Posted to News on 9th Oct 2006, 00:00
Safety relay has double reset
The new SRB 100 DR safety monitoring module from Schmersal ensures the safety of machine operators when they are performing repairs or maintenance in hazardous zones with shut-down machine control. Introduced as an extension to the PROTECT-SRB safety relay range, the SRB 100 DR ensures that the machine control can only be switched on after the operator has activated both reset buttons in the correct order and left the hazardous area. The allocated time for the 'double-reset', which normally involves pressing buttons both inside and outside of the hazardous area, can be adjusted by means of a DIP-switch.
When the reset procedure is activated correctly, the SRB 100 DR generates a release signal, which is processed by a standard safety relay module as a start signal. The processing of the button signal is realised through the additional edge detection, ie the trailing edge is monitored after the reset of the command device. In this way, failures such as welded contacts cannot lead to dangerous situations.
