Simple Calculation Method - Delta Electronics ASDA-B Series User Manual

External load torque in reverse direction: TL* Wr
For the safety, we strongly recommend the users should select the proper resistance value according to
the load.
For example, when external load torque is a +70% rated torque and rotation speed reaches 3000 rpm, if
using 400W servo drive (rated torque: 1.27Nt-m), then the users need to connect a external
regenerative resistor which power is 2 × (0.7 × 1.27) × (3000 × 2 × π/ 60) = 560W, 40Ω.

Simple Calculation Method

The users can select the adequate regenerative resistors according to the allowable frequency required
by actual operation and the allowable frequency when the servo motor run without load. The allowable
frequency when the servo motor run without load is the maximum frequency that can be operated during
continuous operation when servo motor accelerate from 0rpm to rated speed and decelerate from rated
speed down to 0rpm. The allowable frequencies when the servo motor run without load are summarized
in the following table.
Allowable frequency when the servo motor run without load (times/min)
ECMA Series Power
Range
(Frame Size)
Allowable Frequency
(times/min)
ECMA Series Power
Range
(Frame Size)
Allowable Frequency
(times/min)
Revision January, 2009
Reverse
Forward
Rotation
Rotation
100W 200W
01 02
- -
1.0kW
900W
(100mm)
09 10
31 137
Chapter 6 Control Modes of Operation|ASDA-B Series
Motor Rotation Speed
External Load Torque
Motor Output Torque
Reverse
Rotation
TL : External load torque
400W 400W
300W
(60mm) (80mm)
03 04
- 1275
1.0KW 2.0kW
1.5KW
(130mm) (100mm)
10 15
42 31
Table 6.K
Forward
Rotation
500W 600W
04 05 06
519 43 41
2.0KW 2.0KW
(130mm) (180mm)
20 20 20
82 24 10
750W
07
319
6-35