ABB ACSM1 - Selection of DC Connection Fuses

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Selection of DC connection fuses
In the common DC system each DC connection must be equipped with
fuses. Fuses are needed in both branches (+ / -). Here are the general
guidelines for the selection of DC link fuses
• AC fuse class aR (so called high speed fuses) should be used.
• Fuse voltage rating should be 690 V
• Fuse nominal current
)i(ave,dcN,F
I.I ×≈ 61
where the average DC link current I
dc,ave
can be defined with
dc
)i(ave,dc
ave,dc
U
P
I =
• P
dc,ave(i)
is the maximum average (during the 3 min time
window) DC link power in the DC connection terminals of the
individual drive module.
• U
dc
is the actual DC link voltage
acdc
U.U ×≈ 351
The factor 1.6 covers the influence of cyclic load and ambient
conditions. If the average DC current I
dc,ave
is not exactly known the
power ratings of the drive module can be used. However the selected
fuse current rating and operation curve should be in line with the
used cable cross section to meet the regulations for the cable
protection.
The recommended fuse current ratings based of the DC power
ratings of drive modules are shown in the table below.
ACSM1-04xx- Fuse
Size
Frame
A
02A5-4 A 16
03A0-4 A 16
04A0-4 A 16
05A0-4
A
16
07A0-4
A
16
09A5-4
B
20
012A-4 B 32
016A-4
B
32
024A-4 C 63
031A-4
C
63
040A-4 C 100
046A-4
C
100
060A-4 D 160
073A-4 D 160
090A-4
D
160