Toshiba TOSBERT S7 series frequency converter

OH1 power module overheating 1. Cooling fan failure; 2. Insufficient ventilation gap; 3. The ambient temperature is too high; 4. The fan filter is clogged. 1. Check if the fan is rotating and if there is any abnormal noise; 2. Measure whether the installation gap meets the requirements; 3. Measure the ambient temperature; 4. Check the dust on the fan filter. 1. Replace the fan (model FS-1238); 2. Adjust the installation spacing to the standard value; 3. Install air conditioning or cooling fans; 4. Clean the dust from the filter screen

OV1 DC bus overvoltage: 1. The grid voltage is too high; 2. The deceleration time is too short; 3. Excessive regenerative energy; 4. Open circuit of braking resistor 1. Measure the grid voltage with a multimeter (within ± 10% of the rated voltage); 2. Check the deceleration time parameter (P03.02); 3. Check if the load is an inertial load; 4. Measure the resistance of the braking resistor. 1. Install a grid voltage regulator; 2. Increase P03.02 (such as changing from 2 seconds to 10 seconds); 3. External braking unit; 4. Replace the brake resistor

GF grounding fault 1. Motor grounding short circuit; 2. The output cable of the frequency converter is damaged; 3. Internal grounding of the frequency converter; 4. Excessive grounding resistance. 1. Measure the insulation resistance between the motor winding and the grounding; 2. Check if the outer sheath of the output cable is damaged; 3. Disconnect the motor and measure the insulation output of the frequency converter separately; 4. Measure the grounding resistance. 1. Repair the motor winding; 2. Replace damaged cables; 3. Contact after-sales service for frequency converter maintenance; 4. Rectify the grounding system (grounding resistance ≤ 10 Ω)

Err12 communication fault: 1. Communication cable disconnected; 2. Baud rate mismatch; 3. The address of the slave station is incorrect; 4. Communication interference: 1. Check the RS485 cable connection; 2. Verify the baud rate of the master and slave stations (P20.01); 3. Verify the address of the slave station (P20.02); 4. Check the grounding condition of the shielding layer. 1. Reconnect or replace the communication cable; 2. Unified master-slave station baud rate (such as 9600bps); 3. Correct the slave address (if set to 1); 4. Ensure that the shielding layer is grounded at one end and kept away from the main circuit cables

ALM1 overload alarm: 1. Excessive motor load; 2. The overload protection threshold is too low; 3. Motor stalling: 1. Check the operating current (whether it exceeds the rated current); 2. Check the P06.00 parameter; 3. Check if the motor is stuck. 1. Reduce the load; 2. Increase P06.00 (such as changing from 110% to 120%); 3. Clean up foreign objects from the load and repair the motor

(2) Fault reset method

Common faults (such as ALM1, Err12): After troubleshooting, press the "RESET" button on the panel or long press the "STOP" button for 2 seconds;

Serious faults (such as OC2, OH1): After troubleshooting, disconnect the input side circuit breaker, wait for 5 minutes (capacitor discharge), and then close and energize;

Unable to reset faults (such as EEP1, CPU1): This is an internal hardware fault and requires contact with Toshiba after-sales service for maintenance.

2. Troubleshooting without fault codes but running abnormally

In some scenarios, the frequency converter has no fault codes, but runs abnormally (such as unstable speed and insufficient torque), and needs to be investigated from the following aspects:

Unstable speed: 1 Check whether the analog input signal fluctuates (measure AI1 voltage with a multimeter); 2. Check if the vector control gain (P01.04) is too large; 3. Check if the motor bearings are worn;

Insufficient torque: 1 Check if the torque limit parameter (P04.01) is too low; 2. Confirm whether the control mode is SVC/FVC (with low torque in V/f mode); 3. Check if the grid voltage is too low (affecting output torque);

The frequency cannot reach the set value: 1 Check if the upper limit frequency (P03.05) is lower than the set value; 2. Check if the overload protection is about to trigger (current approaching threshold); 3. Check if the frequency limit function is enabled (P15.09).

Maintenance and lifespan management

1. Maintenance cycle and core maintenance projects

The maintenance of frequency converters is divided into two categories: "regular inspection" and "regular replacement", and the cycle is adjusted according to the operating environment and load rate:

(1) Regular inspection (by cycle)

Maintenance cycle maintenance project maintenance method judgment criteria

Monthly visual inspection of the inverter casing, terminals, and cables for any damage, oxidation, or looseness

Monthly operation data records include operating frequency, current, voltage, module temperature, current ≤ rated current, temperature ≤ 85 ℃

Tighten the main circuit and control circuit terminals with a screwdriver every 6 months without loosening the screws (torque values: M4=2.5N · m, M5=4.0N · m)

Clean the cooling system every 6 months with compressed air (below 0.3MPa) to remove dust from the cooling fan and fins. There is no obvious dust accumulation, and the fan rotates normally