External Device Monitor (Edm1) - YASKAWA SGMJV User Manual

If the application frequently uses the HWBB function, do not use the dynamic brake to stop the motor, or otherwise
element deterioration in the SERVOPACK may result. Use a sequence in which the HWBB state occurs after the ser-
vomotor has come to a stop.
(10) Position Error Clear Section
A position error in the HWBB state is cleared according to the setting in Pn200.2 for the clear operation selec-
tion.
If Pn200.2 is set to 1 (i.e., the position error is not cleared for position control), the position error pulses will
be accumulated unless the position reference from the host controller is canceled in the HWBB state, and the
following condition may result.
• A position error pulse overflow alarm (A.d00) occurs.
• If the servo is turned ON after changing from HWBB state to BB state, the motor will move for the accumu-
lated position error.
Therefore, stop the position reference through the host controller while in HWBB state. If Pn200.2 is set to 1
(i.e., the position error is not cleared), input the clear (CLR) signal while in HWBB or BB state to clear the
position error.
(11) Servo Alarm Output Signal (ALM) and Alarm Code Output Signals (ALO1, ALO2,
and ALO3)
In the HWBB state, the servo alarm output signal (ALM) and alarm code output signals (AOL1, AOL2, and
AOL3) are not sent.

5.11.2 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.
Signal
Name
/HWBB1
ON
/HWBB2
ON
EDM1
OFF
Failure Detection Signal for EDM1 Signal
Detection of failures in the EDM1 circuit can be checked using the following four status of the EDM1 signal
in the table. Failures can be detected if the failure status can be confirmed, e.g., when the power supply is
turned ON.
The EDM1 signal is not a safety output. Use it only for monitoring a failure.
CAUTION
Logic
ON OFF
OFF ON
OFF OFF
WARNING
When both /HWBB1 and /
HWBB2 signals are OFF,
EDM1 signal turns ON.
OFF
OFF
ON
5.11 Safety Function
5
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