Platform for the food and beverage industry
Pallet warehouses with automatic restart contribute to increased system efficiency with reliable access protection. A new safety solution with induction loops, light barrier and monitored signal sequence meets the requirements of the revised standard EN 415-4, ensuring maximum safety. Induction loops in the safety system distinguish between forklifts and persons.
Manufacturers and operators of machines and systems must comply with legal requirements. Standards also play an important role. They describe requirements and provide support for ensuring safety to machinery and systems. However, they are not legally binding in Europe. For manufacturers or operators of machines or systems, Type C standards are particularly important. These are machine-specific safety standards. These include EN 415-4 "Safety of packaging machines - Part 4: Palletizers and depalletizers and associated equipment. The contents of the 1997 standard have been significantly revised. The upcoming version of the standard sets new requirements for manufacturers and operators. This also affects the access protection of pallet warehouses with automatic restart.
Until now, many material handling stations with automatic restart were protected as follows: electro sensitive protection equipment (ESPE) protected the access point - if the ESPE (walk-in protection / light curtain) is interrupted, the machine and conveyor are stopped. To avoid having to restart the stopped machine after loading an aisle by a supply vehicle, such as a forklift, two induction loops were used as muting signals. These were located in the floor in front of the walk-in guard. When the forklift drove over the induction loops, the walk-in guard was temporarily overridden. This solution no longer corresponds to the current state of safety technology: the system often ends up in a single-channel evaluation logic; as a result, safety under certain circumstances is no longer guaranteed for the given application. A new type of access protection for a pallet warehouse aims to prevent the access of persons, but at the same time allow the access of pallets with a forklift.
Manufacturers and operators can now take advantage of a new solution described in the future version of standard EN 415-4. It corresponds to the current state of the art. Two induction loops are also used for this type of access protection on pallet warehouses. The difference with traditional concepts is that the two induction loops are not located in front of the danger zone. Instead, one loop is located outside the hazard zone and the second is located behind the walk-in guard, inside the hazard zone. The ESPE - the optoelectronic protection device - remains in place. As before, it separates the traffic and danger zones. There is also a safety system that monitors a defined sequence of signals and initiates the automatic restart.
Leuze offers the described safety solution for pallet warehouse access protection with automatic restart as a complete package that has been tested and validated for safety with the necessary components.
