Setting For Emergency Stop; Vertical Axis Drop Prevention Control - Mitsubishi Electric MELDAS MDS-B Series Instruction Manual

10-4 Setting for emergency stop

10-4-1 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 servo ready OFF will be
delayed by the time set in the parameter from when the emergency stop occurs. Thus, the no-control
time until the brakes activate can be eliminated.
POINT
(1) Working conditions
1) Emergency stop input
2) CNC power OFF
the
(when drive section power is ON)
3) When alarm occurs
according
4) Input power OFF
(instantaneous power failure, etc.)
of
voltage
CAUTION
(2) Outline of function, and setting of parameters
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When stopped
During movement
No. Abbrev. Name
SV048 EMGrt Vertical axis drop
prevention time (ms)
SV055 EMGx Emergency stop
max. delay time
(ms)
SV056 EMGt Time constant for
deceleration control
during emergency
stop
Chapter 10 Adjustment
The CN20 connector on the servo drive unit can be used for mechanical brake
control. Refer to section "7-2-12 Connection with mechanical brakes" for details
on the connection with mechanical brakes.
Note that drop prevention may not be possible in all conditions as noted above. To
prevent dropping in all conditions, use a balance unit on the machine side, etc.
The driver's READY is turned OFF after the vertical axis drop prevention
time (SV048) has passed.
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Deceleration stop is carried out, and then the driver's READY is turned
OFF after the longer of the vertical axis drop prevention time (SV048) or
emergency stop max. delay time (SV055) has passed.
Set the READY OFF delay time at an emergency stop. Set a larger
value than the brake operation time.
When the input power is OFF, the set vertical axis drop prevention time
may not necessarily be guaranteed.
Set the max. READY OFF delay time.
Normally, the same value as SV048 is set.
To turn READY OFF after decelerating to a stop, set the same value as
SV056. Note that this is valid when SV056 is larger than SV048.
If a value smaller than SV048 is input in the parameters, the same
value as SV048 will be automatically set.
When the input power is OFF, the set max. READY OFF time may not
necessarily be guaranteed.
When SV048 is set, deceleration stop is carried out during movement,
so set this deceleration stop time constant.
Set the same value as the rapid traverse time constant.
When this parameter is set, constant inclination linear deceleration stop
will be carried out at the emergency stop.
If 0 is set, step stopping will be carried out.
: The drive side detects the emergency stop input
signal, and enters this function mode.
: The driver detects the power OFF message from
CNC, and enters this operation.
: Note that the activity of this function differs
to the alarm. (Refer to the Table of driver alarm
classes)
: Normally, the CNC power OFF signal is detected by
the drive side, and this operation is entered in the
same manner as item 2). However, in this mode
where the input power is suddenly shut off, there
may be no effect depending on the operation state
the axis supplied power from the input power
and power supply (axis connected with L+, L–).
Details
10–25
Setting range
0 to 2000
(ms)
0 to 2000
(ms)
0 to 2000
(ms)