Safety Relay - A strong supporter when designing a safety circuit!Follow article
Panasonic safety relay (SF-M relay)
Safety Relay Essential for Constructing Safety Circuits
Machine tools, robots, safety relay units, programmable logic controllers, and other similar devices are collectively called industrial equipment.
Safety standards are an important factor when designing the electrical circuits making up these types of equipment. Since the international standard ISO13849-1 was revised in 2006, a trend of defining the safety of various devices and equipment in terms of functionality and reliability has been growing widespread to the point where it has become the core guidelines for safety standards. This trend has changed the approach to constructing safety circuits in industrial equipment, leading to new and more varied options for determining component types and design methods.
ISO13849-1 includes three safety indexes: (1) category, (2) performance level (PL), (3) safety integrity level. For each safety index, safety requirement ranks are set which increase in number depending on the products and applications to which the standards apply. Fig. 1 shows an example of components that meet safety requirements ranked for each safety index. Among these main components, the safety relay is the most critical piece for meeting safety requirements on each of the three safety indexes.
The safety relay is ideal for constructing a safety circuit as it provides a forcibly guided contact mechanism. When selecting a proper safety relay, one must make the decision based on the (1) use, (2) contact structure, (3) operational function, (4) coil voltage of the relay, and (5) method of mounting the relay. Examining service conditions in detail is the key to selecting an optimum relay. The following link provides information that is helpful for selecting such a relay.
Panasonic Safety Relays
Panasonic offers a lineup of safety relays (click here to see more) shown in Fig. 2. The company's product lineup includes relays with various contact structures, flat-type relays with a low profile, and slim-type relays allowing a reduced mounting area. This group of products will help you make better decisions in selecting what is needed.
Panasonic launched a new product, the SF-M series relay, in October 2020. This is a safety relay with a 1a-1b contact structure that is required by today's safety circuits for industrial equipment, robots, and safety modules. The SF-M has a low profile and small size that is still capable of switching multiple circuits. With its forcibly guided contact structure, the SF-M relay conforms to IEC61810-3 international safety standards. The low profile and small size allows the relay to be mounted within a limited space and is, therefore, more suitable to be combined with multiple components in practical applications while still meeting size reduction and space-saving in equipment and circuit design. With these features, this relay is perfect for small size safety circuit design.
"Pearls of Wisdom" on Automation Controls - This page provides lots of relevant information useful for engineers, covering knowledge ranging from basic to practical applications of control equipment.