ABB ACS850 - Multiple AC Input; Charging Current

22
R values (R
1
, R
2
,…) are the charging resistances of each drive module.
The following condition must be fulfilled:
• R
tot
> R
min
If the condition cannot be fulfilled, more than one drive module must be connected to
the AC supply.
Multiple AC input
Define R
tot
as in the previous case. Define the effective total minimum resistance as
follows:
•
nminmin
min
RRR
R
111
1
21
+++
=
L
R
min
values (R
min1
, R
min2
,…) are the individual minimum resistance values of the drive
modules connected to the AC supply.
The following condition must be fulfilled:
• R
tot
> R
min
Charging current
A typical AC input line current waveform and the DC link voltage during charging are
shown in the figure below.
Check that the AC supply side components (fuses, contactors, etc.) can withstand the
peak current.
The peak current I
ac,peak
is calculated as follows:
•
tot
ac
peak,ac
R
U
I
×
=
2
Common DC configurations