来源：http://www.jnmcd.com 发布时间：2019-01-11 浏览：次
Most of us are familiar with DC motors, so we should pay attention not only in use, but also before starting. Perhaps many people do not understand it. For this reason, the editor will explain to us the precautions before starting DC motors.
1. Wiring of DC motor
Parallel excitation DC motors are generally adopted in power plants. The armature terminals of H1 and H2 parallel excitation windings are B1 and B2. Its connection mode is that H1 is connected with the positive pole of B1 parallel DC power supply and H2 is connected with the negative pole of B2 parallel DC power supply.
2. Down the Starting Current of DC Motor
In general, except for direct starting of DC motors less than 4KW, the starting current of all DC Motors should be reduced to less than 2 times the rated current of the motor. In order to reduce the starting current, the starting resistance should be connected in series in the armature circuit to limit the starting current or to reduce the starting voltage of the motor to limit the starting current when the motor starts. Because the starting resistance is connected in series in the armature circuit, the use of equipment is simple, economical and reliable, so it is widely used.
3. Coil Problem of DC Contactor
As for the DC contactor used in operation, its contactor coil should be able to operate for a long time. As for CZ0 series contactors, they all run for a short time, so when they are used as long-term contactors, their coils must not be burned. Therefore, after starting, a resistance of about 150 W, 1000 Omega should be added to the running contactors to prevent the coils from burning.
4. Measurement of DC Current
As for the measurement of DC current, shunt type is usually used. A 100A, 75mV shunt is connected in series in the main circuit. The positive and negative poles of the shunt are connected with a 0_100A ammeter of 75mv.
5. Principle wiring diagram of DC motor starting with one-stage series resistance descending starting current.
The above information is our Shandong micro-motor collation and release hope to bring you a little help in the future life of our website is: http://www.jnmcd.com!