Steps for installing a transfer switch

[Saul]

Whats in that box with the wheels? Looks interesting

 

[Ignoramus4235]

Whats in that box with the wheels? Looks interesting

generator.

http://igor.chudov.com/tmp/onan/Diesel/

i

 

[Bruce in Alaska]

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
the meter.
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, 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
welding wire?

i[/QUOTE]

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
the Genset.

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.......

 

[Ignoramus4235]

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
the Genset.

OK, I like this idea a lot. I will do it exactly as you say, all my
doubts have been resolved.

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.

OK, I will definitely look for suitable 600v rated wire -- the
flexible wire is so much easier to work with, it is worth the extra
$$ -- not that much for just a dozen feet or so.

i

 

[ATP*]

Just what formula do you use to conclude that a particular generator
is "undersized".

Let me give you some examples of load in my house

- 220v kitchen range/stove, 50A breaker, probably 40A use under
certain conditions

- 28A central air conditioner

- 15A window A/C (115V)

- Various motors, I would say 10a max at 220v. (refrigerators, gas
water heater, freezer, sump pump)

- Lighting, a lot of compact fluorescent, but not all, could go up to
2 kW (say 10A 220v)

- Spa heater, 15a 115v
- computers and TVs, 1 kW

That adds up, unless I am mistaken, to roughly 23 kW. That would be
almost "worst case" electricity use, not counting my welder and
compressor or other possible loads.

Would you say that a generator below 23 kW is "undersized" for my
house?

Or would you use some common sense and recognize that electricity
usage could be reduced by taking just a few steps, such as turning off
the A/C units, not using the kitchen range and turning off the pool
heater.

If the latter is the case and you recognize the fallacy of wanting to
power everything at once, then look at my power usage under the
following conditions:

1) No A/C use
2) No kitchen range use
3) no hot tub heater use
4) Use of half of other loads (fewer TVs, computers etc)
5) not all motors running always at once

I hopet hat you agree that the above is quite reasonable for emergency
situations.

Then energy use comes to, if I did not make a mistake, 3-4 kW.

My generator is honest 7 kW. That means that it can produce 7 kW
continuously, stopping for oil changes and other maintenance only, as
a prime power unit. It is not some Home Depot "7kW peak load" POS.

That leaves plenty of extra power from my 7 kW generator. Enough to
probably run one small burner on the kitchen range, or a window A/C
(this one is more questionable), a lot of light, furnace and water
heater, computers, TVs, tools etc.

So. Can you explain why you called my generator "undersized".

Thanks.

i

I am not telling you to get a generator big enough to power everything in
your house at once. I am saying that having all that load connected to the
generator and relying on someone (which might not be you) to turn breakers
off to control the load is not good engineering design. Good design is
putting your emergency circuits in a transfer switch, in some reasonable
relation to the size of the generator.
Just as a note, compressor starts on your refrigerator/freezer are quite
taxing on a generator.

 

[Bruce L. Bergman]

I would like to install a real transfer switch like this one

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=42163

Our house is wired for 200 amps, so this is the right size for us.

I plan on getting a proper permit, but I want to understand the work
involved.

Here's a picture of our power meter:

http://igor.chudov.com/tmp/onan/Diesel/z02_Installed/dscf0209.jpg

I understand that the proper electrical placement of the TS is to
place it between the power meter and house main breaker. It is the
physical layout that has me confused.

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.

The meter has a prepunched hole to the right, below the utility seal
line. Not sure if it is helpful. After the meter, the electric cable
goes right inside the house, to the panel that is right behind the
meter (maybe 1 foot long).

The question is, how to install a transfer switch here. I aam
obviously unable to open the meter to look, since it is sealed.

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
cross connection.

What is the normal location of the transfer switch? How is it usually
connected to the meter box?

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
distance.

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?

I would think that if, hypothetically, the meter box had a prepunched
knockout hole a little above the meter, then I would tap there quite
easily, but it does not seem to be the case.

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...

I want to do a 100% perfect job here, that would be inspected and all,
so I want to do it right. Any good assistance would be appreciated.

"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 >>--

 

[Ignoramus4235]

I am not telling you to get a generator big enough to power everything in
your house at once. I am saying that having all that load connected to the
generator and relying on someone (which might not be you) to turn breakers
off to control the load is not good engineering design. Good design is
putting your emergency circuits in a transfer switch, in some reasonable
relation to the size of the generator.

Remember that there is a breaker right on the generator. So nothing
terrible would happen if it became overloaded. It would just turn
off.

I looked at available transfer switches that switch several circuits
only, they do not do what I want. I have no interest in continuing
this discussion.

i

 

[Cydrome Leader]

Remember that there is a breaker right on the generator. So nothing
terrible would happen if it became overloaded. It would just turn
off.

