Fenggang Weichuang frequency converter maintenance hotline

Fenggang Weichuang frequency converter maintenance hotline

Dongguan Changping Juyou ElectromechanicalEquipment Maintenance Department specializes in repairing Mitsubishi servo drives, Panasonic servo drives, Yaskawa servo drives, Dongrong servo drives, Sanyo servo drives, Fuji servo drives, Delta servo drives, Omron servo drives, Fanuc servo drives, etc; MitsubishiPLCPanasonicPLCSiemensPLCOmronPLCWait; Various touch screens, frequency converters, industrial circuit boards, etc.

Provide on-site service near the company,Bringing you convenience. We have the advantages of short maintenance cycle, high repair rate, reasonable price, and no need for circuit diagrams, We have also repaired different types of circuit boards for multiple companies. Customers from outside the province can send the servo to be repaired to our company, and we will conduct testing on the day of receiving the goods and arrange for repairs as soon as possible. If the customer's machine is severely damaged and cannot be repaired, our company will not charge any fees. Welcome to consult and cooperate!

Fenggang Weichuang frequency converter maintenance hotline

Common Fault Case Analysis and Maintenance Methods of Weichuang Inverter

1、 Overcurrent fault (OC/OL)

1. ‌Case Analysis‌

• ‌Accelerated overcurrent (OC1)A certain Weichuang AC60 frequency converter frequently triggered OC1 faults after starting, and it was found that the acceleration time was set too short (default 3 seconds), causing a sudden change in current. After adjusting the parameters, it returned to normal79.

• ‌Deceleration overcurrent (OC2)When equipment with high load inertia decelerates, OC2 should be reported. After installing a braking resistor and extending the deceleration time to 15 seconds, the fault will be eliminated710.

• ‌Constant speed overcurrent (OC3)During operation, there was a sudden OC3 malfunction. Upon disassembly and inspection, it was found that the IGBT module had broken down. After replacing the module and repairing the drive circuit, it was restored512.

2. ‌Repair Method‌

• Adjust the acceleration/deceleration time parameters to a reasonable range (recommended ≥ 10 seconds)79；

• Check the insulation resistance of the motor winding (≥ 5M Ω) and eliminate the risk of short circuit56；

• Use an oscilloscope to detect the current detection circuit, calibrate the Hall sensor or repair signal transmission abnormalities512.

2、 Overvoltage/undervoltage fault (OU/LU)

1. ‌Case Analysis‌

• ‌Shutdown overvoltage (OU4)Voltage fluctuations in the power grid lead to DC bus voltage exceeding the limit, and stable operation is achieved after installing an input reactor612.

• ‌Undervoltage operation (LU1)Loose three-phase power supply wiring caused phase loss, and the fault was resolved after re tightening the terminals56.

• ‌Capacitor agingThe undervoltage alarm was caused by the attenuation of the DC bus capacitor capacity, but it returned to normal after replacing the capacitor with the same specification512.

2. ‌Repair Method‌

• Check the input power supply voltage (three-phase imbalance should be ≤ 2%) and the status of the wiring terminals56；

• Replace the filter capacitor (discharge to below 30V before replacement)512；

• Activate the braking unit or adjust the deceleration curve parameters (such as E0-06~E0-08)712.

3、 No display fault

1. ‌Case Analysis‌

• ‌Contactor failureAt the moment of power on, there was no sound of suction or closing, and the display was restored after replacing the contactor1314；

• ‌Voltage regulator resistor open circuitLow voltage power supply failure resulted in black screen, but after replacing the 470k Ω/2W resistor, it returned to normal13.

2. ‌Repair Method‌

• Check if the output voltage of switch power modules (such as KA431, TL494) is normal (± 12V, 5V)1314；

• Check the continuity of the motherboard power supply circuit (with a focus on investigating the power filter capacitor and fuse)1314.

4、 Overheating/Overload Fault (OH/OL)

1. ‌Case Analysis‌

• ‌Cooling fan stops runningDust accumulation on the heat sink caused OH alarm. After cleaning and replacing the DC24V fan, the temperature was reduced by 10 ℃56；

• ‌Load mutationMechanical transmission system jamming triggered OL alarm, resolved after unblocking and adjusting V/F curve57.

2. ‌Repair Method‌

• Clean the dust on the heat sink (recommended monthly maintenance), test the fan speed (normal ≥ 2000rpm)56；

• Optimize torque compensation parameters (such as F0-07) or reduce operating frequency79.

5、 Handling of special fault codes

Maintenance process specification

1. ‌Preliminary diagnosisRecord alarm codes and abnormal phenomena (such as odors and abnormal noises)59；

2. ‌Power outage detection‌：

• Use a multimeter to test the forward and reverse resistance of IGBT modules (normal value: CE pole>100k Ω)57；

• Check if the output terminal of the driver circuit optocoupler (such as A3120) is short circuited810；

3. ‌parameter calibrationRestore factory settings and reset motor parameters (power, rated current)67；

4. ‌full loadingAfter 30 minutes of no-load operation without any abnormalities, gradually load to the rated power to verify stability57.

Precautions

• ‌Electrostatic protectionDuring maintenance, it is necessary to wear an anti-static wristband to avoid damaging the motherboard chip57；

• ‌Compatibility of spare partsReplace IGBT with the same prototype number (such as 7MBR25NF-120)712；

• ‌Environmental RequirementsOperating temperature controlled between -10 ℃~40 ℃, humidity ≤ 90%

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