Frequency Converter: Safety Expands

Thanks to the new premium frequency inverter, Bonfiglioli guarantees greater functional safety in a digital form for operators and machinery. All this together with a simplification of configurations, and eliminating unnecessary downtime

The AxiaVert premium frequency inverter launched by Bonfiglioli offers a wide range of integrated functional safety functions: compliant with international EN ISO 13849-1 and IEC 61508 standards, they are combined in different versions so as to make it possible to choose the most suitable option in terms of cost and performance. The functions are suitable for both open and closed loop applications and allow control not only via safe digital I/O but also via the Functional Safety over Ethercat (FsoE) safety fieldbus, extending the level of flexibility and digital integration possibilities of the system.

Safe Brake Control and Safe Torque Off  function for industrial lifting.
Safe Brake Control and Safe Torque Off function for industrial lifting.

A function to set speed thresholds dynamically

One of the main innovations introduced with AxiaVert is the Safe Limited Speed (SLS) safety function, both sensorless and closed loop, available in the version with Sliding Limits: it gives the possibility to set different safety speed thresholds dynamically directly via the FsoE fieldbus.
This function is very interesting for machines which process materials with high performance spindles, where it is often necessary to set different safety speed limits dynamically according to the tool in use, avoiding unnecessary downtimes.
This guarantees a high level of flexibility in setting the working cycles, and avoids the use of encoders thanks to sensorless safety technologies. This ensures the protection of the machine itself and especially of the operator, and no additional protective devices are required.

Overview of functional safety functions integrated in AxiaVert.
Overview of functional safety functions integrated in AxiaVert.

Safe handling in the lifting sector

Thanks to well-established partnerships with companies specialising in the construction of industrial lifting machinery, Bonfiglioli can claim in-depth competence and with its offer meets the typical requirements of the sector, which requires high performance combined with high safety. The integrated Safe Brake Control (SBC) feature ensures safe handling of suspended loads. This function transmits a safe output signal to control an external mechanical brake and is activated in conjunction with the Safe Torque Off (STO) function to remove power and prevent uncontrolled motor restarts.

Speed and movement limits for palletisers with robotic arm.
Speed and movement limits for palletisers with robotic arm.

Limiting speed and movement for safe human-robot interaction

The safety features included in the AxiaVert Motion variant meet the needs of applications with complex movements, enabling operator safety and eliminating downtimes. A useful application example to illustrate the main functions is the robotic arm palletiser. The safe interaction of the moving machine with the operator is given first of all by the SLS functionality in closed loop version: if the operator approaches the moving arm entering an area considered at risk, the machine reduces its speed without interrupting its activity. In the case of a palletiser with robotic arm operating on two sides, the Safe Direction (SDI) and Safe Limited Position (SLP) functions ensure that the production cycle is maintained at maximum efficiency for completely safe human-machine interaction. Let us see them in detail. The SDI functionality controls that the motor does not move in a direction other than the one defined as safe. Therefore, if a safety sensor signals that the operator has entered an area considered to be at risk, the SDI function is activated and the robot will move according to a trajectory set to avoid contact. If the operator enters an area considered unsafe, Safe Stop 1 (SS1) mode ensures a controlled stop of the robot. With the SLP functionality, on the other hand, it is possible to set a position limit to the movement of each axis, preventing it from being exceeded. The operator can thus safely approach the palletiser to pick up a complete pallet while the robot continues to work to fill the pallet on the opposite side, without having to stop.