DC Motor Selection

The basic contents required for motor selection are: drive load type, rated power, rated voltage, rated speed and other conditions. Load Type DC Motor, Asynchronous Motor, Synchronous Motor.

Here is the list

• How to choose the right DC motor

• How to judge the fault of DC motor

How to choose the right DC motor

For production machinery with stable load and no special requirements for starting and braking, ordinary squirrel-cage asynchronous motors should be preferred, which are widely used in machinery, water pumps, fans, etc. Large starting and braking torques are required, such as bridge cranes, mine hoists, air compressors, irreversible rolling mills, etc., and wound asynchronous motors should be used.

In the occasions where there is no speed regulation requirement, constant rotational speed or improved power factor, synchronous motors should be selected, such as medium and large capacity water pumps, air compressors, hoists, mills, etc. For production machinery that requires a speed regulation range of more than 1:3 and requires continuous, stable and stable speed regulation, it is advisable to use separately excited DC motors or squirrel cage asynchronous motors or synchronous motors with variable frequency speed regulation, such as large precision machine tools, gantry motors Planers, rolling mills, hoists, etc. For production machinery that requires large starting torque and soft mechanical characteristics, series or compound excitation DC motors are used, such as trams, electric locomotives, heavy cranes, etc.

How to judge the fault of DC motor

When the motor runs or fails, four methods of watching, listening, smelling and touching can be used to prevent and eliminate the fault in time to ensure the safe operation of the motor. Observe whether there is any abnormality during the operation of the motor, which is mainly manifested in the following situations.

1. When the stator winding is short-circuited, you may see smoke from the motor.

   
   

2. When the motor is seriously overloaded or run with phase loss, the speed will slow down and there will be a heavy "humming" sound.

   
   

3. The motor maintenance network operates normally, but when the machine stops suddenly, sparks will appear at the loose connection; the fuse is blown or the parts are stuck.

   
   

4. If the motor vibrates violently, it may be that the transmission device is stuck or the motor is not fixed firmly, the anchor bolts are loose, etc.

   
   

5. If there are discoloration, burn marks and smoke marks on the contact points and connections of the motor, it indicates that there may be local overheating, poor contact at the conductor connection or burnt out windings.

The motor should emit a uniform and brisk "humming" sound during normal operation, with no murmurs and special sounds. If the noise is too large, including electromagnetic noise, bearing noise, ventilation noise, mechanical friction noise, etc., it may be a harbinger of failure or failure phenomenon.

Hangzhou New Hengli Electric Machine MFG. Co., Ltd.  has various DC motors that can provide the increasing of products, and make them more effective, reliable, and consistent.