F142 Safety Relay  

E-Stop Relay and Safety Gate Monitor
Stop Category 0
Safety Category 4
7 N/O safety contacts
4 N/C signaling contacts
2 solid-state aux. outputs
6 diagnostic LEDs
Cross-fault monitoring
Monitored or automatic reset
Suitable for light curtain
and safety mat applications
Removable terminal blocks

DIN En60204 Part 1 / VDE0113 Part 1 prescribes that power circuits with a safety function must be specified as per Section 9.4.

The F142 Safety Relay fulfills these requirements in accordance with EN 954-1 up to the highest Safety Category 4.

The protection function must be activated at least once every 6 months, to confirm its operational condition.

The F142 can be used in 1- or 2-channel applications, with or without cross-fault monitoring.

It is put into operational state either by closing the external “Start” switch, or automatically on power-up.

The diagnostic LEDs indicate the states of the power supply input, the „Start“ switch, the emergency stop contacts and the output relays.

The solid-state switch output Y35 is activated by the closing of the emergency stop circuit, and the Y32 output by the energization of one or more of the output relays.

  Mode of Operation

Cross-fault protection is implemented with 2-channel control as shown in external circuit examples 1 through 3 (see next page). This means the actuation of a safety mat with 4-wire connection or line termination will result in electronic safety action that turns off the F142. All LEDs will turn off while a cross-fault exists, except the „PWR“ LED which blinks during this




time. The F142 reverts automatically to normal operating mode when the fault is cleared.

In monitored reset mode, the „Reset“ switch is interrogated for a leading edge each time the unit is switched on. A reset is not possible if the „Reset“ switch is closed before the emergency stop contacts are opened, or before the power supply is switched on.

If the unit is in auto-reset mode (terminals X1-X2, X3-X4 and S33-S34 shorted), it turns on automatically as soon as the emergency-stop and feedback circuits are closed.

In auto-reset mode, if the emergency-stop circuits are not closed simultaneously, then the Channel 2 circuit must be closed before the Channel 1 circuit (e.g. safety gate monitoring).

If inputs (external contacts) are interrogated using an external 24 VDC supply, its negative potential (0 VDC) must be connected to terminal S21 (e.g., in light curtain applications).


The solid-state outputs can be used to coordinate the F142 with a PLC directly.
If a contactor is used with the F142, a pair of N/C contacts of the former must be connected to terminals Y1-Y2 (feedback circuit).

The F142 is reset by closing the feedback circuit.

The F142 has removable screw-terminal blocks for easy installation.

  Models and Ordering Data


Technical Data / Overview Safety Relays

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