Sto State Monitor Output (Edm Signal) - Hitachi WJ Series User Manual

Chapter 14
14.1.2

STO State Monitor Output (EDM Signal)

 How to check the operation of STO function by enabling STO state monitor output (EDM
Q
signal)?
 When using STO state monitor output (EDM signal), turn ON EDM switch on the control circuit
A
terminal. "Output terminal [11] function [C021]" is automatically changed to "STO state monitor
output [EDM] (62)". At the same time, "Output terminal [11] active state [C031]" becomes "NO:
Normally Open (00)".
 STO state monitor output (EDM signal) is a reference signal for monitoring the input status of
STO signal and failure detection status of the internal safety path. It is not permitted to activate
the safety function using this signal.
Control circuit
terminal
EDM switch
 Refer to the signal matrix in the table below for the
 operation of EDM signal for [ST1]/[ST2] and failure detection status. EDM signal turns ON only
when both STO inputs are correctly input and internal failure is not detected.
Signal
*1
[ST1]
*1
[ST2]
Failure
detection
[EDM]
Output to
the motor
*1. Correspondence between the input status of [ST1]/[ST2] and
the contact status: Operation permitted = contact ON, STO = contact OFF
 When the EDM switch is ON, input terminals 3 and 4 of "Input terminal monitor [d005]" indicate
!
the status of [ST1]/[ST2], respectively. For details, see section "10.2.1 Monitor the Status of
Input and Output Terminals".
 When EDM switch is turned OFF from ON, "Output terminal [11] function [C021]" is
automatically changed to "No assignment (no)".
■ STO timing chart
 The timing chart of the output to the motor and EDM signal for STO input [ST1]/[ST2] is shown
below. The output to the motor is shut off within 20 ms after [ST1] and [ST2] are turned off.
ON
OFF
Status 1 Status 2
Operation
STO
permitted
STO STO
None None
ON OFF
Shut off Shut off
[ST1]
[ST2]
Output to the motor
[EDM]
STO state monitor output
CM2
Status 3 Status 4
Operation
STO
permitted
Operation Operation
permitted permitted
None None
OFF OFF
Output
Shut off
permitted
ON OFF
ON
OFF
Off
Output
ON
OFF
20 ms
30 ms
14-1-3
Safety Function STO
12 11
Load
Status 5
STO or Operation
permitted
STO or Operation
permitted
Detected
OFF
Shut off