DC motor is not a long time, enabled again will find motor winding insulation resistance is reduced, especially in the rainy season, the air humidity is big, the insulation value even reduced to zero, then it should be dried and so that the insulation resistance and absorption ratio reaches the specified value, here we introduce some kinds of methods dry:
Drying method of electric welding machine
1, AC welder before drying operation will damp winding gear motor wiring head series, chassis grounding, so that it can be of three groups of windings for heating and drying, current monitoring changes in the drying process, can be strung into a current meter, observe whether its current reaches the rated current of the motor. The DC motor is dried by an alternating current welding machine without disassembling it to reduce the work load. At the same time, the motor is heated by its own resistance under the condition of power supply, so that the coil is evenly heated and the drying effect is better.
2, DC welding machine drying operation wiring and AC similar, the series ammeter should be DC ammeter. It is easy to use the DC electric welding machine to damp and decelerate the motor, and it can be used for the long time drying of the large and medium-sized decelerating motors and the high voltage decelerating motors. In this way, when the welding machine works for a long time or a large current, its internal components will not be damaged by long time high current work, so it can be used for large and medium-sized deceleration motors for a long time. It is worth noting that when the two methods are used for drying, all contact points must be contacted well and tightened. The wire of the welding machine should use special wire, and the size of the cross section should meet the current carrying capacity of the welding machine. Pay attention to the cooling of the transformer itself and ensure the insulation resistance of the reducer motor can not be lower than 0.1M ohm. Pay close attention to the winding temperature of the reducer motor and adjust the voltage and current in time.
Two. External heat source heating method
For damp DC decelerating motor, it is disassembled first, then the high power incandescent bulb is put into the reducer motor to bake, or the speed motor is put into the drying room for drying. This method is easy to operate, safe and reliable, but only suitable for easy disassembly of small deceleration motor. But for large, medium-sized or difficult to disassemble the slowdown of the motor, relatively large workload, but also reduce the feasibility. It should be noted that when the method is operated, the bulb or heat source can not be too close to the coil, so as to prevent burning out of the coil, and to carry out heat preservation on the outer shell of the speed reducing motor by covering objects such as canvas.
Three, drying in the excitation coil
The excitation coil drying method is to turn the excitation coil on the stator coil core of the decelerating motor and connect the alternating current to make the stator produce magnetic flux, and the stator of the motor is dried by its iron loss