Yaskawa Sigma-5 User Manual: Design and Maintenance - Rotary Motors - Manual (Page 132)

4.6 Safety Function
4-49
Operation
4.6.2 External Device Monitor (EDM1)
The external device monitor (EDM1) functions to monitor failures in the HWBB function. Connect the moni-
tor to feedback signals to the safety unit. The relation of the EDM1, /HWBB1, and /HWBB2 signals is shown
below.
Failure Detection Signal for EDM1 Signal
Detection of failures in the EDM1 circuit can be checked using the status of the 3 signals in the table. Failures
can be detected if the failure status can be confirmed, such as when the power supply is turned ON.
Signal
Name
Logic
/HWBB1 ON ON OFF OFF
/HWBB2 ON OFF ON OFF
EDM1 OFF OFF OFF ON
When both /HWBB1 and /
HWBB2 signals are OFF,
EDM1 signal turns ON.
WARNING
The EDM1 signal is not a safety output. Use it only for monitoring a failure.