Thanks Pete. I was going to try and search for this zig zag on Google. Sure
saves me a lot of time.
Will back off on neutral switch for the moment and check recheck all box
wiring.
I will have to translate the zig zag diagram field connections into the
specific bus bars on my genset but I think I can do that since there is a
schematic printed on a brass plate on the control panel doors.
I was thinking if that didn't work I might be better off going to
transformer configuration, but that could get expensive and still might be
tricky as I don't know how to spec the transformer.
OK on the derate. looks like 25kw. I would think that would be enough in
an emergency situation. If things get tight I have a couple of smaller sets
I use in the field to power small hand tools and motors, so I think I am ok.
"Pete C." wrote in message
...
"Pete C." wrote:
desperado wrote:
thanks for the response. I will keep looking for the wiring diagram
for the
120/240 before giving it the smoke test.
Right now, only 3 diagrams are printed on the bus bar panel.
I forgot to mention that all the neutrals of both genset and mains are
connected together. I just got thru talking to a retired electrician
and he
said that is a no no. Got to disconnect the neutral of the mains when
working off backup genset. This explains possibly why, when I did try
to
throw the transfer switch on the pumps, that the breaker in the main
panel
tripped to this particular circuit.
All equipment is still ok. I will put in a separate switch to switch
out the
neutral to the mains when on backup.
I was also worried about being unbalanced loads in each phase I am
using,
but the electrician said that wasn't a problem.
I will educate myself a bit more about transfer panel setups before
throwing any more switches and am also trying to find the service and
operator manual for this particular genset.
Thanks
--
don paolino
"EXT" wrote in message
anews.com...
Agreed. 12 lead generators can be set up in a number of 3 phase and
single
phase and voltage configurations including 120/240 volt single phase
to
match your current house system. If you can locate the wiring
diagram, it
will simplify tying into the house wiring. I have one and it is set
up
this
way.
"Pete C." wrote in message
...
desperado wrote:
I bought an old Army Corps of engineers 30kw 3 phase genset with
Hercules
DD298ER 6cyl motor.
The numbers on it say GE 5SJ4324Y2Y6
Jetta power
stock no 6115 976 8982
mfg 1964
I want to use it to back up my main power on my ranch. I have
240V
single
phase service coming in from Southern Calif. Edison.
My main panel is 100Amp single phase.
Genset has a busbar of 12 leads which can be reconfigured for
120/208
240/416 or 120volt delta .
Right now the 120/208 has been chosen. I measured 217V no load
coming
out.
There are 3big split bolt connectors coming out and one smaller
one
which
appears to be the neutral or ground. Right now, 125v is measured
from
this
point to each of the big split bolts.
I decided to use one phase to power the whole house less the
well
pumps
and put the well pumps on the second phase. That is because the
amps
per
phase is listed as only 57 amps in this configuration and I
figure I
since
the pumps take 9 amps each running and there are two of them,
that this
would leave more amps available to power the house on the other
phase.
This
leaves the third phase not connected to anything(open circuit.)
as a
spare.
I bought some transfer panels(double pole double throw) and have
brought
the well pump 30amp dp breaker wires out to a separate 60a
transfer
panel
and connected it to one of the phases of the genset. the other
phase I
put
into the 100amp main breaker and a 100 amp transfer panel.
I am a retired electrical engineer but my specialty was
microwave and
antenna design and not power engineering.
Is this setup ok or do I have to install more equipment?
If it's a 12 lead reconnectible alternator, there is a "zig zag"
configuration used to get single phase power. I don't recall the
connection sequence offhand, but you should be able to find it
online
somewhere, perhaps the Kohler or Onan sites.
Here is the "zig zag" low voltage 120/240V single phase connection
diagram for a 12 lead generator:
http://www.marathonelectric.com/gene...t/14X00903.pdf
I wouldn't worry about the solid neutral at this point, it's unlikely to
be the source of the problem and it is not always required to be
switched. The vast array of commercial transfer switch gear with solid
neutrals wouldn't exists if it was.
Pete C.
Oh yea, you also have to derate slightly when in a "zig zag"
configuration:
"You can "estimate" the Zig Zag power rating by dividing the three phase
power rating by 1.2.
i.e. 58,000 W / 1.2 = 48,333 Watts (single phase Zig Zag)"
Pete C.