YASKAWA A1000 Technical Manual page 602

D.4 Safe Disable Input Function
Returning to Normal Operation after Safe Disable
The Safe Disable function can only be deactivated when a Run command is not active.
When Safe Disable was activated during stop, normal operation can be resumed by simply turning on both Safe Disable
inputs (i.e., by deactivating "Safe Torque Off").
When Safe Disable was activated during run, first the Run command has to be removed and then the Safe Disable inputs
have to be turned on before the drive can be restarted.

Safe Disable Monitor Output Function and Digital Operator Display
Table D.14 explains the drive output and Safe Disable monitor state depending on the Safe Disable inputs.
Safe Disable Input Status
Input 1, H1-HC
OFF
ON
OFF
ON
Safe Disable Status Monitor
With the Safe Disable monitor output (terminals DM+ and DM-), the drive provides a safety status feedback signal. This
signal should be read by the device that controls the Safe Disable inputs (PLC or a safety relay) in order to prohibit
leaving the "Safe Torque Off" status in case the safety circuit malfunctions. Refer to the instruction manual of the safety
device for details on this function.
Digital Operator Display
When both Safe Disable inputs are open, "Hbb" will flash in the digital operator display.
Should only one of the Safe Disable channels be on while the other is off, "HbbF" will flash in the display to indicate that
there is a problem in the safety circuit or in the drive. This display should not appear under normal conditions if the Safe
Disable circuit is utilized properly.
possible errors.
602
Table D.14 Safety Input and EDM Terminal Status
Safe Disable Status Monitor,
S6 Selected
Input 2, H2-HC
N.C.
OFF OFF
OFF ON
ON ON
ON ON
Refer to Alarm Codes, Causes, and Possible Solutions on page 350
YASKAWA ELECTRIC SIEP C710616 27G YASKAWA AC Drive A1000 Technical Manual
DM+ - DM-
Drive Output Status
S6 Selected
N.O.
ON Safely disabled, "Safe Torque Off"
OFF Safely disabled, "Safe Torque Off"
OFF Safely disabled, "Safe Torque Off"
OFF Baseblock, ready for operation
Digital Operator Display
Hbb (flashes)
HbbF (flashes)
HbbF (flashes)
Normal display
to resolve