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MDS-D-SVJ3/SPJ3 Series Instruction Manual
4-6 Settings for emergency stop
4-6-2 Vertical axis drop prevention control
The vertical axis drop prevention control is a function that prevents the vertical axis from dropping due to
a delay in the brake operation when an emergency stop occurs. The no-control time until the brakes
activate can be eliminated by delaying the servo READY OFF state by the time set in the parameters
when an emergency stop occurs.
Always use this function together with deceleration control.
<Setting procedures>
[1] Apply emergency stop while viewing the current position on the NC screen. Adjust the vertical axis
drop prevention time (SV048), and set the 1.5-fold minimum delay time at which the axis does not
drop.
When using a motor with a break, confirm that the axis will not drop at the 150ms setting, and set
200ms.
[2] Set the value of the normal acceleration/deceleration time constant plus 100ms for the max. gate
off delay time at emergency stop (SV055), and standard setting value of the axis for the
deceleration control time constant at emergency stop (SV056). Refer to "4-6-1 Deceleration
control" for details.
[3-1] When the contactor is controlled by the MDS-D-SVJ3 unit, to which the vertical axis drop
prevention control is set
The parameter setting is completed.
[3-2]When the contactor of MDS-D-SVJ3, to which the vertical axis drop prevention control is set, is
controlled by the MDS-D-CV unit
Set the spindle parameters SP055 and SP056 of the spindle drive unit that controls the MDS-D-CV
unit.
[3-3]When the contactor of the MDS-D-SVJ3 unit, to which the vertical axis drop prevention control is
set, is controlled by the MDS-D-SPJ3 unit
Set the spindle parameters SP055 and SP056 of the MDS-D-SPJ3 unit.
ON
ON
ON
ON
OFF
OFF
OFF
OFF
SV048
Emergency stop (EMG)
Motor brake control output (MBR)
Motor brake actual operation (BRK)
Servo READY (READY)
Vertical axis drop prevention control sequence