When a gear motor in a humid environment that has been not used for a period of time is activated again, the insulation resistance of the gear motor winding will be reduced, and could even be as low as zero. In this case, drying should be carried out to ensure the insulation resistance and absorption ratio reach the specified values. If a damp gear motor is put into operation directly, it’s possible that it could lead to the insulation breakdown of the coils of a gear motor and result in an accident. Let’s learn how to dry gear motors affected by damp environments.
Electric Welder Drying Method
Before use, connect the connection heads of the winding of gear motor affected by a damp environment in series and ground the casing, so that the three groups of winding can be heated and dried. An ammeter can be connected to observe whether the current of gear motor reached the rated value. Using an AC welding machine to dry the gear motor does not require disassembly of the gear motor, which reduces the workload. At the same time, with electricity, the gear motor heats up with its own resistance, so that the coils can be evenly heated and the drying effects are better. This method, however, is applicable to some gear motors and cannot be used for a long time. This is because the welding machine could get burned out due to the excessive current applied to the welding machine transformer.
The operating wiring of the DC welding machine is similar to that of the AC welding machine, and a DC ammeter should be connected. It's convenient to dry the gear motor affected with damp using a DC welding machine, which can dry large and medium-sized gear motors and high-voltage gear motors for a long time and the internal components of DC welding machine will not be damaged due to long-term or operation under a high-current. It's worth noting that all contact points should be in good contact and tight when using the above two methods for drying. Special wires should be used for the outgoing wires of the welding machine, and the required section size should meet the current carrying capacity of the welding machine output current.
Heating Method of External Heat Source
For damped gear motors, first disassemble and inspect it, then place a high-power incandescent bulb inside the gear motor for baking, or place the gear motor in a baking room for drying. This method is easy, safe and reliable, but it is only suitable for miniature gear motors that are easy to dismantle and inspect. Special attention should be paid to the fact that the bulbs or heat source should not be too close to the coils to prevent the coils from burning out. Canvas and other articles can be covered by the shell of the gear motor for heat preservation.