Safety Light Curtain – C4 compact ME Series
Installation Guide
File Number: CD1011
page 17 Date: 12 April, 2017
depend on the customer’s risk assessment for the machine.
The Yellow wire on the Receiver (RX) head cable must be connected to 0V DC (L-) and the
Green wire on the Receiver (RX) head to the 24V DC (L+).
External Device Monitoring (EDM)
An External Device Monitoring input facility is provided for monitoring the external Final
Switching Devices (FSD) to ensure those devices respond in unison with the safety outputs each
and every time the safety light curtain is interrupted. Failure of the external Final Switching
Device during monitoring will not allow the safety light curtain to reset.
In Auto reset mode the EDM function is connected via the Green wire on the Receiver (RX) head
via a normally closed (NC) contact of the external final switching device (FSD) being monitored.
The other side of the contact(s) is connected to 24V DC.
If the EDM is not being used the Green wire must be connected to a permanent 24V DC (L+).
The bottom yellow LED indicator located on the Receiver (RX) head shows the EDM status.
Safety Outputs OSSD1 and OSSD2
Two independent (PNP) electronic switching failsafe signal outputs (OSSDs) are provided for the
machine safety circuit. Interruption of the safety light curtains infrared sensing field will cause
the OSSDs to go to an OFF state and initiate a machine stop condition.
The connections are provided via the Grey wire (OSSD1) and the Orange wire (OSSD2) on the
Receiver (RX) head cable.
Outputs ON = +24V DC (Light curtain clear)
Outputs OFF = 0V DC (Light curtain blocked)
The electronic outputs are monitored and rated at a maximum switching rating of 24V DC,
500mA. LED indicators located on the Receiver (RX) head show the status of the OSSDs.
Green LED ON = OSSD1 and OSSD2 active ON
Red LED ON = OSSD1 and OSSD2 inactive OFF
Yellow LED ON = EDM ON
Yellow LED OFF = EDM OFF
