CSA File No. Proof UL File No. CSA File No. Motors come with either sleeve bearings, ball bearings, or roller bearings. Sleeve bearings are more economical and quieter than ball.
Ball bearings carry heavier loads and can withstand more severe applications.
Roller bearings are used in large motors for belted loads. Belting data must be provided on all belted applications. For shaft up applications, contact your Marathon Electric Sales Engineer, Representative, or local Marathon Electric Distributor. Marathon Electric inverter-duty motors are rated for continuous operation in a 40 degree C ambient and altitudes up to 3300 feet above sea level. Variable torque ratings are suitable for operation from 0 to base speed.