Installing fuses for branch circuit protection – Rockwell Automation 23C PowerFlex 400 AC Drive Packages for Fan & Pump Apps User Manual
Page 186
186
Rockwell Automation Publication 23C-IN001B-EN-P - June 2013
Chapter 4
Electrical Installation
Observe these guidelines when installing an isolation transformer:
• A power disconnecting device must be installed between the power line
and the primary of the transformer.
• If the user-installed power disconnecting device is a circuit breaker, the
circuit breaker trip rating must be coordinated with the in-rush current (10
to 12 times full load current) of the transformer.
• Do not use an input isolation transformer rated more than 1000 kVA for
480 V AC (500 kVA for 208V AC) with less than 5% impedance directly
ahead of the drive without additional impedance between the drive and
the transformer.
shows recommended inductance and line reactor ratings.
Table 15 - AC Line Reactors
Installing Fuses for Branch Circuit Protection
If they were not installed as a factory option, install the required branch circuit
protection fuses according to the applicable local, national, and international
codes (such as NEC/CEC). The fuses must be installed in the line before the
drive input terminals.
Drive (Hp)
Line Reactor Inductance (±10%)
2…3
6.5 mH
5
3.0 mH
7.5
2.5 mH
10
1.5 mH
15
1.2 mH
20
0.8 mH
25
0.8 mH
30
0.7 mH
40
0.5 mH
50 to 60
0.4 mH
75
0.3 mH
100
0.2 mH
125
0.15 mH
150
0.11 mH
ATTENTION: Most codes require that upstream branch protection be provided
to protect input power wiring. Failure to observe this precaution could result
in severe bodily injury or loss of life.