| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a protection device of an electric motor, which can improve detection precision of an abnormal temperature rise of a stator coil in the electric motor. <P>SOLUTION: A controller 44 calculates the rise temperature Tr of the stator coil 14 of the electric motor 11, based on an outside air temperature of the electric motor 11, which is detected by an outside air temperature sensor 41, and the temperature of a coil end 14a of the electric motor 11 which is detected by a coil temperature sensor 42. The controller also calculates a prescribed rise temperature Ts, corresponding to consumption current (motor load) of the electric motor 11, which is detected by a consumption current sensor 43. The controller also determines whether the rise temperature Tr is not less than the prescribed rise temperature Ts. When the rise temperature Tr is not less than the prescribed rise temperature ts is obtained, it controls an annunciator device 48 and turns on a caution alarm indicating lamp 48b. <P>COPYRIGHT: (C)2010,JPO&INPIT |
