1. Cause of failure ① Power failure (at least two-phase failure); (2) Fuses are blown (at least two phases are blown); ③ The overcurrent relay is too small; ④ The wiring of control equipment is wrong.
2. Troubleshooting ① Check the switch, fuse and junction box of the power supply circuit for breakpoints and repair them; (2) Check the fuse model and fuse reason, and replace it with a new fuse; ③ Adjust relay setting value to cooperate with motor; ④ Correct the wiring.
Second, the motor does not turn after being electrified, and then the fuse is blown.
1. Cause of failure ① Single-phase power supply is insufficient, or the stator coil is connected reversely; ② Short circuit between stator windings; ③ Stator winding grounding; (4) Wrong connection of stator winding; ⑤ The fuse section is too small; ⑥ The power cord is short-circuited or grounded.
2. Troubleshooting ① Check whether one phase of the circuit breaker is not closed, but one phase of the power circuit is disconnected; Eliminate the reverse connection fault; (2) Find out the short circuit point and repair it; ③ Eliminate grounding; (4) Find out the wrong connection and correct it; ⑤ Replace the fuse; ⑥ Eliminate the grounding point.
Third, the motor does not turn and hum after being electrified.
Causes of length failure ① Stator and rotor windings are open (one phase is open) or power supply is out of power; (2) The lead-out wires of the winding are wrongly connected at the beginning and the end, or the winding is internally connected reversely; (3) The contact of power supply circuit is loose, and the contact resistance increases; (4) The motor is overloaded or the rotor is stuck; ⑤ The power supply voltage is too low; ⑥ The small motor is assembled too tightly or there is too much grease in the bearing; ⑦ The bearing is stuck.
2. Troubleshooting ① Find the breakpoint and repair it; ② Check winding polarity; Jud whether that end of win is correct; (3) Tighten the loose wiring screws, judge whether each joint is false with a multimeter and repair it; (4) Load rejection or finding out and eliminating mechanical failure; (5) Check that the specified δ wiring is also wrongly connected to Y; Whether the voltage drop is too large due to the thin power cord and correct it; 6. Reassemble to make it flexible; Replace qualified grease; ⑦ Repair the bearing.
Four, the motor is difficult to start, rated load, the motor speed is lower than the rated speed.
1. Cause of failure ① The power supply voltage is too low; ② Δ connection motor is wrongly connected with Y; ③ Cage rotor is welded or broken; ④ The local coils of stator and rotor are connected by mistake or reverse; ③ Too many turns are added when repairing the motor winding; ⑤ Motor overload.
2. Troubleshooting ① Measure the power supply voltage and try to improve it; ② Correct connection; (3) Check welding and breakpoints and repair them; (4) Find out the mistakes and correct them; ⑤ Restore the correct number of laps; ⑥ Load rejection.
Five, the motor no-load current is unbalanced, and the three-phase difference is large.
1. Cause of failure ① When rewinding, the number of turns of stator three-phase winding is different; (2) The winding ends are wrongly connected; ③ unbalanced power supply voltage; ④ Faults such as turn-to-turn short circuit and coil reverse connection exist in the winding.
2. Troubleshooting ① Rewinding the stator winding; ② Check and correct; (3) measure the power supply voltage, try to eliminate the imbalance; (4) suddenly eliminate the winding fault.
Six, no-load motor, overload, ammeter pointer instability, swing.
1. Cause of failure ① Welding or fracture of cage rotor guide bar; ② Winding rotor fault (one-phase open circuit) or poor contact between brush and collector ring short circuit device.
2. Troubleshooting ① Find out the broken bars and repair or replace the rotor; ② Check the circuit around the rotor and repair it.
Seven, the motor no-load current balance, but the value is large.
1. Cause of failure ① When repairing, the number of turns of stator winding is reduced too much; ② The power supply voltage is too high; ③Y-connected motor is mistakenly connected with δ; (4) When the motor is assembled, the rotor is installed backwards, so that the stator core is dislocated and the effective length is shortened; ⑤ The air gap is too large or uneven; ⑥ When the old winding was dismantled in overhaul, the iron core was burned due to improper hot dismantling method.
2. Troubleshooting ① Rewind the stator winding to restore the correct number of turns; ② Try to restore the rated voltage; Change 3 to y; ④ reassembly; ③ Replace the rotor with a new one or adjust the air gap; ⑤ Repair the iron core or recalculate the winding, and appropriately increase the number of turns.
