Internal safe digital output F-DO_STO
The CS..A safety option has one internal safe digital output for switching the device-internal STO function of the basic device. The internal safe digital output is electrically connected to the STO terminals of the basic device. This is why you must not connect anything to the external terminals.
A maximum switching frequency of 10 Hz is permitted for the internal safe digital output. The switching state of the safe internal digital output must be stable on "1" or stable on "0" at least once within 60 seconds for at least 2 seconds (2.5 seconds with extended diagnostics).
The internal safe digital output F‑DO_STO is always operated in the connection type "two‑pole sourcing output" and must only be used for the STO function of the basic device. If the diagnostics implemented for the internal safe digital output F‑DO_STO detects a fault, the fault response "output fault" occurs, which disables the output.
Additional extended diagnostics can be activated for the internal safe digital output F‑DO_STO. If a fault is detected by diagnostics, the "output fault" fault response occurs, which disables the output.
The following settings can be made for extended diagnostics:
- Setting "Test when deactivated"
- If this setting is active, the functionality of diagnostics in the STO connection of the basic device is tested right after the STO function is deactivated.
- "Test when deactivated and time monitoring" setting
- This setting is identical to the "Test when deactivated" option. If diagnostics has not been performed within 8 hours, the safety option will additionally issue a warning. Time monitoring works properly only if the safety option deactivates the STO function before the diagnostics interval of 8 hours has elapsed. The test is not performed when switching on the safety option. Switching the safety option on/off cyclically is not allowed when using the time monitoring because when it is switched on again the time monitoring is reset and no test is performed. The safety option outputs a warning signal 8 hours after the last test after being switched on.
