6 | Project configuration
STOBER
54
05/2019 | ID 442790.01
6.2.2
Design
Charging capacity
The charging circuit integrated into a drive controller can charge the DC links of other drive controllers in addition to its own
DC link.
Information
When designing the Quick DC-Link, note that the sum of the charging capacities of the drive controllers connected to the
grid is greater than or equal to the sum of the self-capacitances of all drive controllers in the DC link group.
Example – Checking the charging capacity of drive controllers connected to the grid
A SC6A261 drive controller connected to the grid is intended to charge another SC6A261 drive controller.
The DC link capacitance in the group to be charged corresponds to the sum of the self-capacitance values of all drive
controllers in the group: 2 × 940 μF = 1880 μF.
The maximum charging capacity of the drive controller connected to the grid is 1400 μF.
Information
If a time span of ≥ 15 min is maintained between energizing two devices, the maximum charging capacity C
maxPU
increases to
1880 μF.
In this case, Quick DC-Link is permitted only if the minimum time of 15 min between energizing two devices is maintained.
Current load capacity of the input rectifiers
Information
When designing the Quick DC-Link, note that the required supply current does not exceed the maximum supply current in
total.
minLINE
m axLINE
I
I
<
For calculating the effective as well as maximum supply current, SERVOsoft is helpful mechanical and electrical design
software for drive systems.
Calculating supply current for motors
The necessary supply current for motors can be determined using the required drive output:
LINE
totalMOT
P
P
@
