2 instantaneous contacts:
	Stop Category 0,
	Safety Category 4
	3 off-delayed contacts:
	Stop Category 1,
	Safety Category 3
	Cross-fault monitoring
	Monitored or automatic start
	Suitable for use with light curtains
	Plug-in terminal blocks

Electrical sub-systems of industrial machinery must incorporate safety circuits as defined by Clause 9.4 of DIN EN 60204 (Part 1) / VDE 0113 (Part 1).

The Emergency Stop Relay F138 fulfills these requirements in accordance with EN 954-1.

It can be used in 1- or 2-channel applications, with or without cross-fault monitoring.

The F138 is put into operational state either by closing the external re-set contact, or by wiring the unit for automatic re-set (see wiring diagrams on the next page).

When the power supply is switched on and the emergency stop, feedback, and re-set circuits are closed, the unit is ready for operation. The ready state is indicated by the "PWR" LED lighting up. After the re-set contact is closed, the unit's safety relays are energised and the corresponding relay status LEDs light up. When an emergency stop circuit is opened, the relays CH1 and CH2 are de-energised immediately, the corresponding relay status LEDs are extinguished and the lapse of time begins. Following the delay-off period the relays CHT1 and CHT2 de-energise and their corresponding status LEDs estinguish. During delay timing, the delayed

contacts can be caused to be opened by opening the re-set circuit across terminals Y39-Y40. In monitored start mode, the re-set circuit is interrogated each time the unit is switched on. If the re-set contact is closed before opening of the emergency stop contacts, or before switching on the power supply, the unit cannot enter into the "ready" state (i.e., it cannot be re-set). In auto-start mode (terminals X1-X2 and X3-X4 shorted), the unit becomes operational immediately upon the power supply being switched on, if the emergency stop, feedback, and re-set circuits are closed.
If both emergency stop contacts are not closed simultaneously, the Channel 2 circuit must be closed before Channel 1 (e.g. in protective door monitoring applications).

If inputs are activated via external 24 VDC supply, the negative potential (0 VDC) must be connected to terminal S21 (Only 24V-versions, e.g., in light curtain applications with PNP output).

When an external contactor is used with

the F138, normally-closed contacts must be connected across terminals Y1-Y2 (feedback circuit).

If no external contacts are to be monitored, or delayed re-set is not to be used, then terminals Y1-Y2 and Y39-Y40 (respectively) should be shorted.

The F138 is equipped with plug-in screw-terminal blocks for easy installation.