Boy, you sure did get a lot of contracictory information. See a
couple of my inline comments below, too.
I am NOT suggesting this is a do it yourslef job unless you are
qualified.
I purchased an Emergen Transfer Switch and installed it.
I bought a length of appropriate cable and the conntectors and
built a cable to connect the generator to the transfer switch.
The outdoor "disconnect" is the plug at the generator.
The cord comes in thru the wall and plugs into the Transfer
switch.
The transfer switch has ten switches (breakers): The are
wired as follows:
One 220 pair for 1 HP well pump (that's a ganged set of 2
brkrs used).
One for the furnace,
None for AC; power problems here are always winter.
One for water heater, set of kitchen outlets, and ceiling
lights in two rooms.
One for lights in three other rooms
One for outlets in main living areas; living room,
bedroom, etc.
One for computer room. Don't run your computer off a
generator unless you have a power conditioner.
The rest go to whatever was handy in the panel: lights,
outlets for coffeemaker, microwave, gas stove, things like that.
The big advantage of a transfer switch is that it allows you to
turn things on or off at will, thus minimizing what's energized
at any one time, plus it makes it impossible to feed power back
into the power lines outside. Each switch on it has three
positions: Power from generator, all OFF, power from outdoor
lines.
In our case, the only time we have any problems is if the well
pump and say the freezer or fridge turn on at the same time, or
the furnace fan joins in. The turn-on surges are high enough
that they pull the power down so far the generator really lugs
down hard to start them. That's very hard on electric motors and
puts excessive wear and tear on the generator. So far we've
never popped a breaker on the genset, but that's because we're
careful about which switches we turn on at the same time. The
Transfer Switch breakers are a set of ganged 25A for 220, plus 4
20A, and the rest 30A. It's oversized a tad at 7500W capability,
but that was my choice in order to be able to control various
things.
In general, you want your genset loaded to about half of its
rating or less for extended periods of time. Beyond that you are
causing excessinve wear and tear on them. There ARE better
generators, but one pays a fortune for them.
It passed code inspection first time with not even any minor
recommendations other than I hadn't yet fully plugged the hole
where the cord comes trhu the wall into the house. But, I
checked with code enforcement BEFORE I did the job, and even
supplied them with a detailed schematic and load estimates. A
contractor would take care of all that.
My only regret is that I wish I'd gotten a deisel genset. We
usually get at least one 3 day outage per winter (most are less)
and keeping enough gasoline around and stored for that purpose is
kind of a hassle and requires storage planning to keep the fire
dept. happy. I checked into a large storage tank for the gas,
but that's incredibly expensive with all the codes and stuff it
has to pass: You can't just set it down and fill it, it turned
out.
So, if/when this genset bites the bullet, I'll make sure the
next one is a diesel set - fuel storage is much less dangerous.
Any further questions, just ask; I'll help where I can. I'm not
an installer, not an electrical contractor, nor any "expert":
I'm an electrical engineer and know how to read and keep up with
what the codes require is all, plus I enjoy do it yourself jobs
as a rule.
One inspector, that was out for a wiring change I made for our
foster care bedroom, laughed at the neatness of my breaker box:
I'm sort of a neat freak.
But, I can glance into it, and tell you exactly which wire
in all that mess of 40 breakrs goes to which fitting; seldom
possible with most installations. Made wiring the transfer
switch a LOT easier!
Contractors logically can't spend the time to do that sort
of thing; nothing special otherwise g.
HTH,
Pop
There are lots of links on the subject; these may help you
understand some of it:
http://www.nbmc.com/emergen/index.html
http://members.rennlist.org/warren/generator.html
http://www.money-resource-online.inf...er-switch.html
PRNole wrote:
I've been getting a lot of contradictory information from my
local
electrical contractors on my way to get an estimate for
installing a
manual transfer switch between my generator and my breaker
panel. I
need to clear the picture and hope someone can help me:
I have an off-the-rack Lowe's bought "Troy-Built" 5500W
portable
gasoline generator and want to install a transfer switch so I
can
by-pass the house's main breaker and run the generator to
supply
temporary juice when undergoing extended loss or power.
-- REasonable product, will handle furnace, fridge, lights & a
1 HP well pump per my own experience.
So far I have gotten the following advice (and prices):
1. Install a 6-circuit manual transfer switch for $600
-- Decent price, IMO IFF it includes everything from the plug
that goes into the generator to a fully functional Transfer
Switch.
2. Install the same as above for $1,200 to $1,800, depending on
what's
involved
3. Told my generator cannot work with a transfer switch
-- Unless you confused him, put this one in the round file.
What was the reason given? Totally incompetent unless there are
missing facts.
4. Told I'd be better off using a Square D Interlock kit
instead of
the 6-circuit transfer switch so I can use the entire existing
house
breaker panel and manage the load myself, not being restricted
to 6
circuits (My breaker panel is a GE and supports Square D)
-- a. 5500W isn't enough to run your entire house. You'll have
to decide what you NEED to run and go from there. You'd have to
run around each time making sure everything was turned off that
was going to overload the gennie.
With an interlock, you have no way to "sequence" the load to
the generator: ALL electric motors, etc, would come on at the
same time and probably pop the breakers (or worse) of the
generator.
b. It would still have to be a transfer switch "type" in
order to meet safety and code requirements.
c. Your local code enforcement officer can give you the best
info in this are.
5. Told *never* to use GE Interlock (or any other brand) and
stick
with manual transfer switches instead, whether 6- or more
circuits
-- Never say never, but ... a standard interlock, I don't think,
will not meet the codes and/or isn't really the right way to do
it, unless it's specifically designed to function as a transfer
switch. Besides, see my comments in your #4 above.
All the above info provided by 5 different state-certified,
licensed
contractors that operate in my local area.
-- Either there was a lot of confusion running around or you
have misheard things. I would also recommend against an
interlock, and DID opt for the transfer switch. It works well.
So, I have learned nothing except I need independent advice.
Help?