ABB ACS320 series, Руководство пользователя

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388 Technical data
Fuses and alternate short-circuit protection

Fuses
The rated fuse currents given in the table are the maximums for the mentioned
fuse types.
If smaller fuse ratings are used, check that the fuse rms current rating is
larger than the rated I
1N
current given in the Ratings table on page 384 . If 150% of
output power is needed, multiply current I
1N
by 1.5. See also section Selecting the
power cables on page 37 .
Check that the operating time of the fuse is below 0.5 seconds . The operating
time depends on the fuse type, the supply network impedance as well as the cross-
sectional area, material and length of the supply cable. In case the 0.5 seconds
operating time is exceeded with the gG or T fuses, ultra rapid (aR) fuses reduces in
most cases the operating time to an acceptable level.
Note:
• Do not use larger fuses when the input power cable is selected according to this
table.
• Choose the correct fuse size according to the actual input current which depends
on the input line voltage and the input choke selection.
• You can use other fuse types if they meet the current rating of the fuse in the table
and also if the melting curve of the other fuses does not exceed the melting curve
of the fuse in the table.

Alternate short-circuit protection
In accordance with the National Electrical Code (NEC), the following ABB type E
manual motor protectors can be used as an alternate to the recommended fuses as a
means of branch circuit protection:
• MS132-x.x and S1-M3-25
• MS495-xx or MS495-xxE and SK4-11 & DX49
• MS165-xx.
When the correct ABB type E manual motor protector is selected from the table and
used for branch circuit protection, the drive is suitable for use in a circuit capable of
delivering not more than 65 kA RMS symmetrical amperes at the drive maximum
rated voltage. See the appropriate ratings in the following table.
IP20 open type and IP21 UL type 1 ACS320 can use ABB type E manual motor
protectors for branch circuit protection. See the MMP rating table for the minimum
enclosure volume of IP20 open type ACS320 mounted in an enclosure.