If you really have an overhead crane to install it would also be likely that you would either know how to do the installation already or would know that such work should only be done by a licensed electrician...
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It would be easier to give you a more helpful answer than this one if you had described the crane and the size of its motors. You need to give such basic details as the output horsepower of the electric motors used to turn the crane and lift the load, their operating voltages and current consumptions...
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This seems like a question from an electrical course, and is probably best answered by referring to your course materials.
It's your test question, not ours, and there won't always be someone else to ask for the answer.
Earn your diploma.