overload protection devices not found in a drum switch
YASMT: Allen Bradley Mag switch wiring for Single Phase
- Thread starter calgaryguy
- Start date
overload protection devices not found in a drum switch
calgaryguy
Chris
Magnetic Starters - VintageMachinery.org Knowledge Base (Wiki)
Expanation of Magnetic Motor Starters
Brent H
Ultra Member
@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
Brent H
Ultra Member
A website with electrical slang:
www.warshauer.com
Evidently confusing for electricians as well.
Electrical Slang Terms | Warshauer Electric Supply
Industry & Trade Terms and Definitions for Common Electrical Industry Slang
Evidently confusing for electricians as well.
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.
calgaryguy
Chris
@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).
Ie: @YYCHM posted a 1000 series wiring diagram which is for 220v 1ph but shows 3 wires going to the motor:
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)
calgaryguy
Chris
There is, but it doesnt apply to a reversing scenario with 3 wires coming into the motor.
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?
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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calgaryguy
Chris
240v is how I'm setup to feed this machine.
calgaryguy
Chris
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.
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.
calgaryguy
Chris
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?