Trying to wire my hoist, keep popping my breaker before I even get started!

I'm wiring my Bendpak 2 post and having issues. I have a 100 amp subpanel in my shop running off a 200 amp main in the house. I wired everything up on the hoist according to the manual and threads I've read on here. As soon as I flicked the 30 amp breaker I tripped the 100 amp in the house (I've never tripped the 100 amp in the shop panel yet, always the house) and the 30 amp for the hoist trips. So, I eliminated the microswitch and just hooked the two hots directly at the motor. Still blew. I then went up to the receptacle box where I've just got my 10/2 wire nutted to some 10/2 SO that runs down to the motor and disconnected all the wires. I have the two hots seperated and wire nutted off the ends and have the bare ground attached to the box. Still blows! So all I have is a 30 amp breaker with two hots hooked to it, the bare ground screwed to the ground bar, wire running up to the receptacle box with the hots capped off seperately. I don't get it. This is the first 220 breaker I've put in the panel (Eaton), I have a few 15 amp single poles running lights and a few plugs right now without issue. Could it be the 30 amp breaker? Is the subpanel wired wrong? Short in my 10/2 wire?

Does the breaker trip without any wiring hooked to it? Make sure that it is landed on 2 energized poles in the distribution panel.

Sounds like the 10/2 is bad in the middle somewhere. Disconnect from breaker and try again. Could be twisted until insulation broke or just cheap bad wire. Also if stapled down the staple could have cut insulation. One of the hot wires has to be shorted to the ground or to the other hot. Either way new wire is the only cure without adding another box and splicing it in the middle which I would not recommend.

With the 30A breaker off check for continunity between the two hots and or each hot and ground using a meter to see if there is a short in the circuit. Have you checked to see if the breaker trips with the lift not connected to the circuit? If it does you have a short in the circuit.

Edit: Sorry, I reread your post and I see that it's tripping without being connected. You have a short in the wire somewhere between the breaker and the box where you hooked up the SO cord.

10 is pretty stiff, try br without wire connected, if stays on, check you're RX in the panal and you're junc box that no copper is toughing metal. Actually pull it away and look at ALL of it, and where you're RX connectors are attached. Undo them if there metallic, may have pinched the RX.

Milton Shaw said:

Sounds like the 10/2 is bad in the middle somewhere. Disconnect from breaker and try again. Could be twisted until insulation broke or just cheap bad wire. Also if stapled down the staple could have cut insulation. One of the hot wires has to be shorted to the ground or to the other hot. Either way new wire is the only cure without adding another box and splicing it in the middle which I would not recommend.

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This is extremely unlikely. Except for the staple part.

"Bad wire" is incredibly rare. What bassman is more likely. I'll all but guaranty that this short is/was caused during installation, not manufacturing.

Thanks for the replies guys. I disconnected the wires from the breaker and it was fine so I reran some 10/2 and I now have an operational 2 post hoist.