Square D makes generator back feed interlock kits for several of their
panels. I installed on in the new QO panel I recently installed.
You are correct, that link does appear to be hosed. This one works:
I don't believe these kits are applicable to panel models other than QO
and Homeline, even if the Homeline breakers follow the standardized 1"
I'm afraid you are out of luck on a transfer interlock kit as ITE/Gould
is no longer manufactured.
If you install a Square D feed through lug panel ahead of your existing
panel and add a generator interlock kit to it you will still come out
cheaper than the full sized transfer switch for the materials the labor
will be similar.
"This alternating current stuff is just a fad. It is much too dangerous
On Wed, 23 Aug 2006 20:32:43 GMT, "Tom Horne, Electrician"
Gee, don't tell the folks at Siemens Energy & Automation about that
- they bought ITE and Crouse Hinds and Murray (and a bunch of
others...) and a lot of the old stuff is still in production and
available by special order. That, or they have published an approved
substitution cross list for newer breaker lines.
They're still making new ITE Pushmatic breakers, and I know there's
a 'rocker' style two-breaker interlock for them - I have one. Don't
have any IDEA where I'll ever use it, but I have one.
If you must use SquareD stuff, at least stick with the Homeline line
which is ALMOST "Industrial Interchange" size. (The bus stabs are
slightly different, but you can make others fit in a pinch.)
If SquareD ever goes belly up, the proprietary bus QO stuff will be
a problem to get replacements for. Reference Zinsco and Federal
Pacific - You can get the 'Made Somewhere in Asia' cheap replacements
from UBI, but IMNSHO they're downright dangerous.
--<< Bruce >>--
But at least they work.
My luck with Homelines is abysmal. Since 1991, 3 of 4 homeline
breakers in the pony panel to the Jennair cooktop have died.
They trip, and cannot be reset. [Even after removal from the panel ;-)]
I've never experienced _any_ other breaker failures (and I've worked
on a fair number of systems of varying manufacturers).
Chris Lewis, Una confibula non set est
It\'s not just anyone who gets a Starship Cruiser class named after them.
I never intended to imply that parts were not available but that does
not make my statement that main breaker interlock kits are not
available. Since the panels themselves are no longer manufactured there
is no likelihood of such an interlock kit becoming available.
I perceive you are a fan of so called universal breakers. Are you aware
that the use of any breaker that is not laboratory listed or recognized
for the panel in which it is installed is a violation of the US NEC.
The use of so called interchangeable breakers in another manufactures
panel is usually done in violation of the local electrical code. This
is why professional electricians often carry the more expensive Thomas &
Bettes breakers to use in universal panels because Thomas & Bettes is
one of the few manufacturers to have their breakers tested for use in
other manufacturers panels.
"This alternating current stuff is just a fad. It is much too dangerous
On Thu, 24 Aug 2006 17:12:42 GMT, "Tom Horne, Electrician"
I don't ever plan to deliberately use the "wrong" breaker, I carry a
decent selection of both Murray/Siemens 'MP'-'QP' AND the Cutler
Hammer/Challenger 'CH' on the truck, even though they overlap quite a
bit - but they are the two dominant players in the market and you need
to use the proper breaker for the panel. And I carry a decent
selection of GE THQL/THQP and a smattering of Homeline.
But 25 years from now when you can't get the "right" breaker for the
panel, if they're all using a standard form factor someone else's will
fit in a pinch. If it's a proprietary form factor, all bets are off.
T&B's best 'substitution' product is the Zinsco Q and R38/RC38
clones, those I keep around. And they are type accepted, unlike the
Taiwan UBI knockoffs.
NEC is important, but the customers also need their lights,
refrigerator and furnace on for the night too. You can track down the
"right" breaker on Monday, or get all the parts together for a proper
Panel Change to a modern panel without it being a total panic rush
because the customer is in the dark.
--<< Bruce >>--
Hey Iggy, what most folks do when installing a "Whole House" transfer
switch, is to:
1. Have the electrician make arrangments for with the Power
Authority to have a reconnect schedualed after figuing about
how long the job will take, then break the seal and remove the
Meter, replace the wires from the MeterBase to the Main Breaker
with wires long enough to reach thru the short connecting conduit
between the Main Panel and the Transfer Switch and connect to the
Grid side of the Transfer Switch.
2. Add the wires from the common side of the Transfer Switch back to
the Main Breaker in the panel.
3. Have the Power Authority Guy inspect the work, replace and reseal
4. Finish wiring in the Genset on the Genset side of the Transfer
Switch, and your DONE, except writing the the cheque to the
electrician, for his services.
Bruce in alaska
Bruce, thanks. Couple questions.
Would you say that the better place for T.S. is inside, as someone
else suggested, rather than outside?
