When to Use Multi-Function Safety Relays

Overview:

Often the Best Choice for Applications Where SingleFunction Relays Aren’t Capable Enough and a Safety-Rated PLC is Overkill

Multi-function safety relays are often the best choice for applications where single-function relays aren’t capable enough and a safety-rated PLC is overkill. This white paper explains how to determine when applications will benefit from multi-function safety relays over other options. Many machines and robots require safety circuits to stop all or part of operation in the event of an emergency. Safety circuits are also used to keep all or part of a machine or robot from running while there is human activity in close proximity, either for normal operations or maintenance.

One or more multi-function safety relays can often be used to replace many basic single-function safety relays, simplifying installations and saving money. In many cases, multi-function safety relays can be used instead of a safety-rated PLC, resulting in substantial savings while streamlining implementation and maintenance. machines and robots with just a couple of basic safety inputs, such as an E-stop and one or two door switches or other safety-related inputs, are typically best served by a safety system with one or two single-function safety relays. When a machine has many I/O points, with a high proportion safety-related, a safety-rated PLC is often the best fit. But for a machine or robot in between these two extremes, an easy to configure and inexpensive safety system using multi-function relays may be the preferred choice.

Author:  Lenny Filipkowski, AutomationDirect  | File Type: PDF

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