Machine & Operator Safety
Modular safety switching devices
November 19, 2007 By Manufacturing AUTOMATION
Modular safety relay combinations from Phoenix ContactÃs PSR safety relay system are designed to take up less space in the control cabinet, minimize wiring costs and extend contacts with maximum safety. The modular system is made up of a universal master, which is responsible for monitoring safety-oriented signals. Subject to requirements, up to four secure off-delay or instantaneous contacts can be connected via the T-bus rail bus connection to extend each module. The power supply, a safe switched potential, and the feedback loop are controlled via the T-bus. Each function can consequently switch to up to ten expansion modules without cross-wiring faults. Pluggable connection terminals are available as standard with screw or spring-cage technology. The new spring-cage connection terminals can be opened at the front with the use of a screwdriver, which opens two clamps. As a result, the wires can be conveniently released and re-wired. Flexible wires with ferrules can be plugged directly into the clamps without the use of tools.