SD710 Series Servo Drive User Manual Chapter 5 Commissioning and Operation
10
Overload
detection time
Torque
command
100%
200%
Overl oad alarm
detec tion curv e
50%
Overl oad warni ng
detec tion
20% Overl oad
warni ng detect ion
Figure 5.11 Overload warning detection time diagram
The factory overload warning detection time is 20% of the overload alarm detection time. The overload warning detection
time can be changed by changing the overload warning value (Pn015). In addition, using it as an overload protection
function corresponding to the system used increases the safety of the system.
Example:
After changing the overload warning value (Pn015) from 20% to 50% as shown above, the overload warning
detection time is half the overload alarm detection time (50%).
(2) Transient and Continuous Overloads
By using the "Motor overload detection base current derating setting (Pn016)" to detect the overload alarm, the detection
time of the motor overload alarm can be shortened, and the detection time of the instantaneous overload alarm will be
changed accordingly.
Motor base current after rating reduction equals motor current threshold for starting the calculation of the overload alarm
(default is 1.15 times the motor) multiply motor overload detection base current derating setting(Pn016)
Example: With Pn016 set to 50% as shown in Figure 5.12, the overload alarm can be detected earlier because the motor
overload is calculated from 50% of the base current.
When the value of Pn018 is changed, the overload warning detection time is changed accordingly because the overload
warning detection current size is changed.
100%
200%
100%
Overl oad alarm
detec tion curv e
50%
Overload
detection time
Overl oad warni ng
detec tion
Torque
command
Figure 5.12 Motor overload alarm detection time diagram
An example graph of the overload curves for the drive and motor is shown in Figure 5.13. In the graph, the overload curve
for the motor (the two curves against the bottom) has an overload starting point of 115% and a critical point of 180% for
continuous and instantaneous overload; the overload curve for the drive (the two curves against the top) has a starting
point of 115% and a critical point of 170%.
