Interlock locks to be used in lieu of transfer switch

[sparky]

The OP was talking about a keyed interlock with maybe ONE key or maybe many more keys.

I should have explained more clearly.

[Chris Lewis]

According to Solar Flaire :

Nonsense. Otherwise every large scale auto-start generator/UPS (including the _humungous_ ones we have) would be illegal.

Yes, they'll have manual switches as a disconnecting means, for test etc. But that doesn't mean that when the system is in normal operation it can't operate the transfer switch automatically.

Backfeed elimination is isolation for linesman protection. That's what transfer switches do.

Linesmen aren't human?

[Chris Lewis]

According to Solar Flaire :

What makes you think it _isn't_ disconnected inside the meter base?

Did you find schematics for the thing?

[Chris Lewis]

According to Solar Flaire :

Let me get this straight. HD Canada, which has purchasing independent of HD US, has agents that somehow manage to get confused about which country they live in, except that they get it right for just about everything _but_ transfer switches, and continues to spend money buying, stocking and shipping expensive objects they can't and won't sell?

I really really don't think HD is that dumb. They'd be broke if their inventory management system was that broken.

[gfretwell]

No but we still get a lot of canadian quarters in our change. The point is, does the CEC deal differently with separately derived sources and things that are not SDS?

In the NEC, if you don't bond the neutral in the generator you don't switch the neutral. The SDS does have the grounded neutral in the separately derived source.

[Michael A. Terrell]

It will kill you, if you aren't man enough to handle it.

[Michael A. Terrell]

it looks like you'll never know:

OrgName: Golden Triangle On Line OrgID: GTO Address: 236 Victoria St N 2nd Floor City: Kitchener StateProv: ON PostalCode: N2H-5C8 Country: CA

ReferralServer: rwhois://rwhois.golden.net:4321

NetRange: 216.59.224.0 - 216.59.255.255 CIDR: 216.59.224.0/19 NetName: GOLDEN-BLK-4 NetHandle: NET-216-59-224-0-1 Parent: NET-216-0-0-0-0 NetType: Direct Allocation NameServer: NS.GOLDEN.NET NameServer: NS2.GOLDEN.NET Comment: RegDate: 2003-10-16 Updated: 2005-04-25

RTechHandle: FD194-ARIN RTechName: Dominguez, Francisco RTechPhone: [phone] RTechEmail: [e-mail]

OrgTechHandle: FD194-ARIN OrgTechName: Dominguez, Francisco OrgTechPhone: [phone] OrgTechEmail: [e-mail]

[Michael A. Terrell]

You're right. Somebody either has a hardon for HD Canada, or they only have a couple working neurons.

[Chris Lewis]

According to Dan Lanciani :

You'd have to install a jumper on the neutral bar to the special generator plug I guess.

[Obviously it wouldn't work as stated, because the meter plug doesn't have a neutral.]

There's a patent on that:

If you can get past the patent idiocy of being able to unwind your power meter by rotating the meter 180 degrees ;-)

Note that if the generator doesn't bond ground and neutral, you apparently don't have to switch neutral.

[Dan Lanciani]

In article , [e-mail] (Chris Lewis) writes: | According to Dan Lanciani : | > In article , | > [e-mail] (Chris Lewis) writes: | > | > | This device conceptually just makes the meter base larger, and has | > | provisions for security sealing it too. Otherwise, FPL wouldn't | > | permit it. Obviously they do. | > | | > | But I would imagine that the local power authority has to approve | > | of the device before they'd allow you to install one. | > | | > | [I believe that contractors have to contact the power | > | company to inform them that the meter base has been diddled | > | with so they can come out to reseal the meter.] | > | | > | If you were to somehow get a hold of one up here, you really should | > | call the power company before installation. | > | | > | > Is UL listed the same as UL approved? | > | | > | Yes. Which means it's approved up here unless it runs afoul of | > | something specific in the CEC, or Hydro throws a fit. | > | | > | [Ontario Hydro has two separate "special" meter trial programmes going | > | on, similarly restricted in region. "Smart meters" and something | > | else I forget...] | > | | > | To tell you the truth, I'm _very_ much surprised I haven't seen | > | something like this before. It's the obvious place. It's | > | just not something a homeowner is usually able to install | > | themselves .... | > | > One concern I have is the neutral/ground connection between the base | > and meter. To the extent that it exists at all it is not intended to | > handle much current; most split-phase meters are 4-wire devices. I | > assume (hope?) that installation of the adapter involves some sort of | > jumper which in turn might require an additional lug to be added to the | > original base. | | You'd have to install a jumper on the neutral bar to the special | generator plug I guess.

