Three drying methods for 6v dc motor factory
During the production process of DC motors, it is often found that some geared motors are left unused for a period of time. When re-enabled, the insulation resistance of the geared windings is reduced. Especially in the rainy season, the air humidity is high, and the insulation value is even reduced to zero. At this time, the drying treatment should be carried out so that the insulation resistance and the absorption ratio reach a predetermined value, and if it is put into operation, the breakdown of the gear of the reduction motor may be broken, resulting in an accident. Here are three simple gear motor drying methods:
1. External heat source heating method
After the dehumidification motor is first disassembled, the high-power incandescent bulb is placed inside the geared motor for baking, or the geared motor is placed in the drying room for drying. This method is easy to operate, safe and reliable, but it is only suitable for small geared motors that are easy to remove. For large and medium-sized gears that are difficult to dismantle, the workload is relatively large, and the feasibility is also reduced. It should be noted that when the method is operated, the bulb or the heat source should not be too close to the coil to prevent the coil from being burned, and the cover of the geared motor casing may be covered with a canvas or the like for heat preservation.
2, electric welding machine drying method
a. AC welding machine drying method Before the operation, the windings of the damp geared motor windings are connected in series, and the casing is grounded, so that the three sets of windings can be heated and dried to monitor the current change during the drying process. An ammeter to see if the current reaches the rated current of the geared motor. Drying the geared motor with AC welding machine does not need to disassemble the geared motor, which reduces the workload. At the same time, in the case of power-on, the geared motor uses its own resistance to heat, so that the coil is evenly heated, and the drying effect is better, but this method is only applicable. The following geared motor can not be used for a long time, because the current applied to the transformer of the welding machine is large when the AC welding machine is working, and it cannot be used for a long time, otherwise the welding machine may be burned out.
b. DC welding machine drying method operation wiring and AC similar, the string current meter should be DC current meter. Drying the damp-reducing motor with a DC welding machine is easy to operate. At the same time, it can dry the large and medium-sized geared motors and high-voltage geared motors for a long time. In this way, when the welding machine is working for a long time or when working with a large current, the internal components are not damaged due to long-time high-current operation, so the large and medium-sized geared motors can be used for a long time. It is worth noting that when drying by these two methods, all the joints must be in good contact and fastened. The electric wire of the welding machine should use special wires, and the cross-sectional size should meet the current carrying capacity of the welding machine output current. Pay attention to the cooling of the welding machine's own transformer, and ensure that the insulation resistance of the geared motor cannot be lower than 0.1MΩ. Also pay close attention to the winding motor temperature and adjust the voltage and current in time.
3. Excitation coil drying method
The excitation coil drying method winds the excitation coil on the stator coil core of the reduction motor, and introduces an alternating current to cause the stator to generate magnetic flux, and relies on the iron loss to dry the stator of the reduction motor.
