Characteristics - Mitsubishi Electric MR-J4-10A(-RJ) Instruction Manual

15. USING A LINEAR SERVO MOTOR

15.4 Characteristics

15.4.1 Overload protection characteristics
An electronic thermal is built in the servo amplifier to protect the linear servo motor, servo amplifier and
linear 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. 15.2. [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-side area of the continuous or broken
line in the graph.
Use the linear servo motor with 70% or less of the effective load ratio when it is in the servo lock state or in a
small reciprocating motion.
This servo amplifier has solid-state linear servo motor overload protection. (The servo motor overload
current (full load current) is set on the basis of 120% rated current of the servo amplifier.)
1000
100
10
Servo-lock
1
0.1
0 50 100
a. LM-H3 series
LM-K2 series
1000
100
10
Servo-lock
1
0.1
0 100 200
c. LM-F series (natural cooling)
Operating
150 200 250
Load ratio [%]
Operating
300 400 500
Load ratio [%]
Fig. 15.2 Electronic thermal protection characteristics
1000
100
10
1
0.1
0 100
300
1000
100
10
1
0.1
600 0 50
d. LM-F series (liquid cooling)
15 - 28
Operating
Servo-lock
200 300
Load ratio [%]
b. LM-U2 series
Operating
Servo-lock
100 150 200
Load ratio [%]
400
250 300