Chapter 2 Installation ASDA-B2
2-16 Revision May, 2018
(2) Simple Selection
Choose the appropriate regenerative resistor according to the allowable frequency and
empty load frequency in actual operation. The so-called empty allowable frequency is the
frequency of continuous operation when the servo motor runs from 0 r/min to the rated
speed and then decelerates from the rated speed to 0 r/min within the shortest time. The
following table lists the allowable frequency when the servo drive runs without load
(times/min).
Allowable Frequencies for Servo Motor Running Without Load (times/min)
When Using Built-in Regenerative Resistor
Motor Capacity
ECMA Series
600W 750W 900W 1.0kW 1.5kW 2.0kW 2.0kW 3.0kW
06 07 09 10 15 20 20 30
ECMAC
- 312 - 137 -
83
(F100)
-
ECMAE - - - 42 32
24
(F130)
10
(F180)
11
ECMAG 42 - 31 - - - - -
When the servo motor runs with load, the allowable frequency will be different
according to different load inertia or speed. The following is the calculation method.
m represents load / motor inertia ratio.
Allowable frequency =
Allowable frequency when servo motor run without load
m + 1
x
Rated speed
Operating speed
times
min.
2
The comparison table of external regenerative resistor is provided below. Please
choose the appropriate regenerative resistor according to the allowable frequency.
The table below describes the suggested allowable frequency (times/min) of
regenerative resistor when the servo drive runs without load.
Allowable Frequencies for Servo Motor Running Without Load (times/min)
When Using External Regenerative Resistor
Motor Capacity
Regenerative Resistor
ECMAC
100W 200W
400W
(F60)
400W
(F80)
750W 1.0kW 2.0kW
01 02 04 04 07 10 20
200W 80Ω 32793 6855 4380 1784 1074 458 273
400W 40Ω - - - - - 916 545
1kW 30Ω - - - - - - 1363