... how OSSD outputs work?
OSSD means "Output Switching Signal Device"
This output type is typically used with safety sensors and safety light curtains or for safe control outputs. Conventional 24 V DC outputs are actually critical for safety functions, as they cannot be detected by an external 24 V line via a short circuit. For this reason, the two OSSD outputs are switched off with a time delay. During the pause time of the output, a built-in input is activated and read back.
If 24 V is present at the input after switching off the output, an error is detected and the two built-in processors safely switch off both outputs. This technology makes it easy to monitor short circuits and cross circuits up to PLe according to EN ISO 13849-1. With the aid of an extended LED diagnosis, such as on the HOLDX R process guard locking or the RFID safety sensors of the SAFIX, the detected faults on the safety sensor can be quickly detected and make troubleshooting considerably easier.