[How do I?] wire forward-reverse switch

tjb

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Hello, All.

I have received some very helpful responses from several of you on an older lathe I acquired similar to a Jet 1024 (Kin Shin Model KS3.5FK, 1976 model). Thanks.

I'm down to (hopefully) one more issue before this machine is operational. I bought a new Leeson motor that I have wired for 220. The machine's original SUPPLY or IN cable was cut too short to use. It had three wires: red/black/green, which I have replaced with one that has white/black/green (you'll notice in the picture I colored the white with a red sharpie so that the three colors match the original). The red and black are wired into the switch and the green is grounded to the machine.
I am still using the original SWITCH or OUT bundle of four wires: red/white/blue/green - all of which are unchanged from their original positions in the switch. Below are some pictures of all this, including a photo of my handwritten info contained on the face of the switch and the exact wiring pattern before any changes (you can't really tell from the photo, but the circle of terminals are stamped in the plastic as A-1-2-B-3-4, reading clockwise).

I'm certain the motor works correctly because I first wired it directly to the SUPPLY/IN line - it hums like a sewing machine. However, when I wire into the switch then through the SWITCH/OUT line to the motor, it kicks the breaker. I have not changed any wiring in the switch other than exactly matching the IN wires.

I assumed the old OUT 'red' and 'black' to be the live lines, and the 'green' to be ground. That's how I wired them to the motor. Don't know if I'm doing something wrong or if the OUT wiring somehow got crossed before I got the machine.

Anybody have any familiarity with this issue and/or this switch in particular?

Thanks,
Terry

IMG_1229.JPG IMG_1233.JPG IMG_1234.JPG
 
Terry: First rule is not to assume anything. If it doesn't work now and you haven't changed anything then it was miswired when you got it.
We will need some more info on the motor and switch. Do you have a multi meter or some way of checking continuity (even a battery and light bulb would do)?
That switch is different than most so you will most likely need to "ohm it out"
Mark S.
ps it looks like the problem might involve the green wire- if it's ground it should not be a switched wire
 
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I had one of these switches on an Atlas TH42 lathe.

something to establish is whether the motor is going to be running on AC or DC before we can answer any control questions

the ground connection should not be made or broken by the switch, it should be connected to the motor frame.
you should only be switching power poles

How many leads come out of the motor?
 
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What type of motor? Can you post a photo of the wiring plate on the motor? Most reversible motors do so by interchanging leads to a terminal block within the motor. To change directions with an external switch, you have to bring those leads outside the motor. I believe that you should have at least four wires plus ground. Two for the main winding and two for the start winding and ground.
 
I had one of these switches on an Atlas TH42 lathe.

something to establish is whether the motor is going to be running on AC or DC before we can answer any control questions

the ground connection should not be made or broken by the switch, it should be connected to the motor frame.
you should only be switching power poles

How many leads come out of the motor?
 
Thanks for your reply, Mike.

The motor will be running 220 AC. I think you may have hit on the reason underlying the problem. If you refer back to my handwritten schematic, position 'A' is the green wire that goes OUT of the switch and to the motor. If I'm understanding you correctly, it sounds like that should not be wired to any terminal on the switch. I assumed the other end of that wire should have been grounded to the motor frame.

Attached is a photo of the spec plate on the motor. I am wired exactly like the 'High Voltage' schematic shown in the lower left section. My 'Red-OUT' (position 4 about 9:00) corresponds to Leeson's 'L1' which connects to 'P1'. My 'White-OUT' (position B about 5:00) corresponds to Leeson's 'L2', connecting to 'T4/T5'. As noted above, my 'Green-OUT' (position A about 10:00) is grounded to the motor frame. I have 'Blue-OUT' (position 2 about 3:00) capped off. (I tried the Blue and capping off the White with the same results.) As Leeson's spec plate shows, P2 is a capped dead-end, and 'T3/T8/T2' is wired together and a dead-end. (Again, keep in mind all the OUT wires on the switch are unchanged from how it was wired when I received it.)

If I'm beginning to understand this correctly, it sounds to me like I should do the following:
1. disconnect the 'Green-OUT' from position A and attach it to a convenient spot on the lathe housing;
2. isolate T5 and connect it to my 'White-OUT' (position B);
3. isolate T8 and connect it to my 'Blue-Out' (position 2).
If the directions are backward from the switch, I reverse the White and Blue wires.

Steps 2 and 3, of course, assume those are in their correct positions on the switch.

Sound right?

Terry


P1000093.JPG
 
What type of motor? Can you post a photo of the wiring plate on the motor? Most reversible motors do so by interchanging leads to a terminal block within the motor. To change directions with an external switch, you have to bring those leads outside the motor. I believe that you should have at least four wires plus ground. Two for the main winding and two for the start winding and ground.
 
RJ,

Thanks for your response. I just posted a response to Ulma Doctor which I think includes a response to you as well. If I knew how to do it, I'd copy and paste here, so if you are not able to read my answer to him, let me know, and I'll give you more detail. For safety's sake, I'm re-attaching the spec plate off the Leeson motor I'm using. I 'think' I understand what to do next, but I'd very much like to hear your comments on my post to Ulma Doctor. Again, if that's cumbersome, I'll send you more detail.

Thanks again for responding. I think we're almost there.

Terry
P1000093.JPG
 
if you want directional control over the motor,
essentially you'll be alternately switching T5 & T8 to make contact with T4/line connection as well as the T2 and T3 pairing
P1 will get a line connection and can be switched if desired.
P2 is capped off
T2 and T3 are going to need a jumper wire extended to the switch to then be switched with T5 or T8 respectively at the switch connection

if you are not interested in forward and reverse, the problem can be handled differently
 
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Terry: First rule is not to assume anything. If it doesn't work now and you haven't changed anything then it was miswired when you got it.
We will need some more info on the motor and switch. Do you have a multi meter or some way of checking continuity (even a battery and light bulb would do)?
That switch is different than most so you will most likely need to "ohm it out"
Mark S.
ps it looks like the problem might involve the green wire- if it's ground it should not be a switched wire

Thanks, Mark.

I'm working 'uphill' on responses, so I'm only just now getting to yours. I used an ohm meter to test continuity on both Forward and Reverse. Good news: I got a lotta continuity! Bad news: Totally unsure of what I should have gotten. However, I think you might be zeroing in on something Ulma Doctor noted. I have assumed the green wire coming out of the switch (position A about 10:00 on my schematic) was a ground, so I grounded it to my motor frame on the motor end. Sounds like that's not the case. Can you access my answer to Mike (Ulma Doctor)? If so, could you share an opinion on what sounds like a solution?

Regards,
Terry

P.S.: Just in case, here's another copy of the motor spec plate.
P1000093.JPG
 
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