Stop category 0
	Safety category 4
	3 Safety contacts
	1 Auxiliary contact
	Crossfault monitoring
	Monitored or automatic reset
	Tested for light curtain applications
	Optional with removable terminals

DIN En60204 Section 1 / VDE0113 Section 1 (11/ 98) prescribes that power circuits with a safety function must be specified as per Section 9.4. In such safety circuits auxiliary contac-tors must intervene to guarantee re-dundancy so that, despite the occur-rence of a fault in one of the auxiliary contactors, the safety circuit remains operative.

In every on -off cycle of the machine, the auxiliary contactors must be checked automatically at least once to ensure correct opening and closure of the contacts.

Emergency-stop relay F127 fulfils this requirement – EN954-1 (3.97) – to the highest safety grade 4.

There are models for manual Start (applicable for autostart-function) or for monitored-start-function available. The F127 may be used for single- or dual-channel operation with or without crossfault monitoring.

The dual-channel operation shown in wiring examples 3 and 5 includes crossfault monitoring between both E-stop circuits. That means in case of shorts between the two E-stop channels the F127 will de-energise the outputs. This is achieved by an elec-tronic protection circuit in the safety relay. After elimination of the mal-function, the F127 is ready for oper-ation again.

The versions with monitored start supervise the start circuit and will only

activate the F127 if contacts via terminals S12 and S34 are closing during start conditions.

Models with autostart function will be activated automatically by the supply voltage, if the E-stop circuits and the feedback loop are closed. A start-push-button may be integrated between the feedback-loop (S12-S34) for manual reset.

In autostart-applications where both circuits are not closed simultaneously, (e.g. safety gates) channel 2 has to be activated before channel 1.

If the inputs of the F127 are activated with external 24V_DC, the negative pole has to be connected to S21 (e.g. Light curtain applications). In those applications power supply on A1-A2 is only necessary to drive the Power-LED.

To control NC contacts from external contactors the feedback-loop should be connected in series between S12 and S34.

The relay is available with fixed or with removable terminals.