Under the red cover is a SPST switch that switches the mains voltage to the transformer primary.
The transformer is 24V center-tapped. A bride rectifier sits across the secondary, yielding +/- 12V with respect to the center tap (CT). The CT is wired directly to one side of the motor. The other switch is a momentary SPDT that connects the other side of the motor to the + or - side of the bridge.
@bdsargent The transformer is mounted to an weatherproof 2-gang junction box, with holes drilled in the cover for the wires and mounting screws. Inside the box are a couple terminal strips and four high-current diodes soldered together to create the bridge rectifier.
The switches are in a single-gang weatherproof box. The two cables between transformer box and switch box are 3-conductor 14-gauge SO cable; one for mains power and one for the +/- 12V switch.
I believe I got it from mpja.com. They deal in surplus stock, and it doesn't look like they have it any more. Any high-torque worm-drive reversible motor will do. Be aware that some worm drives can be driven by the output shaft, so you may need to rig some sort of locking mechanism.
I'm inspired. How did you construct the switch and controller?
bdsargent 5 months ago
@bdsargent Here's a basic description:
Under the red cover is a SPST switch that switches the mains voltage to the transformer primary.
The transformer is 24V center-tapped. A bride rectifier sits across the secondary, yielding +/- 12V with respect to the center tap (CT). The CT is wired directly to one side of the motor. The other switch is a momentary SPDT that connects the other side of the motor to the + or - side of the bridge.
Lotharyx 5 months ago
@bdsargent The transformer is mounted to an weatherproof 2-gang junction box, with holes drilled in the cover for the wires and mounting screws. Inside the box are a couple terminal strips and four high-current diodes soldered together to create the bridge rectifier.
The switches are in a single-gang weatherproof box. The two cables between transformer box and switch box are 3-conductor 14-gauge SO cable; one for mains power and one for the +/- 12V switch.
Lotharyx 5 months ago
I just bought that hoist... where did you buy the motor?
rakishi18 1 year ago
@rakishi18
I believe I got it from mpja.com. They deal in surplus stock, and it doesn't look like they have it any more. Any high-torque worm-drive reversible motor will do. Be aware that some worm drives can be driven by the output shaft, so you may need to rig some sort of locking mechanism.
Lotharyx 1 year ago