Advice for wiring

[albrechtmyers]

Hey guys, I am looking at a job that has a 200 hp motor on top of a 200 foot grain leg. I have never had to pull wires vertically that size. Does anybody have any experience or tips for this? I was wondering if it would make sense to start looking for some kind of a busway system instead of trying to pull wires up there? If wire pulling is an option what kind of tugger and what kind of wire supports would I need? Also would you use a vfd or a soft start? I don't think the cost will sway a decision one way or another, but which one is better for the application?

 

[LarryFine]

You'll need conductor supports, but here's the best advice: it's easier to pull wire down than up.

 

[infinity]

What's the voltage and what size conductors are you planning on using? Will it be necessary to run the motor at a reduced speed? If so then a VFD might be the way to go.

 

[ptonsparky]

If I had the choice it would be a VFD. Changing or repairing the buckets on that belt will be a lot easier if you can vary the speed.
Other than that, the belt needs to run at speed to empty the buckets properly.

 

[albrechtmyers]

figured out. thanks to all.

 

[ptonsparky]

figured out. thanks to all.

Oh no. Not so easy. What did you decide?

 

[kwired]

You'll need conductor supports, but here's the best advice: it's easier to pull wire down than up.

Never done a 200 HP leg, but yes if you feed from the top, the task eventually becomes how to hold the conductors from falling all the way in instead of how to pull them up, even if they are just 12 AWG conductors being installed.

 

[reast]

Use conductor supports, and don't use LB's at the top, use elbows or sweeps if you need to make an angle. LB's have edges sharp enough that if the wire is pulling from a lot of weight, it can cut through the insulation.

 

[don_resqcapt19]

See 300.19 for required conductor support for the vertical conductors.