Planning – basics 23
Checking the total charging resistance
Use this method for verifying the charging capacity if there are only drives with
charging circuits in the common DC system.
The total charging resistance must comply with this formula:
R
tot
>
R
min
Calculate the value
R
tot
as follows:
Define the value
R
min
as follows:
1. If you connect only one drive to the AC power line,
R
min
is equal to the minimum
charging resistance defined for that drive. See section
on
page
.
2. If you connect several drives to the AC power line, calculate
R
min
. Use this equation:
R
tot
Calculated total charging resistance for the common DC system.
R
min
Minimum charging resistance allowed for the common DC system.
R
a
Charging resistance of drive a in the common DC system. See section
on page
R
b
Charging resistance of drive b in the common DC system. See section
on page
R
min,1
Minimum charging resistance of drive 1 connected to the AC power line. See section
on page
.
R
min,2
Minimum charging resistance of drive 2 connected to AC power line. See section
on page
R
tot
R
a
1
R
b
1
R
n
1
+
+
+
1
=
…
R
min
R
min,1
1
R
min,2
1
R
min,n
1
+
+
+
1
=
…
Summary of Contents for ACS880-04 drive modules
Page 4: ......
Page 10: ...10 Introduction to the manual...
Page 16: ...16 Operation principle and hardware description...
Page 30: ...30 Planning basics...
Page 38: ...38 Planning additional instructions...
Page 48: ...Contact us www abb com drives www abb com drivespartners 3AUA0000127818 Rev B EN 2014 04 17...