I looked at available transfer switches that switch several circuits
only, they do not do what I want. I have no interest in continuing
this discussion.

It's about time.

You come here begging for help, knowing nothing at all. The when you get
advice you complain because you know better.

It's pretty tiring and lame.

You're such a pro, just connect the generator as you wish and be done with
it. Why do you need to keep coming back here to talk about it? You've
already decided what approach you will take.

 

[Snag]

Where I live I dont need to call them to shut off my power I just
pull the metor out just outside my back door.
I called them to let them know that there was no seal on it and that
the glass was cracked he said "so what" None of the metors in this
town have seal wierd eh!
Made replacing my main panel alot easier.

My meter has been without a seal for several years now . Called the power
company when I first broke the seal to work on my breaker box , they never
came out to replace it . My panel was replaced recently too - after I looked
inside and saw the AC breaker arcing on the tab .
Got a buncha poles not being used - yet . Also got the capacity to wire
my shed/shop properly now , with it's own box . Which is where I'll feed the
main panel from next time I need to use the generator .
Betcha if my power usage goes down significantly they'll be out with a
seal . And a warrant . Only ones that get to steal from the utility company
here are the people in charge ...
--

Snag aka OSG #1
'76 FLH "Bag Lady"
BS132 SENS NEWT
"A hand shift is a manly shift ."
<shamelessly stolen >
none to one to reply

 

[Cydrome Leader]

Iggy has been on alt.energy.homepower for over a year that I
recollect. He asks for opinions, not "help". He is excellent on

Nonsense. Anybody needing an opinion for everything they do has no either
no knowledge or confidence in what they're doing in the first place.

 

[Ignoramus20689]

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.

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).

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.

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.

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.

sounds interesting.

i

 

[Bill Janssen]

i

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
panel rout.
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
kitchen.

Bill K7NOM

 

[Ignoramus20689]

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 panel rout. 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 kitchen.

In my case, I have a lot of circuits, most of which supply some
important loads but draw very little current, like compact fluorescent
lighting. So choosing only very few of them would inconvenience me
greatly.

i

 

[Ignoramus18055]

You have identified the correct switch. A two hundred ampere main
breaker results in the need for a two hundred ampere transfer assembly.
Be advised that a main breaker interlock kit will achieve the same
result at far lower cost. What brand and model is your main breaker
enclosure; such as your main distribution panel?

ITE Gould. It accepts Homeline breakers for branch circuits.

i

 

[Marty Escarcega]

I would like to install a real transfer switch like this one

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=42163

Our house is wired for 200 amps, so this is the right size for us.

I plan on getting a proper permit, but I want to understand the work
involved.

Here's a picture of our power meter:

http://igor.chudov.com/tmp/onan/Diesel/z02_Installed/dscf0209.jpg

I understand that the proper electrical placement of the TS is to
place it between the power meter and house main breaker. It is the
physical layout that has me confused.

The meter has a prepunched hole to the right, below the utility seal
line. Not sure if it is helpful. After the meter, the electric cable
goes right inside the house, to the panel that is right behind the
meter (maybe 1 foot long).

The question is, how to install a transfer switch here. I aam
obviously unable to open the meter to look, since it is sealed.

What is the normal location of the transfer switch? How is it usually
connected to the meter box?

I would think that if, hypothetically, the meter box had a prepunched
knockout hole a little above the meter, then I would tap there quite
easily, but it does not seem to be the case.

I want to do a 100% perfect job here, that would be inspected and all,
so I want to do it right. Any good assistance would be appreciated.

i

P.S. I would like to avoid suggestions like "just get a little 6
circuit emergen transfer switch", it is not the right one for our
situation.

Most times a new sub panel is installed, those circuits fed by the
generator are moved to it and the transfer switch is installed between
the old panel and new.

Why would you want to run EVERYTHING? That's a helluva big generator
needed.

Mostly critical loads, like lighting, refrigerator, freezer are put on a
generator.

Marty

 

[Bruce L. Bergman]

Ignoramus16089 wrote:

I'm afraid you are out of luck on a transfer interlock kit as ITE/Gould
is no longer manufactured.

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 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.

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 >>--

 

[Chris Lewis]

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.

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).

 

[Bruce L. Bergman]

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.

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 >>--

 

[Stephen Carlson]

Hello everyone:
This is my first post to this group, and I've been following this thread.
First, the NEC states that the conductors from the service entrance to the
main breaker (not being fused) should be as short as practicable.
Personally I would be very reluctant to install any equipment upstream of
ANY breakers.
Second, a sub-panel can be arbitrarily large, limited only by the maximum
breaker size allowed in your main panel. If you know that you are not going
to use certain loads, don't install them. Or move EVERYTHING over to the
sub. You will stilll have the safety of a breaker ahead of everything, and
you can take your monitor light off the main panel.
Just my 2 cents.