Solenoid interlock with innovative operating principle

Individual coding and adjustable latching force

At first sight, Schmersal's new solenoid interlock AZM 300 is significantly different from other switchgear offered on the market. Because of the innovative interlocking system in the form of a Maltese cross, the interlock can be actuated from three sides, which provides for universal application possibilities. One and the same model can be used both on revolving door with left-hand side and right-hand side hinges and on sliding doors.

Another significant advantage of this feature is that the user does not need any additional add-on parts such as a door stop or a latching element, considering that these functions have been integrated in the interlock. This is a most desired practical feature amongst machinery and plant builders.

The AZM 300 integrates another practical function, namely the adjustable latching force, i.e. the non-safety-related interlocking function when the safety guard is unlocked. Because of this feature, the interlocking system can be smoothly adjusted to suit individual requirements.

Not only the mechanical construction of the AZM 300 is innovative; the electronics are also innovative. An integrated RFID sensor detects the identification and the coding of the actuator. This means that the user can choose three different types of coding.

In the basic version, the sensor accepts any suitable target. A second – coded – version only reacts onto an individually assigned target. The teaching procedure can be repeated an arbitrary number of times. Finally, a third variant is available, which only accepts the target that was taught upon the first activation.

In this way, the user can choose the most suitable coding variant for his application. The importance of this function in actual practice cannot be overemphasised: practical investigations and field tests show over and over again that many safety guards are being tampered with. When an individually coded solenoid interlock is used, the tampering cannot be completely excluded, though it can be at least made more difficult.

The new solenoid interlock meets the requirements of Performance Level e or Safety Integrity Level 3. It was designed, amongst other things, on the basis of specific requests formulated by customers from the packaging industry, who were looking for a universally applicable, compact solenoid interlock with coding features and adjustable latching force. Considering that there is a large overlap between the packaging and the food processing industry in the Schmersal clientele, the designers have observed the principles of the hygienic design to the greatest extent during the development of this new switchgear. Dead spaces or areas where material can deposit have been avoided and also the actuator is made up of rounded elements. In addition to that, the AZM 300 is resistant to a great deal of cleaning agents. Because of its protection class IP 69K, it is also suitable for use in hygiene-sensitive areas.

Safety Consulting

The Schmersal Group broadens its service offer with respect to machinery safety. The new Safety Consulting service aims at providing the company´s customers with comprehensive consultancy regarding issues such as the implementation of directives and standards in actual constructional practice.

In recent months, experienced engineers from German plants as well as from multiple European subsidiaries have been qualified as machinery safety experts. They are already on duty in the new Application Center, where they closely collaborate with the local sales engineers and the product management. In other nations, e.g. China and the U.S.A., the consultants will be qualified in September 2010.

The key task of the Safety Consultants will consist in providing the customers with qualified answers to their questions, e.g. which type of safety system must be used, how the safety system must be integrated in the control system and the functionalities of the machine and how the programmable electronic safety system can be configured to optimally meet both the safety requirements and the productivity specifications of the machine.

The assessment of the required Performance Level to EN ISO 13849-1 and the calculation of the actual Performance Level for the selected safety system are two other tasks that the Safety Consultants accomplish for the customers.

The first reactions of the customers onto the new service offer are throughout positive. Uwe Wiemer, Application Center Manager: "Many of our customers want to delegate the configuration of regulation-compliant safety systems to experts, who accept the full responsibility for this assignment. As one of the world market leaders in the safety switchgear business, we have acquired a comprehensive and highly practice-related knowhow in this field. As a result of our collaboration and affiliation to different standardisation bodies, we also have the necessary theoretical ´background´, which is required for configuring standard-compliant safety guards."

Other services will be added to the Safety Consulting, which will be offered worldwide by the Schmersal Group. The objective is to come to a manufacturer- and technology-neutral way of thinking and to develop or to configure complex safety-technical solutions beyond the own product spectrum.

Simultaneously, the usual services rendered by Schmersal will be integrated in the Application Center as well. "We have always undertaken additional tasks such as the parameter setting of safety controllers or making customer-specific modifications to our safety switchgear. That´s our reputation on the market. These tasks are now transferred to our Application Center. As a result of the centralization of our service offer, we can work in a more concentrated manner, thus creating the necessary freedom for development, product management and sales to raise the tone of our ´one-stop shop for safety´ claim on the market."