I'm putting together a ChangFa 22hp diesel engine and a ST-10 10Kw genhead
generator set for shop power and an occasional backup power source for
Florida Hurricane season.

I would like to know what engine stats would be a good idea to monitor,
i.e. Oil pressure, oil temp, water temp, (running) hours meter (hobbs
meter), freq meter. Any others?

I am looking into setting up some kind low oil pressure or low fuel
shutdown capability but had concerns about shutting down the genset with
loads still applied to the genset.

So, an idea I had would have a high power relay inline before the panel so
when a shutdown condition was about to occurred, the relay would open up,
dropping the load from the genset then the genset would be turned off in a
safe manner.

Genset -- 240 -- relay -- fuse panel -- 120/240 circuits breakers
^
control

Any other idea on how to do this? Then genhead has a capability of 120/240
@ 87/43.5 Amps


thanks.

--
A7N8X-Deluxe, AMD XP2500+ (Un-locked)
2x256mb Crucial PC3200 DDR ram
Palit-Daytona Ti4200/64M AGP

"SomeBody" wrote in message
news

I am looking into setting up some kind low oil pressure or low fuel
shutdown capability but had concerns about shutting down the genset with
loads still applied to the genset.

So, an idea I had would have a high power relay inline before the panel so
when a shutdown condition was about to occurred, the relay would open up,
dropping the load from the genset then the genset would be turned off in a
safe manner.

Genset -- 240 -- relay -- fuse panel -- 120/240 circuits breakers
^
control



My thoughts are if you are shutting down on low oil, you need it off right
now!
I work on standyby generators. None of the units I work on shut down the
generator before the engine on a fault of any kind. The controls just kill
the engine immediately.
I think you are over engineering something. Keep it simple.
Greg

On Thu, 02 Jun 2005 21:46:52 -0500, Greg O wrote:


"SomeBody" wrote in message
news

I am looking into setting up some kind low oil pressure or low fuel
shutdown capability but had concerns about shutting down the genset with
loads still applied to the genset.

So, an idea I had would have a high power relay inline before the panel so
when a shutdown condition was about to occurred, the relay would open up,
dropping the load from the genset then the genset would be turned off in a
safe manner.

Genset -- 240 -- relay -- fuse panel -- 120/240 circuits breakers
^
control



My thoughts are if you are shutting down on low oil, you need it off right
now!
I work on standyby generators. None of the units I work on shut down the
generator before the engine on a fault of any kind. The controls just kill
the engine immediately.
I think you are over engineering something. Keep it simple.
Greg

Thanks for your input, the old saying K.I.S.S, you are correct.

My thinking was that I have a well (water) that would need to be run when
power is out due to storm or ???, I've heard that if your genset stop
running while the well pump is runnng, you risk tearing up the well pump,
(how? not sure), which is about 300-400 ft underground, expensive to fix
or replace!

If my engine gets to a point of low oil pressure, you are correct,
shutdown now! To recharge the winding, due to demagnatizing, when loads
are on the genset and engine stops, battery charger and turn the engine
over a few time, I'm guessing here on the procedure and the terminology
here, so bear with me.

These were my concern, mostly my well getting damaged somehow, I would
have to explain to the wife how that happened, if this is the case, Not a
fun thing to do!

Thanks

--
A7N8X-Deluxe, AMD XP2500+ (Un-locked)
2x256mb Crucial PC3200 DDR ram
Palit-Daytona Ti4200/64M AGP

On Fri, 03 Jun 2005 03:52:29 GMT, SomeBody
wrote:

Thanks for your input, the old saying K.I.S.S, you are correct.

My thinking was that I have a well (water) that would need to be run when
power is out due to storm or ???, I've heard that if your genset stop
running while the well pump is runnng, you risk tearing up the well pump,
(how? not sure), which is about 300-400 ft underground, expensive to fix
or replace!

Having the power die while the well is running will not hurt the
submersible pump.

A close lightning strike or other large voltage surge (well above
the motor operating voltage) sure will, though, so make sure the
wellhead control box has the biggest lightning arrestor you can get,
to try and dump the surge to ground before it goes down the cable.

If my engine gets to a point of low oil pressure, you are correct,
shutdown now! To recharge the winding, due to demagnatizing, when loads
are on the genset and engine stops, battery charger and turn the engine
over a few time, I'm guessing here on the procedure and the terminology
here, so bear with me.

On modern design alternators you should never have to worry about
'flashing the field' to get them to output power. There is enough
residual magnetism to get them started, unless it's been sitting for
20 years.

Even on my 60-year old AC Generator (good-old brush type), I've
never had to flash the field on the main exciter or main generator
windings, worst has been waiting a few seconds for the brushes to bed
through the oxide a bit before the 120V output pops up...

But the stupid little Delco-Remy 12V generator on the engine, that
one is a major pain in the butt every time. I just take a 120V
battery charger with me and run it off the main generator, which is
enough to power the ignition system - till I get around to adapting a
modern 12V alternator on there.

And as for emergency shutdown, you have a few choices. If you will
be starting the powerplant manually, the simple method is the good old
Murphy Switchgauge - it's a set of panel gauges (temperature or
pressure) with a contact that the gauge arm hits - simple and
reliable. If the oil pressure falls, or the water temp rises, the
gauge hits the contact, trips a relay, and kills the ignition. Just
about foolproof.

But you have to manually reset the relay and bypass the oil gauge
trip during starting, so automatic control is out.

For automatic starting, you use standard automotive "idiot light"
senders for the signal inputs, and come up with a time delay to allow
time for the oil pressure to build before activating that sender in
the kill-switch circuit.

-- Bruce --

--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.

"SomeBody" wrote in message
news
To recharge the winding, due to demagnatizing, when loads
are on the genset and engine stops, battery charger and turn the engine
over a few time, I'm guessing here on the procedure and the terminology

I have a very old Dayton genset from the early 1960s. It's the older, more
robust (but more complicated) rotating wound field, wound stator, as opposed
to the newer rotating PM stator designs.

When we first dug it out of the Civil Defense bomb shelter we were
de-commissioning, it was in sad shape. It didn't take too long to get the
motor running, but even when it ran, and even when the slip rings and
brushes were clean, it produced only a couple of volts AC at no-load, and
zero into a load.

So we pulled the slip ring end spider and bearing, and tightly clamped some
heavy copper wire around the slip rings with hose clamps (to serve as
terminals that wouldn't mess up the slip rings). Then we "rang" it with
36VDC from a DC welder. Basically, we just drew and broke an arc to the
wire terminals.

It generated after that. There doesn't have to be _much_ residual magnetism
in the field... just enough to get it to "self excite". After that, it
generates its own field current, and tends to get better with more run time.

LLoyd