Characteristics; Overload Protection Characteristics - Mitsubishi Electric MR-J4W2-0303B6 Instruction Manual

10. CHARACTERISTICS

10. CHARACTERISTICS

10.1 Overload protection characteristics

An electronic thermal is built in the servo amplifier to protect the servo motor, servo amplifier and servo
motor power wires from overloads.
[AL. 50 Overload 1] occurs if overload operation performed is above the electronic thermal protection curve
shown in fig. 10.1 [AL. 51 Overload 2] occurs if the maximum current is applied continuously for several
seconds due to machine collision, etc. Use the equipment on the left-hand 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, the unbalanced torque
of the machine should be kept at 70% or less of the rated torque.
This servo amplifier has solid-state servo motor overload protection for each axis. (The servo motor overload
current (full load current) is set on the basis of 120% rated current of the servo amplifier.)
1000
100
Servo-lock
10
1
0.1
50 100
0
(Note 1, 2) Load ratio [%]
HG-KR053/HG-KR13
HG-MR053/HG-MR13
Note 1. 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 50 r/min or less low-speed operation status, the servo amplifier may malfunction
regardless of the electronic thermal protection.
2. The load ratio ranging from 300% to 350% applies to the HG-KR series servo motor.
3. The load ratio ranging from 350% to 400% applies to the HG-JR53 servo motor.
POINT
For the characteristics of the linear servo motor and the direct drive motor, refer
to sections 14.4 and 15.4.
Operating
150 200 250 300
Fig. 10.1 Electronic thermal protection characteristics
1000
100
10
1
0.1
350 0 50 100
(Note 1, 2, 3) Load ratio [%]
HG-KR23/HG-KR43/HG-KR73
HG-MR23/HG-MR43/HG-MR73
HG-SR51/HG-SR81/HG-SR52/HG-SR102
HG-JR53/HG-JR73/HG-JR103
10 - 1
Operating
Servo-lock
150 200 250 300
HG-UR72
350 400