View Full Version : Reversing a motor

05-08-2009, 10:54 PM
Hi guys. I have been reading all the posts on motor reversing and I am still stumped. First off I know about as much about electric motors as I do Big Foot. Here is what I have. Craftex B1977 Mill Drill with a Jui Chun 1 1/2 hp motor. The motor is wired for 220v and is a 4 pole single phase. 60 hz, Class A . 1725 rpm. No: J02402 Capacitor start. 22/11 amp and It can also wire up for 115 v and has a reset switch. There are 6 wires coming out of the motor, 4 black numbered 1 2 3 4, then there is a white wire from the capacitor number 5 and a red wire from capacitor number 6. Wires 4 & 6 black and red are together. Wires 3.5.1. are together black, black,white. then there is a black wire #2 .

Motor .................................................. To switch "Toggle"
B&R No:4 & 6.................. 0 ---------- 0 Black wire no number going to otherside of reset switch

B B W No: 3 5 1.............. 0 -------- 0 Blank

Black wire no number....... 0 ------ 0 White
Going to one side of reset

Black wire # 2................. 0 ------ 0 Black

I would like to try and wire this up to a drum switch to get reverse. Can use some help here guys. Thanks ... Fred ............ Also what make of switch would you recommend I get. I was thinking a Square D..

J Tiers
05-08-2009, 11:03 PM
You may want to do this yourself, or, if you really don't have the background, and don't have an ohm-meter, etc, you may want to have someone else more electrically-minded, or an electrician, do the job. I am providing the info but I am obviously in no position to guarantee the work.......

OK, the chop suey motor has completely different lead numbering from a NEMA motor..... but.......

normal 1 phase motor wiring.. you want the lower one


typical drum switch:


The reset is the "thermal" in pic 1, put in series with the motor input. It must cut off BOTH the start AND the run windings when open.

In any case, the drum switch has connections between 6 terminals, typically. In one position (forward) it connets straight thru. In the other (reverse) it reverses two wires.

You want it to re-connect the start winding in the reverse polarity to reverse, so that the motor starts in the opposite direction. So you will use the reversing contacts to do that.

The remaining contact will be your power switch.

It may be that the drum switch you get will have the "reversing" terminals at the bottom instead of the top. It makes no difference to operation, but it obviously affects the way you wire it. So you need to know which terminals are the "reversing" ones when you go to wire the switch.

Some folks will probably immediately jump up and breathlessly explain that the power switch must disconnect all the hot wires... Don't worry about that. it is a power switch. You will need a real "disconnect" (which can be your power cord and plug), to remove power positively when you want to do maintenance on teh machine.

05-08-2009, 11:13 PM
Thanks J Tiers. I will study this. I dont have a black wire numbered 8 ?? There are only 4 black wires numbered 1234 1 white and 1 red coming from the capacitor.

05-09-2009, 03:57 PM
Don't seem to be able to find any information on the net for this motor to tell me what wires are what.

05-10-2009, 02:01 AM
You may have a non reversable motor. Meaning that the start winding leads are buried inside.

Its possible (usually) to open it up and splice some wire on and lead them out to the connection box. There is usually very little space for a wire connector, so solder and heat shrink tubing may be necessary, and a lot of care to prevent damaging the windings.

The Harbor Freight $99. compressor motors are one example.
They are made to run counter clockwise and are sold as "non reversible".
That didn't stop me from reversing one for one of my compressors.
However, I didn't bring the leads out, as I don't need to reverse it in use.
It now runs clockwise.

05-10-2009, 12:48 PM
As usual, Busy Bee does not have any documentation on-line.

Grizzly has a similar type of mill (http://www.grizzlyindustrial.com/images/manuals/g1007_m.pdf) On page 37 they say to reverse the location of wire 5 and 6. Maybe some of the electrical guys could advise.

J Tiers
05-10-2009, 02:41 PM
If both wires come from the capacitor, it may be non-reversible (without digging). That is, if one wire goes to the cap from somewhere external, and the other disappears into the motor, you may not have the other end of the start winding available..