perfectly safe! I mean, I don't exactly have a kirk key on there but it's not like my family or I make a habit of playing with the main breaker. Not that I'd recommend this to a laymen.... And oh man the lady at the checkout at lowes gave me a "I hope you're not planning on doing what I think you are!" when I roll up to the checkout with a generator, a dryer cord, a handy box and 25' of romex. "It's OK, I'm an engineer!"

Re: risk to linemen, I don't think there is much, if any risk at all of someone not closing the main and energizing the lines- a typical 20 or 30amp generator would trip it's own breaker or stall with just the hot water heater or A/C on the homeowner's own panel, forcing them to shut off every breaker in the house (including the main) but the most critical lights & receptacles before bringing the generator online.

At any rate, it's way safer than the double-ended plug I made from an old interior-grade ungrounded extension cord to plug my shed in because I'm too lazy to dig the conduit and finish wiring it up right (ducks). Don't worry about my shed bursting into flames though, alas, the suicide jumper is no more. Damn thing scared the hell outa me anyway, I don't know what I was thinking... See, now I have a NEMA plug wired directly into the panel so I can just plug in my shed to an extension cord like any normal "small" appliance (ducks again). I hope I'm providing a good professional role model for the vocational students browsing this forum!

[This message has been edited by SteveFehr (edited 12-02-2005).]

Maybe, but if the house is on a single transformer, and the primary is feed is open before the next transformer, then the primay will be energized by the generator without loading it down.
Don

Would not the typical inrush current required to energize a typical utility 15 to 30KVA transformer trip the generator's circuit breaker instantly?

I've read of folks using pole pigs in reverse to build tesla coils, and they HAVE TO use series resistance to energize the LV side of the pole pig, otherwise the breaker trips instantly from the extremely high inrush current.

... My dad used to make stupid things like that,..until I found them in the garage/basement and killed them all..he would save old,broken receptacles and switches,cracked porcelain keyless fixtures,even old boxes with all the KO's taken out..so whenever I was over doing any work,I'd make a habit of breaking the devices up with my linesmans,so he couldn't use them again...he got sooo mad...
Russ

And I hope you're kidding!

Of course, those who say that they'd never forget to throw the main are the only ones who would use this method to begin with, and are the ones who injure and/or kill linemen.

At least, look into buying a replacement panel cover with an integrated interlock mechanism that prevents the main and the (usually) top-right breaker from being on simultaneously.

No. Most generators cannot produce enough current to open a breaker in the instantaneous or very short time trip ranges. Also with a large inrush load the voltage output of the generator drops to limit the current.
Don

corrected typos

[This message has been edited by resqcapt19 (edited 12-12-2005).]

Wouldn't that stall the average home generator then, even if it didn't trip the breaker? It would be like a huge brake slamming down on the output shaft!

I have fortunately never witnessed it myself- but some fellow sparkys have seen first-hand just what happens when the PoCo and a generator get in a duel.

Best description: Shrapnel and molten metal flying aeverywhere, as the genny goes "ka-boom!" Or the faulty transfer switch. Or, whatever component is the "weak link."

We're not talking about a little smoke coming from the windings; nor are we talking bout a stalled motor. We are talking about the equivalent of a very big line-to-line fault. Something has to give- and it won't be on the PoCo side!