Motor common sense

Hebei Mengniu Group-Hengshui Motor Co., Ltd.-Welcome!

The correct installation, use and maintenance of the motor can avoid accidental failure and prolong service life.

First, check

1. Carefully check the nameplate data to confirm that the motor model meets the requirements for use.

2. Measure the insulation resistance of the motor winding to the outer casing with a 500V megger. The insulation resistance should be greater than 0.5MΩ.

Second, the installation

1. The motor is generally installed in a clean and dry place indoors. The surrounding air must be well ventilated. The maximum ambient air temperature does not exceed 40 °C, the lowest temperature is not lower than -15 °C, and strong heat radiation should be prevented.

2. The motor control appliance should have phase loss protection and overload thermal protection device. The YA series increased safety motor should select the appropriate overload thermal protection device according to the nameplate tE time and starting current ratio IA/IN.

3. Connect the power cable according to the wiring diagram. The terminal should be fastened. The motor with the cable and wire can be connected directly to the power cable. The joint should be insulated and sealed.

4. When the power line, phase sequence and electric thick lug mark are connected, the motor rotates clockwise from the shaft end. When you need to change the steering, change the position of the two power cords.

5. YD series and other variable-speed multi-speed asynchronous motors use the method of changing the lead-out line to control the change of the speed. In order to ensure the reliability of multi-speed motor operation, it should be noted when designing and operating the control device, when switching to low speed at high speed. The neutral point of the 2Y wiring must be disconnected while the power is off, so as to avoid short-circuiting the power supply when the low-speed winding is turned on. In the process of switching to low speed at high speed, the power supply of the low speed winding must be turned on after the motor is stopped to reduce the impact on the motor and the load. Speed switching should pay attention to the steering of the motor.

6. The motor can be equipped with a coupling, the gear, the belt and the load are mechanically coupled. The 4-pole motor above 4kw and the 4-pole motor above 30kw should not be driven by a belt. The second shaft extension of the double-shaft extension can only be used with a coupling. transmission. The coupling of the coupling, the pulley shaft hole and the motor shaft should be suitable. It is strictly forbidden to strike with a heavy hammer during installation. When using the coupling drive, the center line of the motor shaft and the center line of the load mechanical shaft should coincide.

The coupling retains a 1 to 3 mm clearance in the axial direction. When the belt is used to convey the chamber movement, the center line of the motor shaft should be parallel to the center line of the load mechanical shaft, and the center line of the belt and the center line of the shaft are perpendicular to each other.

Third, grounding

The motor must be reliably grounded. The grounding method and grounding resistance should comply with the electrical safety management regulations such as “Grounding Design Specifications for Industrial and Civil Power Devices” and “Technical Specifications for Factory Power Design”. The grounding resistance is less than 4Ω.

Fourth, start

1. After closing, the motor should start up immediately, reach the normal speed and run smoothly, otherwise the skin will cut off the power immediately, check and eliminate the fault.

2. After starting, pay attention to the motor drive, load machine, voltmeter and ammeter. If there is any abnormality, stop immediately.

3. The continuous start of the no-load of the motor is generally no more than 4 times. After the operation to the hot state, the continuous start must not exceed 2 times, otherwise the motor will be easily burned out.

4. According to the grid capacity, load size and motor power, etc., the starting mode should be reasonably selected. The larger power motor should be started by a triangulation method or a step-down mode.

Five, running

1. The deviation between the power supply voltage and the rated voltage does not exceed ± 5%, and the three-phase voltage imbalance does not exceed 1.5%.

2. The motor running current must not exceed the rated current on the nameplate. The three-phase current unbalance should not exceed 80%, otherwise the motor will be heated or even burned.

3. The surface temperature of the motor casing should be measured by a thermometer not to exceed 80 °C, and the temperature of the bearing should not exceed 95 °C.

4. The motor should be kept clean, dry and well ventilated at all times, and the air inlet and outlet should be kept clear.

5. During operation, the motor appears to emit smoke, severe vibration, abnormal sound, special odor, and the speed is obviously reduced; the load equipment is faulty; when the human body is in shock, it should be powered off immediately.

Sixth, bearing lubrication

l, motor bearing lubrication should be good, after 3000-5000 hours of general operation, should be shut down to maintain or replace the grease, the grease grade is ZL--3 lithium-based grease.

2. If the motor is stored or deactivated for more than two years, the lubrication of the bearing should be checked before use and the grease should be replenished or replaced if necessary.

3. Sealed bearings for motor with center height 132 and below. The center height is above 160. The motor of the frame is generally non-sealed. The seal bearing does not need to be replaced when the motor is in use. Unsealed bearings should be cleaned regularly with clean grease. Grease filling should be appropriate, generally fill the cavity between the inner and outer rings of the bearing 1/3-1/2, the motor with grease injection device, with a lubrication gun to fill 3-4, open the bearing cover before filling The drain hole or cover plate at the bottom, after the motor runs for 20 minutes, then plug the drain hole or the upper cover plate, and the power supply should be shut down when the drain plug or cover is removed.

7. Transportation and storage

During the transportation process, the motor should be free of moisture, the shaft extension is not bumped, and the parts are not damaged. The storage place should be kept clean, dry, ventilated, free of corrosive gases, and avoid sudden changes in ambient temperature.

Eight, quality assurance

1. In the case of correct use and storage by the user in accordance with the provisions of the maintenance and repair instructions, the motor may be damaged or not working due to manufacturing quality problems within one year from the date of purchase or within one year of the company's production date. Our company is responsible for repairing, replacing, and returning.

2, due to user-induced motor failure, our company can provide motor repair service, and charge a certain fee according to the regulations, generally including the following situation: the motor due to the voltage exceeds the rated voltage ± 5% or overload operation, resulting in the burning of the motor; The motor is faulty due to the failure of the three-phase power supply line, causing the one or two phase windings of the stator winding of the motor to burn out; equipment accidents caused by installation, use and maintenance that are not required by the maintenance and repair instructions; motors that are disassembled and repaired by the user.

Nine, maintenance and repair

Pay attention to environmental protection during maintenance and repair of the motor, so that there is no pollution in the maintenance site, and the motor coil must not be removed by fire. For motors that have been used for more than one year, pay attention to checking the oil seals on the outside of the motor end cover, the shaft seal ring, the rubber parts such as the seal ring on the junction box seat and the junction box cover, whether they are cracked, deformed, or worn. Parts that fail to meet sealing performance and requirements should be replaced in time.