Mitsubishi Electronics MR-J2S- CL User Manual
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 (AL.50) occurs if overload operation performed is above the electronic
thermal relay protection curve shown in any of Figs 13.1. Overload 2 alarm (AL.51) 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.
from overloads. Overload 1 alarm (AL.50) occurs if overload operation performed is above the electronic
thermal relay protection curve shown in any of Figs 13.1. Overload 2 alarm (AL.51) 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.
1000
100
10
1
0.1
0
50
150
200
250
300
(Note) Load ratio [%]
O
perat
io
n t
im
e
[s
]
During rotation
During stop
100
a. MR-J2S-10CL to MR-J2S-100CL
1000
100
10
1
0.1
0
50
100
150
200
250
300
(Note) Load ratio [%]
O
perat
io
n t
im
e
[
s
]
During rotation
During stop
b. MR-J2S-200CL to MR-J2S-350CL
0
50
100
150
200
250
300
1
10
100
1000
10000
(Note) Load ratio [%]
Operat
io
n
t
im
e
[s
]
During rotation
During servo lock
c. MR-J2S-500CL MR-J2S-700CL
Note: If the servo motor is stopped or low-speed (30r/min or less) operation is performed at an abnormally high duty with torque more
than 100% of the rating being generated, the servo amplifier may fail even in a status where the electronic thermal relay protection
is not activated.
Fig 13.1 Electronic thermal relay protection characteristics