wiring up a grinder motor.... couple quick questions

S

SkaerE

Joined
Sep 9, 2001
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bought a motor from surpuscenter.com and i assumed it had the proper switch and all included... but it doesnt. I cant seem to get anyone on the phone to help me out, so maybe you guys can?

motorplate.jpg


this is the plate on the side.

my questions:

1.) what kind of switch do i need to buy to run it off a 220 plug? i ideally a forward, reverse, off switch would be nice... but not necessary

2.) looking at the "high volt" wiring diagram... INS means insulate? as in wire the listed wires together and insulate them from everything else (wire nut or similar)

thanks!!
 
You are correct in that INS means to connect together and insulate. I don't think I can post pics here, but I'll try to explain the switch wiring for a reversing switch.
You will need a double pole double throw (DPDT) switch. Make sure it is rated for the 20 amps the motor is rated for. This will have six connections. Black and red will each go to the center poles. Wire jumpers from the outside corners to the opposite outside corner and leave a long pig tail off of the two corners. To clarify, two corners on one end will have 2 wires on them, One of which goes to the corner on the opposite side, the other will connect to the motor wiring where the black and red wires were shown to be connected. If you can understand all that, I congratulate you !
This same configuration can be used to reverse 3-phase motors as well.
 
oops, forgot the power switch. This can be done with a singlepole/single throw (spst) if you are wiring for 110V. These have just 2 connections. Bring the Black (hot power wire) to one connector and connect Line 1 from the motor to the other connectior.
For 220 volt, both power wires are hot, therefore you will need a double pole single throw (DPST). Wire the power to one set of poles and Lines 1&2 to the other set of poles.
There really is no reason you can't use this same configuration for 110V. There is no need to break the nuetral line, but nothing says you can't either. Having the double pole switch in place gives you the option to rewire for 220V at any given time. Personally, that's what I'd do.
 
Not sure what you're implying. If you mean useing that kind of switch as a combo on/off fwd/rev, It might work, but your not killing the power to the line leads which may leave the winding of the motor energized but without movement, it may damage the motor.
 
Post 2 applies to the fwd/rev switching only. It assumes you have pwr on the motor via lines 1 & 2. Not seeing a wiring diagram of the actual windings, I wouldn't gamble that disconnecting the directional wiring ( red and black ) will remove power from all windings. Better safe than sorry.
 
Ahh, I think I get it now.

You aren't actually flipping L1 and L2 with the DPDT, but T5 and T8?

See why I am not an electrician?
 
Gotcha, I was thinking you just reversed L1 and L2 to reverse rotation.

Color coding had me twisted up....

So then we would need a 3PDT switch if we wanted an all in one power and reversing switch...
 
Just to throw a few other ideas into the pot:

Consider a reversing drum switch. I would use a 30-40 amp switch like these ones. It makes the whole wiring job easier and the switch is made for this exact task.
http://shop.ebay.com/i.html?_nkw=re...+switch&_osacat=0&_trksid=p3286.c0.m270.l1313

A second way to wire a large motor is a motor start switch/motor control switch. They are made to take the load of making and breaking the circuit without arcing out. A simple DPDT switch will not last long as a reversing switch.
http://www.ebay.com/itm/NEW-Motors-...268?pt=LH_DefaultDomain_0&hash=item3cbae056fc
 
excellent, so the switch i saw at Grainger (spec below since my link didnt work) should work great?

Drum Reversing Switch, Power Rating @ 230 VAC Single Phase 2 HP, Power Rating @ 115 VAC Single Phase 1 1/2 HP, Power Rating @ 230 VDC 1/4 HP, Length 4 1/2 Inches, Depth 4 Inches, Width 2 1/4 Inches, Reversing
Grainger Item # 2X440
Price (ea.) $57.05
 
Yes a drum reversing switch has the reversed wires already wired in. You hook up the power in and motor out and it is done. No double wires and such to get wrong or come loose.

The basic concept is the outer poles are connected to each other in an "X". The inner poles ( common) are where the power comes in. The motor goes to one set of the outer poles. Throw the switch one way and it runs CW, toss it the other and it runs CCW. Leave it in the middle and it is OFF. I would put a master switch in the power line as a safety feature. Things like drum switch arms get bumped too easily.
 
IMG_9764.jpg


ok, this is the switch i ended up getting but unfortunately i cant for the life of me figure how to wire it to my motor.

if someone can give me some specific "which wires from my specific motor go where" instructions I would greatly appreciate it! :)

thanks
 
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