Eight, the motor running noise is not normal, there is abnormal sound.
1. Cause of failure ① Rotor and stator insulation paper or slot wedge rub; (2) Bearing wear or sand and other foreign bodies in oil; ③ The stator and rotor cores are loose; ④ The bearing is short of oil; ⑤ Air duct stuffing or fan cover wiping, ⑤ stator and rotor iron cores rubbing against each other; ⑦ The power supply voltage is too high or unbalanced; ⑧ The stator winding is wrongly connected or short-circuited.
2. Troubleshooting ① Repair insulation and reduce slot wedge; ② Replace the bearing or clean the bearing; ③ Overhaul the stator and rotor cores; 4 come on; ⑤ Clean the air duct; Reinstall; 6. Eliminate scratches, and if necessary, install the small rotor on the car; ⑦ Check and adjust the power supply voltage; ⑧ Troubleshooting the stator winding.
Nine, the motor vibration is bigger in operation.
1. Cause of failure ① The bearing clearance is too large due to wear; ② uneven air gap; ③ rotor imbalance; (4) the rotating shaft is bent; (5) Deformation or looseness of iron core; ⑥ The center of coupling (pulley) is not corrected; ⑦ The fan is unbalanced; End casing or foundation strength is not enough; Pet-name ruby motor anchor screw loose; Attending open welding circuit of cage rotor; Open circuit of winding rotor; Stator winding fault.
2. Troubleshooting ① Repair the bearing and replace it if necessary; ② Adjust the air gap to make it uniform; ③ Correcting rotor dynamic balance; ④ Straighten the rotating shaft; ⑤ Correct overlapping iron cores, ⑤ Re-correct them to make them conform to regulations; ⑦ Repair the fan, correct the balance and its geometry; 8 reinforcement; Pet-name ruby fastening anchor screw; Attending to repair the rotor winding; Repair the stator winding.
Ten, bearing overheating
1. Cause of failure ① Too much or too little grease; ② The oil quality is not good and contains impurities; ③ Improper cooperation between bearing and journal or end cover (too loose or too tight); (4) eccentric bearing hole, friction with the shaft; ⑤ The motor end cover or bearing cover is installed unevenly; ⑥ The coupling between motor and load is incorrect, or the belt is too tight; ⑦ bearing clearance is too large or too small; ⑧ The motor shaft is bent.
2. Troubleshooting ① Add grease (0/3-2/3 of 65438+ volume) as required; ② Replace clean grease; (3) Too loose can be repaired with glue, too tight should be turned, and the inner hole of the journal or end cover should be polished to make it match; (4) Repair the bearing cover and eliminate friction points; (5) reassembly; ⑥ Recalibrate and adjust the belt tension; ⑦ Replace new bearings; Finally correct the motor shaft or replace the rotor.
Eleven, motor overheating or even smoking.
1. Cause of failure ① The power supply voltage is too high, which greatly increases the core heating; (2) The power supply voltage is too low, the motor runs with rated load, and the current is too large to heat the winding; (3) When repairing and disassembling the winding, improper thermal disassembly method is adopted to burn out the iron core; (4) The stator and rotor iron core rub together; ⑤ Motor is overloaded or frequently started; ⑥ Broken bars of cage rotor; ⑦ The motor lacks phase and operates in two phases; ⑧ After rewinding, the winding is not completely dipped in paint; Pet-name ruby high ambient temperature motor surface dirty, or ventilation is blocked; Attending motor fan failure, poor ventilation; Stator winding fault (phase and turn-to-turn short circuit; Internal connection error of stator winding).
2. Troubleshooting ① Reduce the power supply voltage (such as adjusting the tap of the power transformer). If the wiring of motors Y and δ is incorrect, correct the wiring; (2) increase the power supply voltage or replace the thick power cord; (3) iron core maintenance and troubleshooting; (4) Eliminating rubbing points (adjusting air gap or rotating rotor); ⑤ Load rejection; Control startup according to the specified number of times; ⑥ Check and eliminate rotor winding faults; ⑦ Restore three-phase operation; (8) adopting secondary paint dipping and vacuum paint dipping processes; Pet-name ruby cleaning motor, improve the ambient temperature, take cooling measures; Attending to check and repair the fan, and replace it if necessary; Overhaul the stator winding and eliminate the fault.