Right. And that of course might involve installing an extra lug or a different bar. (The typical meter base here has either two full- sized neutral lugs to join the incoming and outgoing feeds or that plus a smaller terminal for a local grounding electrode conductor.) It's too bad since it is so close to a plug-and-play solution... but not quite. :)

| > | An even simpler way would be to have some sort of object that "mimics" | > | the back of the meter and has a plug for the generator. Power out, yank | > | the meter, install the adapter, plugin the generator, and voila! | > | | > | When power comes back, pull out the adapter and plug the meter back | > | in. | > | | > | Problem being that you'd have to get the power company back to | > | reseal the meter after grid power is restored. | | [Obviously it wouldn't work as stated, because the meter plug doesn't have | a neutral.] | | > In addition to the neutral/ground problem, what if you accidentally | > install the adapter upside down? Around here bases are typically | > symmetrical so I'm not sure you could make the adapter failsafe | > against back-feeding without modifying the base. But then you'd | > want to arrange that the adapter couldn't be inserted into an | > unmodified base which would make the base incompatible with a | > normal meter... | | There's a patent on that: | |

Yes, that solves the easy part. As I said, you can modify the base such that the adapter plugs in only the right way (and still support a normal meter or even one modified per that patent). But what you really need is to prevent the adapter from fitting an unmodified base at all--otherwise somebody is going to plug into the wrong base and back-feed. Once you've gone to all that trouble and added a neutral connection you might as well replace the entire base with one that includes a generator plug. Maybe that should become a standard product for new construction.

| Note that if the generator doesn't bond ground and neutral, you apparently | don't have to switch neutral.

Yes, the NEC recognizes generators connected not as separately derived systems. None of my transfer switches switch the neutral. Interesting thing about my transfer switches in connection with the original part of this thread: they are not DPDT knife switches but pairs of DPST knife switches with a mechanical interlink. I assume this is done to avoid making the boxes extremely deep. These are UL listed Cutler-Hammer units professionally installed and inspected.

Dan Lanciani ddl@danlan.*com

[john]

Rachel Carlson did the world an injustice and in the long run did more harm than good with her book on DDT. The biggest problem with DDT was that it was over used, applied way to heavy and it did cause some problems because of it but they could have been prevented by proper use.

You want to kill fleas..... one application of ddt will wipe em out completely. All the other stuff doesn't work half as well even with a heavy application.

John

[Rich Grise]

Carson.

What's in "Black Flag"?

Cheers! Rich

[Solar Flaire]

I guess you know about the Loonies here then.

[Solar Flaire]

OK y'all got me now. What is SDS?

I don't necessarily agree with switching all conductors in all cases and I think it is for the reason you have stated. I am not positive on this one but I think there are no exceptions, bonded or not.

If the neutral is never bonded then a back feed can never happen...hmmmmm. But then if a conductor isn't bonded then it requires overcurrent protection, isolation and must be continuously ground detected too.... they win.

[Solar Flaire]

Schematics for a piece of metal sold as ian interlock kit by Square D?

Try to keep up.

[Solar Flaire]

[Solar Flaire]

What do you expect for minimum wage?

HD opened here with all these "trade experts" in every isle. They thought they would clean up the market. many long term building supliers closed down for fear they would never compete. Five or six years later, HD has no experts left, not even the industrial accident ones. You can't get anybody to serve you, let alone know anything about a trade tip. The plumbing isle has a guy that has heard of PEX pipe and another that doesnt know the difference between PEX-AL-PEX fittings and even one of the 6 different types of PEX fittings, if you can find him not busy in the shingles sales isle.

..and you want them to know and understand the electrical safety code too? Most of them are having a hard time knowing that a 1/2" knockout isn't a physical threat.

[Solar Flaire]

You have a definite comprehension problem. How many time have I explained you have twisted the meaning to something that wasn't posted?

Read again and think. "where would I use this device in a large automotive plant?" and "when did manual become automatic?"

[Rich Grise]

Take your pick:

Cheers! Rich

[Solar Flaire]