Safety in fail-safe mode
The preconfigured fail-safe circuit in the ready-to-install control cabinet is a safe and low-cost alternative when it comes to fail-safe technology. It replaces a single-acting actuator and guarantees that the actuator assumes a predefined safety position in the event of a pressure and/or power failure.
The fail-safe circuit comes in three different versions, “Fail-Safe Standard“, “Fail-Safe Plus – Always Safe” and “Fail-Safe Plus – Manual Override” to suit different customer requirements. In all three fail-safe versions, the actuator assumes its predefined safety position if the compressed air and/or power supply fails. This is achieved by using compressed air from the reservoir to move the actuator.
This fail-safe circuit, configured by Festo in a ready-to-install control cabinet, is a low-cost and effective safety solution compared with a single-acting linear cylinder. The pre-assembled solutions simplify the engineering process. They are ideal for use in applications such as rainwater overflow tanks in water technology.
Fail-safe times three
If the power and/or compressed air fails, the actuator assumes its predefined safety position. This is the basic functionality provided by the “Fail-Safe Standard” version. With the “Fail-Safe Plus – Always Safe” version, the actuator moves into the predefined safety position unless the circuit is in manual operation. It is possible to switch between manual and automatic operation, but only when compressed air is available.
With the “Fail-Safe Plus – Manual Override” version, the “dominant” manual operation applies. If there is a compressed air and/or power failure, the actuator moves into the predefined safety position unless the circuit is in manual operation. It is possible to switch between manual and automatic operation. In manual operation, the actuator can be moved when there is no compressed air and power until the air reservoir is completely empty. The air reservoir must always be customised in accordance with the customer’s requirements.
Festo is a global player and an independent family-owned company with headquarters in Esslingen am Neckar, Germany. Festo has set standards in industrial automation technology and technical education ever since its establishment, thereby making a contribution to sustainable development of the environment, the economy and society. The company supplies pneumatic and electrical automation technology to 300,000 customers of factory and process automation in over 35 industries. The LifeTech sector with medical technology and laboratory automation is becoming increasingly important. The products and services are available in 176 countries. With about 20,000 employees in over 250 branch offices in 61 countries worldwide, Festo achieved a turnover of around €2.84 billion in 2020. Each year around 8 % of this turnover is invested in research and development. In this learning company, 1.5 % of turnover is invested in basic and further training. Festo Didactic SE is a leading provider of technical education and training and offers its customers worldwide comprehensive digital and physical learning solutions in the industrial environment.