Technical Specifications

FAQ

1. What is the rated output current of the Allen Bradley 20BH105A0ANNANC0?

The 20BH105A0ANNANC0 has a normal-duty output rating of 105 A and a heavy-duty continuous output rating of 85 A. It can provide 128 A for up to one minute and 170 A for up to three seconds under the specified overload conditions. The drive is rated for 55 kW normal-duty operation and 45 kW heavy-duty operation.

When selecting this drive for a motor, the motor’s nameplate current should be compared directly with the drive’s current rating. Motor power alone should not be used as the only selection criterion, particularly for applications involving high starting torque, frequent acceleration, or significant load fluctuations.

2. What input power supply does the 20BH105A0ANNANC0 require?

The 20BH105A0ANNANC0 is designed for a 540 VDC input supply and uses a three-phase power architecture. It is a DC-input version of the PowerFlex 700 drive family and does not use the conventional three-phase AC input arrangement found on many standard AC-input drives.

Before installation, the DC bus voltage should be verified carefully and the external power system should be checked for correct voltage, polarity, protection, and grounding. Incorrect DC input conditions can cause immediate drive faults or damage to the input and power conversion circuitry.

3. What motor control methods are supported by the 20BH105A0ANNANC0?

The drive supports vector-based motor control as well as V/Hz control. Sensorless vector control can provide improved speed and torque performance without requiring a standard encoder feedback system, making it suitable for many industrial applications.

For vector control, accurate motor nameplate information is important. Parameters such as motor voltage, rated current, frequency, speed, and power should be entered correctly. Incorrect motor data can result in excessive current, unstable speed, poor torque response, or difficulty completing the motor identification process.

4. Does the 20BH105A0ANNANC0 have an internal brake resistor?

No. This configuration does not include a drive-mounted brake resistor and is specified without a brake IGBT. If the driven machine has high inertia or requires frequent rapid deceleration, the braking requirements should therefore be evaluated separately during system design.

During deceleration, a motor can return regenerative energy to the DC bus. If this energy causes the DC bus voltage to rise beyond the allowable limit, the drive may generate an overvoltage fault. Applications such as high-inertia conveyors, centrifuges, hoists, and other rapidly decelerating machinery may require an appropriate external braking or regenerative energy solution.

5. Does the 20BH105A0ANNANC0 support encoder feedback?

The standard configuration is supplied without feedback. Sensorless vector control can therefore be used without an external encoder for many general-purpose motor applications.

For applications requiring precise low-speed torque, highly accurate speed regulation, synchronization, or closed-loop operation, an appropriate feedback option may be required. When replacing an existing PowerFlex drive, it is important to check whether the original system uses encoder feedback before selecting the replacement configuration.

6. Can the 20BH105A0ANNANC0 be integrated with a PLC or DCS?

Yes. The drive can be integrated into an industrial control system using its available control I/O and compatible communication options. The standard configuration provides six digital inputs, three digital outputs, two analog inputs, and two analog outputs, allowing common commands and feedback signals to be exchanged with a PLC, DCS, or other control equipment.

Typical hardwired control applications can use digital inputs for start/stop and direction commands and analog inputs for speed references. Digital and analog outputs can be used to provide drive status, operating conditions, or process feedback. For network-based control, the appropriate communication interface and protocol should be selected according to the automation architecture.

7. What should be checked when the 20BH105A0ANNANC0 trips on overcurrent?

The first step is to determine when the overcurrent occurs. If the fault appears immediately during startup, check the motor data, motor wiring, mechanical condition, and starting parameters. If the fault occurs during acceleration, the acceleration time may be too short for the connected load, particularly when the machine has high inertia.

For overcurrent during normal operation, inspect the driven equipment for mechanical binding, excessive load, bearing problems, or sudden process changes. The motor cable and output terminals should also be checked for short circuits, insulation problems, loose connections, or phase abnormalities.

The drive’s instantaneous current limit is approximately 220–300% of rated current, depending on the drive rating. Repeated trips after the external motor and load have been verified may indicate a problem involving the power section, output circuit, or control system and should be investigated systematically rather than repeatedly resetting the drive.

8. How should acceleration and deceleration times be configured on the 20BH105A0ANNANC0?

The acceleration and deceleration times can be configured over a broad range up to 3600 seconds. The correct setting depends on motor inertia, load characteristics, required production cycle, and the amount of regenerative energy generated during deceleration.

If acceleration is set too aggressively, the motor may demand excessive current and trigger an overcurrent condition. If deceleration is too short, regenerative energy can raise the DC bus voltage and potentially cause an overvoltage trip.

For commissioning, it is generally better to begin with conservative acceleration and deceleration settings. The machine can then be tested under actual load conditions while monitoring motor current, speed response, and DC bus behavior. The times can subsequently be optimized to achieve the required cycle time without creating unnecessary electrical or mechanical stress.