An inverter problem
 

On Mon, 23 Feb 2009 14:11:47 +0000, lemelman
wrote:

Gunner Asch wrote:
On Mon, 23 Feb 2009 09:53:23 +0000, lemelman
wrote:

I'm in UK and have recently converted my lathe to variable speed by
changing the motor to 3ph and installing a Mitsubishi FR-E520S-1.5K-EC
inverter running from a 1ph 240v supply. The motor is a new Teco 2HP
unit, but the inverter was second hand.
For the first month or so, everything was fine but, out of the blue (as
it were), the inverter has been throwing out E.OV3, and sometimes, E.OV2
errors. The errors are not encountered every time the lathe is used, but
often enough to be really worrying. It happens even under no-load, ie.
the chuck is turning but there is no metal cutting at all. Originally,
the inverter fan would switch on only when the motor was turning, but
since the error conditions started, the fan is on whenever the inverter
is powered.
Any one got any ideas about this please? Could it be a problem with the
motor?


Its an over voltage condition in the regenerative dc circuit.

Double check that you have the proper value braking resistor installed,
that your supply voltage is NOT over 240vts and that you have it
properly hooked up for single phase input.

Also check your programmed motor parameters and make sure they match the
motor.

Ive not had good luck with Mitsi inverters over the years. Im a machine
tool service tech btw. Shrug.

Karl posted a link to the manual.

Gunner, who gets a OV at certain times of the day with several PC3
inverters at home...when the 1ph 220 house supply goes up to 245+
volts..and the power company wont do anything about it.


"Upon Roosevelt's death in 1945, H. L. Mencken predicted in his diary
that Roosevelt would be remembered as a great president, "maybe even
alongside Washington and Lincoln," opining that Roosevelt "had every
quality that morons esteem in their heroes.""

Thanks for the advice and pointer to the manual. I'll get a braking
resister and see what happens.


You DONT need the factory resistor btw. Just find out what the value is
(ohms) and pick up a nice big 200 watt wire wound ceramic from Ebay, the
surplus places etc) Might cost you $10 if you shop around. Or double
triple em up if you get smaller ones

Gunner

"Upon Roosevelt's death in 1945, H. L. Mencken predicted in his diary
that Roosevelt would be remembered as a great president, "maybe even
alongside Washington and Lincoln," opining that Roosevelt "had every
quality that morons esteem in their heroes.""