On Mon, 12 Jul 2004 09:18:05 -0500, "Robert Swinney"
wrote:

Jake,

I'm not experienced with VFD's so I'll take a crack at your problem. (Don't
you love it when a neophyte is the first to respond) Anyway, I question why
you selected that particular VFD for your lathe. Did the manufacturer
recommend a 3hp VFD for your 3hp lathe? Are you sure you shouldn't have a
VFD of higher power than the lathe motor? The symptoms and actions you
gave seem consistent with a marginally powered VFD - But, again, I have no
experience with VFD's. Come in, Don Nichols!

Bob Swinney

Big question is...does this occur high gear or low gear, or in all
gears? As Bob said..it sounds like a marginal current starting
problem.

Im not familiar with your particular VFD, but check programming and
see if there is a min/max current setting and a min/max Voltage
setting. Its possible that its going into a brown out condition and
is shutting off as its seeing not only too much current, but too
little voltage as well. If changing accel time doesnt do
anything..check the above.

Gunner, who always puts 2 spare HP (or more) on the inverter when
specing one, particularly on gear heads.





"Jake in Escondido" wrote in message
news:tswIc.7241$i_3.2328@fed1read04...
Hello All,

I have just aquired a new to me Enco 13" lathe. The lathe itself runs
very well. But my VFD is giving me fits. About every third or fourth
time I turn the lathe on, I get a OC-C fault on my 3hp TECO 100FM VFD.
The lathe has a 3hp 3phase motor. The OC-C fault is supposed to
indicate "Overcurrent during constant speed". The causes indicated in
the manual are 1. Load changes excessively, or 2. Input voltage
fluctuates excessively. The actions are 1. Check load condition 2.
install a reactor between power supply and inverter.

The fault will occur on start up with just the 3 jaw chuck as a load.
It has never occured, once the lathe has reached running speed. I have
increased and decreased the start up time, with no effect on the
problem. The load should be pretty constant. I am not sure what a
"reactor" is.

Do any of you electronics wizards have an idea of what the problem
might be?

TIA

Jake in Escondido



That rifle hanging on the wall of the working-class flat or labourer's
cottage is the symbol of democracy. It is our job to see that it stays
there.
- George Orwell