Monitoring Inputs are “fault” bits for each channel. Some position encoders will generate a fault signal to let the automation know the signal is not good (should not be used).

In the CFC software you can use the NAV block from library "SIMATIC TDC/SIMADYN D/FM458-1 DP/ T400" to see this input as well as the position feedback. The monitoring input will bedisplayed on output QF (It does not use this input to fault the NAV block or the position output, it is only used for display purposes). By Addressing the NAVblock to the specific encoder it automatically knowsto use the corresponding"Monitoring Input" to set its "QF" output.

On our system we have TTL (5V) incremental encoder pulse waves. However, the Monitoring Input will only accept 15V binary signals to activate them. We have to add 1k Ohm pull up resistors between the encoder's 5V fault output, the SU13's Monitoring Input,and the SU13's 15V Encoder Power. For example, if we are using the monitoring input for Incremental Encoder #1 the encoder is tied to terminals 1-4. And our encoder fault signal is tied to Monitoring input #1 at terminal 21 on the SU13. We add one additional resistor (1k) between the SU13’s terminals 21 and 50.