Interlock locks to be used in lieu of transfer switch

[George]

Really? I think there are at least a few in everyday use...

A panel that has

[Howard Eisenhauer]

I'm coming in late on this, didn't see the original post but from reading the replies I'm infering Iggy wants to use a couple of keyed lock mechanical doohickies to prevent his genny breaker & mains disconnect from both being "on" at the same time.

This is, everyplace I've ever been, perfectly legal as long as theres only one key & it can only be withdrawn from the lock when the doohicky has the breaker in the "off" position. I've had a number of systems like this in sites where the feeds were physically seperated.

Now, that isn't to say I don't prefer a single changeover switch type of deal, 'cause I very much do, but the keyed switchs are perfectly acceptable if properly designed.

This has been discussed before somewheres on usenet, I remember posting on it.

H.

[Bruce L. Bergman]

Yes, a "Kirk Key®" interlock is legal - but ONLY where access is restricted to trained and responsible personnel like at power plants and industrial buildings. People who know what will happen if they screw up, and that they'll be held fully to account for it.

It is too easy to deliberately bypass that type of mechanical interlock and cause a backfeed, as easy as unbolting the front panel of the switchboard that the interlocks are secured to and operating the circuit breakers out of sequence. Takes only seconds.

And there are too many fools who are ready and willing to do it out of total and deliberate ignorance of the consequences.

For residential and light commercial/industrial applications where the transfer equipment is not secured and can and will be operated by untrained personnel, it HAS TO BE type accepted for that use. That calls for a pre-packaged automatic or manual transfer switch of some sort that has failsafes against backfeeds, and eliminates any "Kirk Key®" type systems from consideration.

Unless you want to be up for multiple counts of Murder 2 for backfeeding the utility service and killing a few workers on the line gang, out trying to restore power after the storm...

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[Vaughn Simon]

OK, you just went over the top.

Vaughn

[Solar Flaire]

It won't matter. Any inpsector worth more than two pennies will reject a voluntary interlock.

[Solar Flaire]

I am the local electrical utilty. You are confused and blaming unrelated things on lineman stupidity. Trained and legal linesmen do not take these chances. If they ever do, they are not linesmen anymore here.

[Bruce L. Bergman]

Not at all - a person properly trained in electricity theories, construction codes and the like would know the risks involved, and if he did cause a backfeed into the utility system anyway and someone dies, Murder 2 (done deliberately but with no premeditation) would be a reasonable charge to level.

Though I'd bet most career prosecutors would charge it as Murder 2 just so they could plea-bargain it down to an easy Manslaughter.

IANAL, but even 120VAC is a potentially lethal voltage. And when it kicks backward through a transformer and is suddenly boosted to 5KV to

35KV or more, then it's really easy to "reach out and touch someone."

And I have personal knowledge of how massive screw-ups of this magnitude can and do happen, but please DAMHIKT. Let's just say it wasn't pretty, and leave it at that.

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[Mark Rand]

What do you not understand? an interlock is not voluntary. it is an interlock.

Mark Rand RTFM

[Vaughn Simon]

I am both an electronics technician and a licensed electrician, so I think I have had a bit of training in electricity theories.

That is absolute bullshit.

Don't get me wrong, I believe in doing things right. In fact, I have a proper transfer switch on my own home. But why must this transfer switch conversation always disintegrate into such childish nonsense?

Vaughn

[Lectron_Nuis]

posted in response to

GB is an Inspector... in h i s head !

/smirk

I would also echo your words in:

------ Message-ID: xxxxxx I had to state that it's use would be illegal in each of those installations. I'm not that bothered about safety except where the lack of it endangers people, then I get quite particular.

---------

This particular waste of tissue (human), Solar Fart//Gymmy//Bengi, calling itself by whatever - in issuing its own qualifications, is prime example of endangering persons who would take what they read as Gospel. Denying _it_ the space to spread the garbage it does is an Act of selfless Good. cheers

Ln

[Chris Lewis]

According to Mark Rand :

If the devices are installed properly, and _present_. How would they be installed? Bolted to the panel face plate? What if the plate has been removed?

Not quite. A large DPDT knife switch is failsafe.

[Gunner]

There is a video on YuTube where a nutcase climbed a power pole..and a crew was trying to get him down. The audio segment can be heard "its ok..the power is off" followed by one of the guys grabbing a line to reach over to grab the crazy guy. Needless to say..the power wasnt off.

Ayup..not pretty.

Gunner

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[Ignoramus10518]

That would not connect the generator to the utility, however.

i

[daestrom]

Unless of course one blade comes loose from the handle and sticks in one position while the other blade moves to the other position. Some folks would notice that and probably do something about it, but a knife switch isn't 'failsafe'.

Designing relay and control systems to be truly 'failsafe' is a whole science unto its own. :-)

daestrom

[daestrom]

Nope. It's called, 'reckless disregard for others resulting in the death of someone'. In many states that fits the statute of murder. In NY it's not called Murder-2 since that is 'premeditated' while Murder-1 is 'causing the death of a law enforcement person while committing a felony act'. In NY it would be manslaughter in the first-degree.

All it would take is an accident and the DA being able to prove that you 1) had the prerequisite knowledge yet 2) choose to deliberately ignore the code requirements and that 3) your actions resulted in the death.

daestrom

[Ignoramus10518]

Let's be careful making legal judgments.

Making a mistake while trying to do a good job is not reckless.

"Reckless" in this context would be, for example, deliberately connecting the generator to utility side as an experiment.

i

[Vaughn Simon]

Are you a lawyer in real life or do you just play one on the Internet? If the former, can you provide us a link to a comparable case?

Frankly, I am tired of the silliness that always results from these transfer switch threads.

Vaughn

[gfretwell]

Although I would never advise someone to use a generator without a listed transfer device (and that can be a breaker interlock if it was tested on that panel by a NRTL) but I agree, these threads get silly. Your puny little generator will not handle "the grid" for more than a few miliseconds. When it hits the locked rotor of your neighbor's AC units it will trip out. Linemen are not going to die since they have procedures that assume NOTHING is dead until they prove it and then they short it out. I suppose if you did have a very localized failure you might light up a neighbor but the power company is likely to do that too when they restore power.

[Solar Flaire]

Call it what you like..it won't pass inspection and therefore an illegal device.

or

You could get an Electrical Engineer to put his stamp of approval on the design documents and state it's specific usage...maybe. Apply to CSA or UL for an approval. You may have to submit a few prototype samples to get the approval though.

[Solar Flaire]

It would if the live fed through your house load and back fed the neutral from the grid.

"Ignoramus10518" wrote in message news:nsidnT3z-uAyh9fbnZ2dnUVZ_o [e-mail]...