Device investigation narrative - one service replacement powermax elite motor drive unit, part number 72200616s was received on may 22, 2017 and confirmed to be serial number (b)(4).Unit was powered on using the appropriate test equipment and it failed functional tests with motor stall error and overheating when power cord was bent at strain relief.Power cord assembly grew warm during testing.After troubleshooting, the cause of error was observed to be a defective power cord assembly.A visual inspection was performed on the power cords external covering and no physical damage was observed, only cosmetic.It was determined that the power cord has a shorted or open internal wire.Motor and hall board were tested and passed functional testing.The complaint was verified and the investigation has concluded that this unit has succumbed to physical damage to the power cord assembly.Factors, unrelated to the manufacturing and design of the device which could have contributed to the reported event, include normal wear and tear, causing damage as a result of consistent use over time such as excessive tensile stress applied to the power cord, which could have partially broken one or more signal wires.Overheating is most likely associated with the short circuit in the power cord which can result in additional current delivery from the control unit and thus generate heat.No containment or corrective actions are recommended at this time.(b)(4).
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