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Jonathan Barnes
 
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Default Generators and Back-up power


"Toolbert" wrote in message
s.com...

"Ryan" wrote in message
news:rjVKb.89186$6b2.6340@edtnps84...
...
So last month we bought a 7500 watt generator to make life smoother and

at
least keep the heat and lights on Here is where my question comes in.

Some
of the people around here say you can go to the breaker panel and turn

off
the main breaker (from the grid) and make a "cheater plug" to back-feed

the
breaker panel thru a 240volt outlet (of which we have several "welder"

plugs
that would be ideal for this). What are the thoughts of the group to do
something like this? I understand it is a shortcut, but if one was

sensible
about it is this a viable temporary option over the "transfer switch"

the
local electrician wants 1000 bucks to install?


As Eric writes the cheater plug works but is an easy way to kill or be
killed.

The cheapest and most useful transfer setup, IMO, is the 60 or 100 amp
single circuit style that consists of a small subpanel with a pair of
interlocked 240V breakers. Flip one off and the other on to switch from
utility to generator. The interlock prevents both from being on at the

same
time.

You use this style by installing a separate subpanel next to the main

panel
and moving the circuits you want to be "backed up" to the new panel, then
installing the manual transfer switch between the main and subpanel. You
then arent' limited by the circuit mix of the (overpriced) GenTran style
switches - like the lack of 30 amp circuits.

The attraction of the GenTran switches is you just feed this bundle of

wires
into the existing panel and make connections with wire nuts.

A pricier alternative to the interlocked-breakers switch is a "double

throw"
disconnect - looks like a regular 60 or 100 amp disconnect switch except

it
has two "on" positions. They are expensive retail but can be found on
ebay.

Bob

The other problem with the cheater plug method.... if you forget to throw
the main breaker, and the power comes back on, your 5 KVA verses the
electric companies
5 MVA is not a fair fight......
--
Jonathan

Barnes's theorem; for every foolproof device
there is a fool greater than the proof.

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