Originally Posted by
David Kumm
This thread teaches a lesson when buying machinery. Motors are an area where there is a lot of cost cutting. Smaller frame with lots of wire ( good insulation allows this ) allows for lighter weight, less strength to base and guts of machine. Smaller shaft and bearings, etc. The problem is that these motors run hotter, as do the bearings so it is important to look at the motor as more of a temporary part than a forever one. Means you must check that it can be either readily replaced, has a standard frame, has HP (kw ) appropriate for a standard replacement. There are 90 frame metric motors in machines that provide 10 hp but try to find a replacement over 5.5. If the motor isn't standard or high hp for the frame size, can it be rewound reasonably? Motor guys hate packing lots of wires into a small frame or rewinding a small diameter long body motor and the cost go up exponentially. If you are forced to buy a replacement from the machine company, you are doomed. If sales people can't give you the origin, frame size, bearing size, and efficiency, find a sales guy who can. If we don't ask and expect answers for slightly more technical questions, we will be responsible for the reduced quality. Dave