Mitsubishi Electric MELSERVO-J3W Series, Instruction Manual

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15. MR-J3W-0303BN6 SERVO AMPLIFIER
15 - 53
15.8 Characteristics
POINT
This section does not include the following items. For details of the items, refer to
each section of the detailed description field.
Item
Detailed
explanation
Cable bending life Section 10.4
15.8.1 Overload protection characteristics
An electronic thermal is built in the servo amplifier to protect the servo motor, servo amplifier and servo motor
power lines from overloads.
Overload 1 alarm (50. ) occurs if overload operation performed is above the electronic thermal protection curve
shown in fig. 15.1. Overload 2 alarm (51. ) occurs if the maximum current is applied continuously for several
seconds due to machine collision, etc. Use the equipment on the left-side area of the continuous or broken line
in the graph.
For the system where the unbalanced torque occurs, such as a vertical axis system, it is recommended that the
unbalanced torque of the machine be kept at 70 or less of the motor's rated torque. When mounting MR-J3W-
40303BN6 closely, use it with 75 or lower effective load ratio.
The MR-J3W servo amplifiers have servo motor overload protection function for each axis. (The servo motor
overload current (full load current) is set on the basis of 115 rated current of the servo amplifier.)
Operat
ion t
im
e [
s]
0.1
100 200 300 0 50 150 250
1000
100
10
1
In servo lock
In operation
(Note) Load ratio [ ]
HG-AK0136/0236/0336
Note. If operation that generates torque more than 100 of the rating is performed with an
abnormally high frequency in a servo motor stop status (servo-lock status) or in a
30r/min or less low-speed operation status, the servo amplifier may malfunction
regardless of the electronic thermal protection.
Fig. 15.1 Electronic thermal protection characteristics