A Safe Bet for a Sweet Deal
3 Jan 2022
| Safety at Leuze
Access guarding on pallet magazine – with automatic restart
From risk assessment to validation: our safety solutions provide complete solutions for your systems. Our expert teams’ innovative safety concepts ensure efficient material flow, gapless safety and high availability of your system. Even in applications where classic concepts are pushed to their limits. Always with legal certainty, CE certification and compliance with standards. This makes implementation particularly easy for you.
Pallet magazines are generally loaded using manually operated industrial trucks, such as forklifts. Access guarding at the pallet magazine must ensure material transfer that is safe for the operator.
At the same time, work process interruptions must be reduced to a minimum. This challenge was also taken up by the standardization body of EN 415-4 (Safety of packaging machines - Part 4: Palletizers and depalletizers). The current draft of the standard describes a defined series of signals for initiating an automatic restart for this purpose.
The safety concept of our safety solution based on the revised standard ensures optimum utilization of the pallet magazine and requires no manual operator interventions.
Requirement:
Access guarding of the pallet magazine must prevent the entry of persons and simultaneously permit the entry of pallets by a forklift truck. After the forklift truck has again left the transfer area, restart must occur automatically to minimize the interruption of the work process.
Solution:
The access area is protected by a safety light curtain. In addition, induction loops are embedded in the floor in the areas in front of and behind the safety sensor. These allow the safety system to distinguish between forklift truck and persons.
Operating principle:
When the safety light curtain is triggered, the work process of the pallet magazine is interrupted – regardless of whether a person or a forklift truck interrupted the protective field. If, however, the presence of a forklift truck is detected by the induction loops installed in the floor and if this then correctly executes the specified process sequence, the safety system initiates the automatic restart of the work process.
Advantages for you
- Optimum system utilization through automatic restart of the machine without manual operator interventions
- High reliability and availability
- Low service costs
- Optimum protection against tampering
- Simple integration in the safety circuit of the primary control
System components and safety parameters
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Safety sensors: MLC 500 safety light curtain, with device columns for floor mounting |
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| Induction loop set with evaluation unit | |
| System control: MSI 400 safety control | |
| Leuze safety program | |
| PL d in accordance with ISO 13849-1, SILCL 2 in accordance with IEC 62061 | |
| 2-channel safety output |
