In the field of industrial automation, variable frequency drives are not only the power source of motors, but also the core execution and feedback node of the entire control system. The ACTION 401/201 series frequency converter launched by Bonfiglioli provides a flexible and high-performance drive platform for system integrators and field engineers with its wide power coverage from 0.55 kW to 65 kW, modular hardware architecture, and rich built-in PLC and bus communication functions. This article will systematically explain the deployment points and technical details of this series of drivers in practical engineering from the dimensions of hardware selection, mechanical installation, electrical integration, software configuration, and common problem handling.
Key points for product positioning and selection
The ACTION series is divided into two sub series: ACT201 (230V level, single-phase/three-phase input) and ACT401 (400V level, three-phase input), which correspond to different application scenarios of power grid systems.
1. Power range and model selection
ACT201 covers 0.55 kW to 3.0 kW and is suitable for low-power applications such as small mechanical equipment, conveyors, pumps, etc. Supports 200-240V ± 10% single-phase or three-phase input, compatible with TN and IT power grids.
ACT401 covers from 0.55 kW to 65 kW (with a total of 6 chassis sizes ranging from 1 to 6) and is suitable for 360-480V ± 10% three-phase industrial power grids. The new Size 6 expands the high-power range of 37-65 kW, filling the gap of the previous generation product.
2. Selection and matching principles
This series is selected one-to-one according to the motor power, for example, a 7.5 kW motor directly corresponds to the ACT401-21 model (Size 3). This simplified model reduces the risk of selection errors.
Capacity needs to be confirmed based on application overload requirements: The standard provides the ability to withstand 150% overload for 60 seconds and 200% overload for 1 second, suitable for heavy-duty startup or impact load scenarios.
Mechanical installation and heat dissipation engineering
Correct installation is the foundation for ensuring the long-term reliable operation of the frequency converter. The ACTION series offers a variety of mechanical installation kits to adapt to different cabinet environments.
1. Standard installation and optional kits
The standard configuration includes MSTD installation kit (backplane fixation).
Optional MPSV through installation (suitable for high protection levels or enhanced heat dissipation, by threading the heat sink out of the cabinet to achieve heat dissipation).
Optional MNVIB anti vibration installation (used for installation on equipment that generates strong mechanical vibrations, such as presses and crushers).
Optional MDIN DIN rail installation (limited to Size 1 and Size 2, maximum 4 kW, for fast modular assembly).
2. Rating reduction and environmental adaptability
Temperature derating: When the ambient temperature exceeds 40 ℃, a derating of 2.5%/K is required, with a maximum allowable temperature of 55 ℃.
Altitude derating: When the installation altitude exceeds 1000 meters, the derating will be reduced by 5%/1000 meters, with a maximum of 4000 meters.
Cold Plate Option: For high protection level requirements (such as cabinets with IP54 or higher), the Cold Plate cooling version can be selected to export heat through the cabinet backplane, avoiding dust inhalation caused by internal fan cooling.
Switching frequency: All models do not require derating at a switching frequency of 8 kHz, which reduces motor noise while maintaining rated output capacity. This is an important engineering advantage of this series.
Electrical Connection and Power Terminal Design
1. Power supply and motor wiring
Plug in power terminals: 4 kW and below models use plug-in power terminals for quick replacement and maintenance, without the need to re crimp cables.
DC bus connection: All models provide DC link terminals, supporting multiple frequency converters to share DC bus power supply, achieving energy sharing and regenerative braking energy feedback, suitable for frequent start stop or lifting applications.
Built in braking transistor: The standard configuration includes a braking unit, which only requires an external braking resistor to achieve energy-efficient braking, reducing system costs and cabinet space.
2. Control terminal and signal isolation
Standard configuration includes 6 digital inputs, 1 multifunctional input (configurable as analog/pulse/digital), 1 digital output, 1 multifunctional output, and 1 relay output.
The control terminal also adopts a plug-in design, which facilitates the disconnection of the control circuit during debugging and maintenance without affecting the power wiring.
Multi functional input supports multiple signal types such as ± 10V, 0-20mA, 4-20mA, etc., and can flexibly connect various sensors and upper computer commands.
Expansion module selection and system integration
The maximum engineering flexibility of the ACTION series comes from its three slot modular architecture (slot A/B/C), which supports plug and play for I/O expansion, speed sensor interfaces, and fieldbus communication modules.
1. Selection of Communication Module (CM)
CM-232 (RS232): Used for point-to-point PC debugging and parameter monitoring, supporting VPlus software (excluding oscilloscope function).
CM-485 (RS485): Supports multi station networks with up to 30 nodes, suitable for protocols such as Modbus RTU, with a maximum communication distance of 1200 m (at 9.6 kbps).
CM-PDP (Profibus DP): Supports PPO1~PPO4 types, configured through GSD files, suitable for high-speed data exchange with PLCs such as Siemens.
CM-CAN (CANopen): Compliant with DS-301 V4.02, supporting up to 127 nodes, suitable for distributed automation systems.
2. Speed sensor and I/O expansion module (EM)
EM-ENC-01~05: Supports incremental encoders (5V/24V line drive, including Z-pulse), providing encoder signal frequency division output (pulse repetition), facilitating master-slave synchronization or electronic gear.
EM-RES-01/02: Supports rotary transformer interface for high dynamic and high-precision servo control, providing absolute position information even at zero speed.
EM-I/O-01~04: Provides additional digital/analog I/O and PTC/KTY temperature probe inputs to meet different application requirements.
