Omron R88M-K - 3-2 Overload Characteristics (Electronic Thermal Function)

3-35
3 Specifications
G5-series AC Servomotors and Servo Drives User’s Manual (with Built-in EtherCAT Communications)
3-2 Overload Characteristics (Electronic Thermal
Function)
3
3-2-1 Overload Characteristics Graphs
3-2 Overload Characteristics (Electronic
Thermal Function)
An overload protection function (electronic thermal) is built into the Servo Drive to protect the drive and
motor from overloading. If an overload does occur, first eliminate the cause of the error and then wait at
least 1 minute for the motor temperature to drop before turning ON the power again.
If the error reset is repeated at short intervals, the motor windings may burn out.
The following graphs show the characteristics of the load ratio and electronic thermal function's
operation time.
When the torque command = 0, and a constant torque command is continuously applied after 3 or more
times the overload time constant has elapsed, the overload time t [s] is
t [s] = −Overload time constant [s] × log
e
(1 − Overload level [%] / Torque command [%])
2
(The overload time constant [s] depends on the motor. The standard overload level is 115%.)
3-2-1 Overload Characteristics Graphs
100
0.1
1
10
100
150 200 250 300
Torque [%]
115
Time [s]
50 W
100 W (100 V)
100 W (200 V)
200 W
400 W
750 W
3,000-r/min Servomotors
[100 V, 200 V]
100
115
0.1
1
10
100
150 200 250 300 Torque [%]
Time [s]
[200 V]
3,000-r/min Servomotors 1.0 kW to 5 kW
2,000-r/min Servomotors
1.500-r/min Servomotors
1,000-r/min Servomotors
[400 V]
3,000-r/min Servomotors
2,000-r/min Servomotors
1.500-r/min Servomotors
1,000-r/min Servomotors