Delta 20" 3ph bandsaw quit...

[Don Buck]

I have a Delta 28-641 230 v 3 ph model running via a 5 hp rotary phase converter. I purchased the saw last year (high school shop closure) and have used it about 30 minutes total over the past 6 months. I started up the saw last night and it came up to full speed for about 7 seconds and then stopped (motor stopped and saw coasted down to a stop). The phase converter never stopped. I checked the 230 3 phase breaker (did not trip but reset just in case) and the 3 slow burn fuses in the disconnect (all three were fine but I replaced them with new fuses). The wiring at the box (both wall and to the saw) were fine, no loose wires, not burnt spots).

Before I get out my meter and start checking circuits, is anyone aware of a reset button on the Delta 20" bandsaw? I called both the local Delta service center and the main office and they were not familar with the saw (you would think Delta would know their own tools!).

Any suggestions would be greatly appreciated.

Motor is 2 hp, 60 hz, Class E, 5.8 amps @ 230 volts.

Don

[george wilson]

Sometimes dust can get into the off/on switch and make trouble. I had a 20" Delta at work,and I think twice over the years,I had to get maintenance to fix the switch. Try blowing it out with compressed air.

There may be a reset button on the motor itself. It might be hard to see/find inside the saw's cabinet. Feel around for it.

[Chip Lindley]

Don, IF cleaning out the on/off pushbutton fixes your problem, all is well.

Just in case, the "reset' on 3-phase motors is in inside the magnetic starter enclosure. 3-ph motors, themselves, do not have a reset as single-phase motors do. Download a copy of the Delta LVC Manual here for the most complete info available.

http://media.ptg-online.com/media/dm/OwnersManuals/20040331153155_En438-01-655-0002-04-01-04.pdf (http://media.ptg-online.com/media/dm/OwnersManuals/20040331153155_En438-01-655-0002-04-01-04.pdf)

Check the fuse on the low voltage transformer inside the starter enclosure. It may have blown. Look at that first.

Check that motor connections are set up the same as the input from your rotary coverter; 230v. The saw may have been set up for 208v (available at many schools) Connections to the LVC transformer will be a dead giveaway. Doubtful, but the saw may have been set up to run on high voltage. (460v)

Delta starters used GE "C-series" or Furnas "E-series" heaters. There should be a chart inside the starter enclosure cover for the heater to match your motor's amperage.

Check all that and let us know what the verdict is.
~Chip~

[Larry Edgerton]

I have the same saw and am tossing the idea around of installing a single phase motor so I don't have to run the phase converter every time I use it. Same deal, I got it from a folded school shop program.

On the other hand, I would like to get rid of my 50 hp converter and get one of the new electronic converters I have been reading about on here. No converter noise would be awesome!

Post what you find in case I have a similar problem, thanks.

[Jeff Duncan]

I had an intermittent problem with my late model 20" and it ended up being a loose wire inside a junction box between the motor and disconnect. Not sure how old your saw is, but the newer ones have a overload thingy on the back of the switch. I spent hours on that thing before I eventually found the real problem:(

good luck,
JeffD

[Don Buck]

(I'm the original poster)
I also found a loose wire on the junction box (the one attached on the motor). However, tightening the nut didn't fix the problem. Currently I'm trying to figure out if I have a bad ON/OFF switch.

Don