Mitsubishi Electronics MDS-R ユーザーズマニュアル

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9. Adjustment 
 
 
 
 
 
9 - 30
 
(2)  Dynamic braking stop 
Dynamic braking stop takes place if an alarm for which dynamic braking stop is set as the stopping 
method occurs. With dynamic braking stop, the dynamic brakes activate simultaneously with the 
occurrence of an emergency stop. The motor brake control output also activates simultaneously. 
 
 
Emergency stop occurrence 
Time 
 
 
 
 
Motor speed
 
 
 
 
 
OFF
ON
Dynamic brake 
 
 
OFF
ON
Motor brake control output (MBU) 
 
 
 
 
 
CAUTION
 
The dynamic brakes cannot be used for normal braking. 
If the dynamic brakes activate continuously, the internal regenerative resistor 
could burn, so always eliminate the cause of the emergency stop before 
resuming operation. 
 
 
(3)  Deceleration control stop distance 
The stopping distance LEMG to stop the motor with deceleration control during an emergency stop 
can be approximated with the following expression. Note that the value will be higher than this if the 
current is limited during deceleration. Refer to section "3-2-3 (2) Coasting rotation distance during 
emergency stop" for the stopping distance when using dynamic brakes. 
 
F 1
F
F×EMGt 
LEMG = 
PGN1×60 
2
×
60
×
rapid×1000 
(mm)  
 
 
: Feedrate during emergency stop 
(mm/min) 
 
rapid 
: Rapid traverse rate 
(mm/min) 
 
PGN1 
: Position loop gain 1 
(SV003) 
(rad/s) 
 
EMGt 
: Deceleration time constant 
for emergency stop 
(SV056) (ms)