Technical Specifications

FAQ

1. What is the rated output current of the 20BC125A3ANNANC0?

The 20BC125A3ANNANC0 has a rated output current of 125 A. Its normal-duty power rating is 55 kW, while the heavy-duty rating is 45 kW. When selecting this drive for a motor application, the motor nameplate current should be compared with the drive’s rated output current. The load characteristics should also be considered, especially when the machine requires high starting torque, frequent acceleration and deceleration, or continuous operation at a high load level. Correct drive sizing helps maintain stable operation and reduces the possibility of unnecessary overload protection trips.

2. What type of power supply does the 20BC125A3ANNANC0 require?

The drive is designed for a three-phase 380–480 VAC input supply, with 400 VAC as the nominal input voltage and 50 Hz as the specified input frequency. The incoming power should remain within the permitted voltage range and should be connected through appropriately rated protective equipment. During installation, the incoming power cables, circuit protection, disconnecting equipment, and grounding system should be selected according to the actual installation conditions. If the facility has significant voltage fluctuations or electrical disturbances, the power quality should be checked before commissioning to help prevent unexpected drive faults.

3. Does the 20BC125A3ANNANC0 include an internal braking resistor?

The 20BC125A3ANNANC0 does not include an internal braking resistor and is configured without a Brake IGBT. This is an important consideration when the drive is used with high-inertia machinery or applications requiring frequent rapid stopping. During deceleration, the motor can return regenerative energy to the drive’s DC bus, which causes the DC bus voltage to increase. Excessive regenerative energy can result in a DC bus overvoltage condition. If the application requires short stopping times, the mechanical load and braking requirements should be evaluated to determine whether an external braking or regenerative energy management solution is necessary.

4. How should an overcurrent fault be diagnosed on the 20BC125A3ANNANC0?

The first step is to determine when the overcurrent fault occurs. If it happens during startup or acceleration, check whether the acceleration time is too short or whether the machine requires excessive starting torque. If it occurs during normal operation, inspect the motor and mechanical system for excessive friction, binding, blockage, bearing problems, or an unexpected increase in load. The motor cables and terminals should also be checked for loose connections, incorrect phase wiring, or insulation problems. The programmed motor voltage, current, frequency, and speed parameters should be compared with the actual motor nameplate information. Repeated overcurrent faults should be investigated systematically rather than resolved simply by increasing current limits.

5. Can the 20BC125A3ANNANC0 be controlled by a PLC?

Yes. The drive provides 24V I/O for integration with PLC-based control systems. Its digital inputs can be assigned to functions such as start, stop, direction, enable, and fault reset, while the analog inputs can be used for speed references or process signals. Digital and analog outputs can provide drive status, fault information, and other feedback signals to the PLC. The drive can also be integrated into industrial networks when a compatible communication option is installed. During commissioning, each PLC control function should be tested individually to verify the start/stop logic, speed reference, fault reset, status feedback, and response of the drive under normal operating conditions.

6. What is the maximum output frequency of the 20BC125A3ANNANC0?

The maximum output frequency is 420 Hz. However, the maximum frequency of the drive should not automatically be used as the maximum operating frequency of the connected motor. The motor’s rated frequency, maximum permissible speed, bearing limitations, cooling characteristics, and mechanical load must all be considered. Operating a standard industrial motor substantially above its rated frequency can increase mechanical stress and temperature. For this reason, the maximum frequency parameter should be configured according to the motor manufacturer’s specifications and the speed limitations of the driven equipment.

7. What causes a DC bus overvoltage fault on the 20BC125A3ANNANC0?

A DC bus overvoltage fault is commonly caused by regenerative energy returned from the motor during deceleration. High-inertia loads, short deceleration times, and frequent braking cycles can generate significant regenerative energy. Troubleshooting should begin by checking whether the fault occurs primarily during deceleration. If this is the case, review the programmed deceleration time and compare it with the inertia and operating requirements of the machine. Increasing the deceleration time can reduce regenerative energy in many applications. If rapid stopping is required by the process, an appropriate external braking or regenerative energy solution may be required. The incoming AC supply should also be checked for abnormal voltage conditions.

8. What should be checked before commissioning the 20BC125A3ANNANC0?

Before commissioning, verify the three-phase input power, motor wiring, grounding, control wiring, and protective devices. The motor nameplate parameters should be entered accurately into the drive so that the control system can operate according to the actual motor characteristics. Initial testing should be performed at low speed to confirm the correct motor rotation direction and basic drive response. Acceleration and deceleration settings can then be adjusted according to the mechanical characteristics of the machine. For PLC-controlled applications, start, stop, direction, speed reference, fault reset, and status feedback should be tested individually. Proper separation of power and control wiring and correct grounding are also important for reducing electrical interference and maintaining reliable operation.