Mitsubishi Electric MR-J4W2-0303B6, Instruction Manual

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10. CHARACTERISTICS
10 - 5
10.3 Dynamic brake characteristics
CAUTION
The coasting distance is a theoretically calculated value which ignores the
running load such as friction. The calculated value will be longer than the actual
distance. If an enough braking distance is not provided, a moving part may crash
into the stroke end, which is very dangerous. Install the anti-crash mechanism
such as an air brake or an electric/mechanical stopper such as a shock absorber
to reduce the shock of moving parts.
POINT
Do not use dynamic brake to stop in a normal operation as it is the function to
stop in emergency.
For a machine operating at the recommended load to motor inertia ratio or less,
the estimated number of usage times of the dynamic brake is 1000 times while
the machine decelerates from the rated speed to a stop once in 10 minutes.
Be sure to enable EM1 (Forced stop 1) after servo motor stops when using EM1
(Forced stop 1) frequently in other than emergency.
Servo motors for MR-J4 may have the different coasting distance from that of
the previous model.
The electronic dynamic brake operates in the initial state for the HG series servo
motors of 600 [W] or smaller capacity. The time constant "
τ " for the electronic
dynamic brake will be shorter than that of normal dynamic brake. Therefore,
coasting distance will be longer than that of normal dynamic brake. For how to
set the electronic dynamic brake, refer to [Pr. PF06] and [Pr. PF12].