ABB ACS880-04F, Hardware Manual, Page: 61 / 172

Guidelines for planning the electrical installation 61
and form-wound non-ABB motors with nominal power smaller than 350 kW. For bigger
motors, consult the motor manufacturer.
Additional data for calculating the rise time and the peak line-to-line voltage
The diagrams below show the relative peak line-to-line voltage and rate of change of
voltage as a function of the motor cable length with and without a d
u /d t filter in use.
To calculate the actual peak voltage for a certain cable length read the relative Û
LL
/ U
N
value from the appropriate diagram and multiply it by the nominal supply voltage ( U
N
).
To calculate the actual voltage rise time for a certain cable length read the relative values
Û
LL
/ U
N
and (d u /d t )/U
N
from the appropriate diagram. Multiply the values by the nominal
supply voltage (U
N
) and substitute into equation t = 0.8 · Û
LL
/(d u /d t ).
Additional note for sine filters
Sine filters protect the motor insulation system. Therefore, the d u /d t filter can be replaced
with a sine filter. The peak phase-to-phase voltage with the sine filter is approximately
1.5 ·
U
N
.
Additional note for common mode filters
Common mode filters are available as plus code E208.
Nominal AC supply
voltage Requirement for
Motor insulation system ABB d u /d t filter, insulated N-end bearing and ABB
common mode filter
U
N
< 420 V Standard: Û
LL
= 1300 V + N + CMF
420 V < U
N
< 500 V Standard: Û
LL
= 1300 V + N + d u /d t + CMF
or
Reinforced: Û
LL
= 1600 V,
0.2 microsecond rise time
+ N + CMF
Drive with d u /d t filter Drive without d u /d t filter
I Motor cable length
Û
LL
/ U
N
Relative peak line-to-line voltage
d u /d t /U
N
Relative d u /d t value
Note : ÛLL and du/dt values are approximately 20% higher with resistor braking.
100 200 300
0.0
0.5
1.0
1.5
2.0
2.5
3.0
l (m)
du/dt
UN
-------------(1/

s)
Û
LL
/ U
N
Û
LL
/ U
N
l (m)
du/dt
UN
-------------(1/

s)
1.0
2.0
5.0
4.0
3.0
1.5
2.5
3.5
4.5
100 200 300
5.5