Mitsubishi Electric MELSERVO-JN Series, Инструкция по эксплуатации

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10 - 1
10. CHARACTERISTICS
10. CHARACTERISTICS
10.1 Overload protection characteristics
An electronic thermal relay is built in the servo amplifier to protect the servo motor, servo amplifier and servo
motor power lines from overloads.
Overload 1 alarm (50. ) occurs if overload operation that exceeds the electronic thermal relay protection curve
shown in Figs 10.1. is performed. Overload 2 alarm (51. ) occurs if the maximum current flows continuously
for several seconds due to machine collision, etc. Keep the load ratio within the area in the left side of the solid
line or the dotted line.
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. When closely mounting the servo amplifiers,
operate them at the ambient temperature of 0 to 45 (32 to 113 ) or at 75% or smaller effective load
ratio.
The servo motor overload protective function is built in MR-JN series servo amplifiers. (115% of the servo
amplifier rated current is set as standard (full load current).)
Oper
ation time[s]
1000
100
10
1
0.1
0 50 150 200 250 300 100
During operation
During servo lock
Oper
ation time[s]
1000
100
10
1
0.1
0 50 150 200 250 300
During operation
During servo lock
100
(Note) Load ratio [%] (Note) Load ratio [%]
MR-JN-10A (1) MR-JN-20A (1), MR-JN-40A
Note. If operation that generates torque equal to or higher than the rating is performed with an abnormally high frequency under servo
motor stop status (servo lock status) or in low-speed operation at 30r/min or less, the servo amplifier may malfunction even when
the servo system is used within the electric thermal protection area.
Fig 10.1 Electronic thermal relay protection characteristics