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YASMT: Allen Bradley Mag switch wiring for Single Phase

@YYCHM : I had never heard of the thermal overloads referred to as heaters - mind you, I am not in the shore side electrical business but “overload”, “trip”, thermal protection, thermal etc etc, absolutely- took me a bit to figure out what was going down. You really do not want “heat” so I guess it is the same as calling an electrician a “sparky”. Pretty undesirable- LOL
 
Sorry for the slang term. It does describe their mode of operation very accurately: a resistive coil of wire heats up based on current flow which then opens a by-metallic switch and thus interrupts the circuit causing the contactor to unlatch. This is what protects the motor from overload. The “heaters” (the resistance wire) is sized based on allowable current of the load. Works very well. And yes, they do get hot and glow as the max protection current is flowing through them.
 
RobinHood said:
View attachment 21977
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@RobinHood, if I disregard L2/T2 (which is what my AB mag switch inside cover diagram/instructions says to do also) to use 1 phase power, does the motor not need a line voltage input?
( I should add that my AB inside cover additonally says to 'disconnect 'X2' from L2 and run it to L3 which I have done - its a small gauge wire that runs from the right side of the coil).
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Ie: @YYCHM posted a 1000 series wiring diagram which is for 220v 1ph but shows 3 wires going to the motor:
110wiring.JPG

This ^^ diagram shows a lead that runs from T1 to position 4 on the reverser switch and from postion 4 on the reverser to one line on the motor, or simply a line from T1 to a line on the motor.

Does that make sense? If so, how do I wire my motor leads to accomodate these 3 connected lines? Im in a little over my head how to wire my motor leads

Heres the wiring diagram for my Baldor L3507 (which is reversible)

baldor-wiring.PNG
 
Is there a wiring diagram on the motor itself? Some times it's on the back side of the connection box cover plate.
 
There is, but it doesnt apply to a reversing scenario with 3 wires coming into the motor.

1647378191703.png


I've wired dozens of 1ph 220v motors with mag switches before, just never with a reverser and a on/off switch remote from the mag switch.


It would seem to me that the lead from the T1 terminal on the mag switch needs to be connected to both position 4 on the reverser and to wire 1 on my baldor motor (either in series or in parallel). Then a lead from position 2 on the reverser switch to wires 4+5 on the motor, and finally a lead from position 3 on the reverser to wires 2+3+8 on the motor. Does that make sense?
 
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I think my above wires be correct for what your doing? Select direction and push the button - might need to see which way FWD and REV is
 
Maybe I dont fully understand but are you suggesting that there should be 5 separate lines connected to the motor? If so, that doesnt sound right.
 
I concur with @Brent H ’s diagrams and comment about possibly having to switch out motor leads 5 and 8 if the direction of rotation is opposite from what you need to match the F/N/R lever position.
 
Well, you can take the two wires at switch connection 2. (Wires to motor 2/3) and just run 1 to the motor with a jumper across 2/3

You will have a few wires going to the motor if you want reverse.
 
calgaryguy said:
Maybe I dont fully understand but are you suggesting that there should be 5 separate lines connected to the motor? If so, that doesnt sound right.
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Yes. You are letting the F/N/R switch on the panel do the connecting of the correct wires in order to control the motor‘s direction of rotation AND cause it to drop off line if you happen to move the switch while the motor is running.
 
@Brent H and I posted at the same time: Brent’s comment in post #36 is a more elegant solution and reduces the wire count by one. Go with that.
 
Brent H said:
Well, you can take the two wires at switch connection 2. (Wires to motor 2/3) and just run 1 to the motor with a jumper across 2/3

You will have a few wires going to the motor if you want reverse.
Click to expand...
So thats

T2 (t3 in my case) to motor 1
Reverser switch 1 to motor 8
Reverser switch 2 to motor 2+3
T1 to reverser switch 3 to motor 4
Reverser switch 4 to motor 5

So 5 leads in total to the motor?
 
That's pretty much what I had to do on my lathe. 6 leads if you want to run a ground through.
 
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