Mitsubishi Electric MELSERVO MR-J3-xT, Instruction Manual

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13 - 1
13. CHARACTERISTICS
13. CHARACTERISTICS
13.1 Overload protection characteristics
An electronic thermal relay is built in the servo amplifier to protect the servo motor and servo amplifier from
overloads. Overload 1 alarm (A50) occurs if overload operation performed is above the electronic thermal relay
protection curve shown in any of Figs 13.1. Overload 2 alarm (A51) occurs if the maximum current flew
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.
In a machine like the one for vertical lift application where unbalanced torque will be produced, it is
recommended to use the machine so that the unbalanced torque is 70% or less of the rated torque.
When you carry out adhesion mounting of the servo amplifier, make circumference temperature into 0 to 45 ,
or use it at 75% or a smaller effective load ratio.
Servo amplifier Graph
MR-J3-10T (1) Fig 12. 1 a
MR-J3-20T (1) MR-J3-40T (1)
MR-J3-60T to MR-J3-100T
Fig 12. 1 b
MR-J3-200T Mr-J3-350T Fig 12. 1 c
MR-J3-500T MR-J3-700T Fig 12. 1 d
MR-J3-11KT to MR-J3-22KT Fig 12. 1 e
1000
100
10
1
0.1
0 50 150 200 250 300 100
(Note) Load ratio [%]
O
p
er
at
ion t
ime[
s]
During operation
During servo lock
a. Electronic thermal relay
protection
characteristics1
1000
100
10
1
0.1
0 50 150 200 250 300 100
(Note) Load ratio [%]
O
perat
io
n
ti
m
e
[s
]
During operation
During servo lock
b. Electronic thermal relay
protection characteristics2
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 fail even when the
electronic thermal relay protection is not activated.
Fig 13.1 Electronic thermal relay protection characteristics (1/2)