Picked up 37" wide belt sander. Have wiring question.

[Matt Lackey]

331122

I got a used Grizzly sander. 15hp 3phase. It calls for. 60 amp breaker. What guage wire should I use from the box to the machine?

Matt

[David Kumm]

Sounds like there is no soft start on the machine. Are you running SOOW to a recepticle or wiring with flex to a breaker or disconnect, or hard wiring from the breaker to machine with conduit?. Machine badge itself should give you the fully loaded running amps which should be in the 35-40 range depending on the feed motor. Dave

[Chris Padilla]

15 A is #14
20 A is #12
30 A is #10
40 A is #8
50 A is #6

Those should be a good starting point. #8 is probably fine if Dave's guess on the current draw is correct.

[eugene thomas]

If calls for 60 amps would go to electric supply place and get 60 amp wire and breaker.

[jack duren]

If calls for 60 amps would go to electric supply place and get 60 amp wire and breaker.

Agree. plus call Grizzly with these questions. That's what there techs are for...

[Mike Cutler]

331122

I got a used Grizzly sander. 15hp 3phase. It calls for. 60 amp breaker. What guage wire should I use from the box to the machine?

Matt


According to Engineering Calc table, a 15 hp 3 phase motor can draw 21 amps per phase. Wiring is #10 AWG for each phase and neutral.
http://www.engineeringtoolbox.com/480-volt-motor-wiring-data-d_1447.html

Your local electrical inspector should be able to tell you the exact requirements for your location, but the above is a "rough" starting point.

[David Kumm]

Most three phase motors used in woodworking will draw20+ amps per 10 hp so close to 30 for 15 hp. Add to that the feed and possibly the bed elevation motor and you should have what the machine plate lists. With no soft start, the amp spike at start will require a larger breaker to avoid tripping. The wire gauge is dependent on type, THHN, AWG, and SOOW will all be different. If you intend to plug it in you will need something bigger than L15-30. I use a pin and sleeve on my WB. Dave

[Jeff Bartley]

Matt, I don't have any direct advise but I do have more questions! Dave, what is a 'pin and sleeve'?
And I've wondered about adding soft-starts and electric brakes to machines. Would a VFD provide a soft-start or is there another specific devise used? And would a soft-start alleviate voltage spike issues at start up and therefore be easier and safer on the system as a whole?

[David Kumm]

Pin and sleeve and Meltric are two types of plug and recepticles that handle high voltage or high amperage. So does a 50 amp four prong oven plug but that isn't what is typically used if you want to disconnect a high amp machine. You can see lots of examples on ebay. The problem with using a vfd on a wb is there are usually multiple motors and each motor needs a separate vfd. You can add a soft start module but you will find that wiring on a WB is pretty complicated. I would set up the wiring to handle the existing machine, get experience, and then decide if mods are necessary.

You can also hard wire the machine into a fusible three phase disconnect so it is easier to cut power at the machine. Fused disconnects are pretty cheap on the bay as well. Dave

[Matt Lackey]

I checked the Grizzly specs. Needs a 60 amp circuit. All I need is a plug and receptacle. Or a disconnect. Thanks for the help.

Matt