What are the causes of excessive temperature rise during machine operation?

1) The high-voltage motor is overloaded for a long time. When the high-voltage motor is overloaded, the current flowing through each winding exceeds the rated current, which will cause the high-voltage motor to overheat, and if the load is not adjusted in time, the insulation performance of the winding will deteriorate, and eventually cause the winding to be short-circuited or grounded, so that the high-voltage motor can not work normally.

2) Failure to operate in accordance with regulations. High-voltage motors must operate according to regulations, for example, "short-time" and "intermittent" high-voltage motors cannot operate for a long time because their winding wire diameter and rated current are smaller than long-term high-voltage motors.

3) Short circuit in armature windings. It can be checked by a short-circuit reconnaissance, and if the short-circuit point is outside the winding, it can be bandaged and insulated; If the short circuit point is inside the winding, it should be removed and rewound.

4) The main pole winding is open. The winding can be checked with a test lamp, and if the circuit break point is outside the winding, it can be reconnected and insulated; If the break point is inside the winding, it should be removed and rewound.

5) The grid voltage is too low or the line voltage drop is too large (more than 10%). For example, if there is poor contact somewhere in the main circuit of the high-voltage motor or the grid voltage is too low, the electromagnetic torque of the high-voltage motor will be greatly reduced, which will overload the high-voltage motor. Check the main circuit to eliminate poor contact or adjust the grid voltage.

6) The ventilation volume is not enough. If the air volume and speed of the blower are insufficient, the heat inside the high-voltage motor cannot be discharged and overheated, and the appropriate ventilation equipment should be replaced.

7) The rotation direction of the inclined blade fan is improper, and it does not cooperate with the high-voltage motor. At this point, the pitched-blade fan should be adjusted to match the high-voltage motor. Theoretically, high-voltage motors can be reversed, but some high-voltage motors have directional fans, and if they are reversed, the temperature rise will be much exceeded.

8) The armature core insulation is damaged. At this point, the insulation should be replaced.

9) Blocked air ducts. At this time, the air duct should be cleaned with a brush.

The load is too heavy, the iron loss, that is, the eddy current is too large, which will make the motor seriously heated. Copper loss, that is, resistance loss, is generally not too serious and does not cause serious heating. For excessive load can reduce the load, excessive eddy current should be selected in the motor manufacturing process to choose high resistivity, high permeability of ferromagnetic materials as the core.

Overload operation, current exceedance. It is necessary to lighten the load and repair the mechanical failure of the load. The environment is harsh.

Ventilation needs to be improved, exposure to the sun, temperatures should be reduced, and frequent start-ups should be reduced. The voltage is unstable, too high or too low, resulting in excessive current. The power supply problem needs to be solved.

3 phases are asymmetrical, or absent. The power supply problem needs to be solved. Motor failure, winding open, short circuit, leakage, poor contact, bearing wear.

Repairs are needed. <>

During the operation of the pressur, when the heat generation and heat dissipation reach a balanced state, the temperature of each part tends to be stable. If the oil temperature is higher than usual by more than l °C under the same conditions, or the load remains the same, but the temperature continues to rise, it can be considered that a fault has occurred inside the transformer. The load is large and the current is large, resulting in serious heating, and the specifications of relays, protectors, and switch wires are too small.

The load is not working properly, and the lack of power supply is the main factor. The temperature rise during the operation of the machine is too high, and from the perspective of the equipment itself, there are generally abnormal working conditions of friction parts such as bearings; Poor lubrication or cooling of the system; or too much oil in the tank or deterioration of oil quality. From the perspective of process operation, such as the temperature of man-machine materials or gases is too high, and the ventilation and exhaust capacity is insufficient.

The temperature of the machine should be below 20 °, that is, the temperature of the end cover of the motor exceeds the ambient temperature should be less than 20 °, the direct cause of the motor heating is caused by the large current of the judgment wheel in the hole, which may generally be caused by short circuit or open circuit of the coil, demagnetization of the magnet or low efficiency of the motor, etc., and the normal situation is that the motor runs with high current for a long time.