Characteristics; Overload Protection Characteristics - Mitsubishi Electric MELSERVO-J4 Instruction Manual

10. USING A LINEAR SERVO MOTOR

10.2 Characteristics

10.2.1 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. 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-side area of the continuous or broken
line in the graph.
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
0 100 200
a. LM-F (natural cooling)
Operating
300 400 500
Load ratio [%]
Fig. 10.1 Electronic thermal protection characteristics
1000
100
10
Servo-lock
1
0.1
600 0 50
b. LM-F (liquid cooling)
10 - 4
Operating
100 150 200
Load ratio [%]
250 300