OSSD means "Output Switching Signal Device"

This output type is commonly used with safety sensors, safety light curtains, or for safe control outputs. Conventional 24 V DC outputs are actually crucial for safety functions because they cannot be detected by an external 24 V line via a short circuit. To adress this, the two OSSD outputs are switched off with a time delay. During the pause, a built-in input is activated and read back.

If 24 V is still present at the input after the output has been switched off, an error is detected and the two built-in processors safely switch off both outputs. This technology simplifies the monitoring of short circuits and cross circuits, achieving up to PLe compliance according to EN ISO 13849-1. With an advanced LED diagnostic system, as seen in the HOLDX R process guard locking devices or the SAFIX RFID safety sensors, faults on the safety sensor can be quickly identified, making troubleshooting significantly easier.