Can i use [more flexible and easier to work with] properly sized
I would install the Transfer Switch as close to the Main Panel as
possible. Typically, adjacent with a 1 1/2" Dia. nipple in between,
as you can run the new wires from the MeterBase into the Main Panel,
and thru the nipple to the Transfer Switch, and then from the Transfer
Switch back to the Main Breaker. This keeps the runs short, and makes
for centrally located Home Power Managment, as you may want to drop
some of the loads offline in the Main Panel when running OffGrid on
You can use any UL 600V Insulated wire, of the appropriate size for the
current, that suits you. It is the Insulation Rating that the Inspector
will be looking at. Typically Welding Cable isn't rated at 600V, so you
may have to find a suitable wire that has the UL Insulation Rating
approprite to the service.
Bruce in alaska who likes Welding Cable for Battery Jumpers and
Inverter Dc Feedlines.......
It would be best there, but you might want a safety switch before
that... You're going to make me go get my copy of NEC aren't you?
The new one has a whole section on transfer switches and generator
connections - and I didn't memorize the darned thing.
But with your luck, your local codes are locally written and totally
different. They really aren't standardized that well.
Make it easy on yourself - Call your local city/county building
inspector, make an appointment for a pow-wow and talk it over, ask
him/her what he wants to see. You can over-engineer it and make it
"perfect" - but why? KISS.
You could stick it to one side of the meter socket, and put a big
nipple or fitting between the boxes - but it's not the preferred
method. You would have to send the 'Utility In' and 'Switch Out'
power going through the same conduit and through the same meter socket
can, and it would be too easy to get an accidental backfeed out onto
the utility lines. ESPECIALLY if someone else gets in there and isn't
clear on the concept.
I'd put the transfer switch off to one side of the main, and abandon
the wires going out the back of the meter socket can directly to the
house breaker panel. Make a new house feed out the back of the
transfer switch going inside to the house breaker panel. And at the
bottom of the transfer switch you put a landing-lug box where the
leads from the portable generator tie down.
Try to lay it out so the wires inside the transfer switch can do not
physically cross inside the can - so if the wires get all hot and
melty (technical term, I know...) they can't make an unintentional
I've always seen them in commercial situations with the Utility Main
Breaker placed ahead of the transfer switch, so they can open that
breaker as a drop-dead "No Way In HELL it can backfeed" safety. The
extra safety step makes the utility linemen working on the snapped
lines much happier when they hear a generator running way off in the
That way you still have the separate Fire Alarm disconnect in
parallel with the Main Breaker as a place to monitor whether the
Utility Power has come back up. (For a business they might turn off
and lock the Main and kill the lights for non-payment, but they have
to leave the Fire Alarm feed on or the insurance coverage goes away.
And it's also a Life Safety issue.)
In a residential situation, if you want to change over the entire
house on the transfer switch you'd need a separate fused switch or
enclosed breaker to power the monitor light. And get the concept
cleared by the local inspector. Otherwise, how do you know for sure
when they've got the utility power back on?
If it's a safe place to make a hole, you can get a pilot drill and a
knockout punch and blast a hole through the side of the can in about
two minutes. They can't put knockouts everywhere anyone could
possibly need them, or the can would fall apart...
"Perfect" is an unreachable goal unless you are Bill Gates and have
a ton o' money to spend on "Perfect" - Lets see here... A 40KW or
60KW genset with a ton of excess motor- starting oomph and automatic
transfer switch, a large fuel tank, and a big UPS inverter running all
the critical systems in the house as hold-over - That'll only cost you
25 grand or so to set up...
The lights go out partially, you hear a very muted engine cranking
and starting outside, and 15 seconds later all the lights pop back on
like nothing happened, and will stay that way for days. And the
genset is big enough that no power budgeting is needed, you can be
working in the shop on the lathe with the AC up full blast while the
Mrs. is baking in the electric oven, no worries.
--<< Bruce >>--
Is this 200 amps at 120, or 200 amps at 240? You have 240 service, but are
the amps 200 from hot to hot, or the sum of each leg to neutral? 200 amps
at 240 is 48kw. I question because 48kw is vastly in excess of typical
residential power requirements. Consider the possibility that the next size
down the 100 amp unit, is the fit. The 200 amp unit is a HUGE box! It's
designed to switch a 48kw hot load.
We have a master disconnect. The transfer switch is located between the
master disconnect and the main panel. We use a second transfer switch to
disconnect optional loads, and shunt them directly to a 2nd generator.
I have a 240V panel, and the breaker says "200" on its handle. It is a
breaker that would open if current through one of its legs exceeded
200 amps (that's a nominal rating, meaning that it would allow for
momentary overcurrents to some extent).
While I rarely use 43 kW of power, I do at times use a lot of
power. Example. I am TIG welding in my garage, my wife is cooking a
lot of food on the range, my A/C is running, etc. That could easily
add up to 140 amps or more (and would be a very rare occurrence).
Well, I would surely be happy to use a smaller and cheaper box, if it
was possible, but it is my understanding that the rating of transfer
switch should match the rating of the house's electrical service.
Well you could put in a sub panel and put the transfer switch in the
feed to the sub panel
I have been following this tread because I am thinking of going the sub
The down side is you have to decide which circuits will be on the sub
panel. I my
case its only the well. the outlets in the kitchen and the lights in the
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