EM-SYS: System bus module (based on CANopen), supporting up to 64 frequency converters for high-speed data exchange through PDO and SDO, achieving complex master-slave synchronization and distributed control.
3. Module installation restrictions
When installing CM-CAN in slot C, EM-SYS cannot be installed in slot B at the same time (both share system bus resources).
KP232 and CM-232 are both RS232 interfaces but installed in different locations. KP232 supports VPlus oscilloscope function (115 kbps), while CM-232 only supports up to 19.2 kbps and does not include oscilloscope function.

Software Configuration and Core Function Application
The ACTION series has rich built-in software functions that can be configured through the KP500 control unit (with parameter copying function) or VPlus Windows software.
1. Control mode selection (parameter P030)
Configuration 110 (simple sensorless control): default mode, suitable for parallel motor drive or low dynamic requirements.
Configuration 111 (sensorless control with PI regulation): Suitable for turbomachinery such as pumps and fans that require constant pressure/constant current control.
Configuration 210/215/216 (magnetic field orientation control with speed sensor): requires an external encoder to achieve zero speed full torque, high-precision speed and torque control, suitable for elevators, winding, and synchronous transmission.
Configuration 410/430/460 (Extended Tuned Sensorless Control): Through motor parameter identification and self-tuning, high dynamic performance is achieved without sensors, suitable for applications without encoders but requiring fast response.
2. Brake control and motor chopper
Brake control: For suspended loads such as elevators and cranes, provide logical output to control mechanical brake, and compensate for mechanical action delay through timers (P790~P795) to prevent rolling.
Motor chopper (P507): Using the motor itself as a braking resistor, the braking energy is consumed in the motor winding, especially suitable for high inertia flywheel loads, which can save the cost and space of external braking resistors.
3. Positioning and timer function
Positioning from reference point (P458~P464): By defining the reference point through external sensors (such as proximity switches), relative positioning can be achieved without the need for an absolute value encoder.
Timer logic: Equipped with 2 programmable timers with a delay range of 10ms to 650 hours, it can achieve complex timing control (such as sequential start, delayed stop, and fault delay confirmation), reducing the I/O occupation of external PLCs.
Electromagnetic Compatibility (EMC) and Harmonic Suppression Engineering
The electromagnetic environment in industrial sites is complex, and the ACTION series provides both internal and external filtering solutions.
1. Scope of application of built-in filter
All ACT201 series and ACT401 9.2 kW and below models are equipped with EMI filters that comply with EN 61800-3 standards.
The built-in filter can meet the Class A Group 2 radiation limit under standard configuration (motor cable ≤ 10m).
2. Combination strategy of external filter and reactor
For models with a power output greater than 7.5 kW, an external EMI filter (such as FTV007B/018B/040B) is required.
Line Choke: It is recommended to use it in the following situations:
When the ratio of short-circuit power to inverter power is less than 1%.
When the capacity of the power transformer is ≤ 500 kVA.
ACT201 must be used during single-phase/two-phase operation.
It is recommended to choose 4% for the voltage drop of the reactor, which can effectively reduce harmonic currents and extend the life of the DC bus capacitor.
Installation sequence: It must be connected in the order of mains power → incoming reactor → EMI filter → frequency converter, otherwise the filtering effect will be greatly reduced.
Dv/dt filter and sine wave filter: used for long motor cables (>50m) or in situations where motor insulation requirements are stringent, they can suppress overvoltage spikes and protect motor windings.
Auxiliary tools: VPlus oscilloscope and diagnostics
VPlus oscilloscope function: It needs to be used in conjunction with KP232 interface (115 kbps, not supported by CM-232). It can display 4 waveform curves (current, voltage, speed, torque, internal status bit, etc.) simultaneously, with a sampling interval of 2ms~32ms, a sampling depth of 1MB, and a maximum storage record of 60 minutes.
Parameter copying: The KP500 control unit has built-in non-volatile memory, which can copy the complete set of parameters of a frequency converter to other devices of the same model, greatly accelerating the progress of batch debugging.
Reference for troubleshooting typical engineering faults
Phenomenon 1: No display when the frequency converter is powered on
Check if the input power supply voltage is within the allowable range (ACT401: 320~528V AC).
Check if the DC bus terminal is short circuited or if the external braking resistor is grounded.
Check if the built-in EMI filter triggers protection due to ground fault.
Phenomenon 2: Overcurrent (OC) reported during motor start-up
Check the insulation and phase to phase resistance of the motor cable (eliminate short circuits).
Confirm whether the motor parameters match the actual conditions (rated current, power factor).
Attempt to extend the acceleration ramp time (P120) or reduce the initial acceleration torque.
For overloaded applications, confirm that the correct control mode has been selected (such as FOC configuration with sensor 210).
Phenomenon 3: Profibus communication failure
Check if the GSD file version matches the PPO type setting.
Confirm if the terminal resistor dip switch of the CM-PDP module is located at the physical end of the bus.
Check if the node address configured by the main station is consistent with the frequency converter parameter P707.
Phenomenon 4: Overheating of braking resistor or poor braking effect
Check if the brake transistor is conducting normally (parameter P500).
Confirm whether the resistance value of the braking resistor meets the recommended value in the manual to avoid overcurrent caused by too small a resistance value.
Check if the DC bus voltage has reached the brake activation threshold (approximately 390V DC for 230V system, 780V DC for 400V system).
