VFD braking part duex

Call Hitachi and cry on their shoulder. Perhaps they will take pity and tell you the secret code to get the VFD to use the resistor. Or tell you that your case is beyond hope.

I've got a SJ100 with braking resistor driving the Clausing 5914, and it is not obvious that the braking resistor makes any difference. I have not got around to measuring the voltage across the resistor. I didn't notice the B90 parameter in the manual, so I'll have to look into that.

Joe Gwinn

If all fails, you can buy a 5 HP drive from me, with a brake resistor. (that is 5 HP 3 phase, needs to be derated for single phase).

$100 if you want one in a not so good cosmetic condition (cracked front cover).

I will give you one year right of return, but you pay all shipping.

I reduced stop time from 9 seconds to .4 seconds on my CHNC lathe with the SJ100

Karl

Very fair, but I need to drive a 5hp. from single phase.

Karl

Are you decelerating hard enough and with a big enough workpiece to cause the VFD to dump excess voltage to the resistor?

Just checking...

Mark Rand RTFM

Yes, looks like you need something bigger.

Same here, about the same reduction on my Bridgeport, when I installed a suitable brake resistor. It feels like "instant soft stop".

That pretty well cinches it - you don't need fancy instruments to tell

So I looked - B90 was set to zero, the default, which disables dynamic braking. Set to 100.0%, and set the deacceleration time F03 to 1.0 seconds. What a difference.

I always suspected that I had a settings problem, but never got round to figuring it out. This was the clue.

Joe Gwinn

For the record, I have a 50 Ohm braking resistor, and the 5914 has a 2 HP motor.

Yep, I'm trying to reduce decel time F003. If i go below 10 seconds the drive KOs code 7 which is bus overvolt.

Karl

Check B095 (dynamic braking control)

The USA default value is 00 (off) (page 3-39 of the manual you linked to)

The other values are 01 (enable during RUN only) and 02 (enable always).

BINGO!!!

THANKS A BUNCH. Set stop time to 2 seconds, I'll play more tommorrow.

karl