Specifications

54
© 2005 Schneider Electric All Rights Reserved 11/2005
Power-Zone
®
4
Technical Overview
Selection Tables with Transformer Ratings
Transformer ratings for Masterpact NW circuit breakers in Power-Zone 4 switchgear are listed below.
Table 6: Application of Masterpact NW Circuit Breakers
(with Standard Three-Phase Transformers: Liquid Filled and Ventilated Dry Types)
Transformer Base
(100%) Rating
Secondary Short-Circuit Currents
RMS Symmetrical Amperes
Minimum Size Circuit Breakers
for Selective Trip Systems
kVA and
Percent
Impedance Amperes
a
Max.
Short-circuit
kVA Available
from Primary
System
Through
Transformer
Only
Motor
Contribution Combined
Main
Circuit
Breaker
Short-time
Delay Trip
Feeder
Circuit
Breaker
Short-time
Delay Trip
Feeder
Circuit Breaker
Instantaneous
Trip
208 V Three-Phase - 50% Motor Load / xd
" = 25%
b
300
5.0%
833
50000
100000
150000
250000
500000
Unlimited
14900
15700
16000
16300
16500
16700
1700
16600
17400
17700
18000
18200
18400
NW16N1
NW08N1
NW08N1
NW08N1
NW08N1
NW08N1
NW08N1
NT08N1
NW08N1
NW08N1
NW08N1
NW08N1
NW08N1
NW08N1
NT08N1
500
5.0%
1389
50000
100000
150000
250000
500000
Unlimited
23100
25200
26000
26700
27200
27800
2800
25900
28000
28800
29500
30000
30600
NW16N1
c
NW08N1
NW08N1
NW08N1
NW08N1
NW08N1
NW08H1
NT08N1
NW08N1
NW08N1
NW08N1
NW08N1
NW08N1
NW08H1
NT08N1
750
5.75%
2083
50000
100000
150000
250000
500000
Unlimited
28700
32000
33300
34400
35200
36200
4200
32900
36200
37500
38600
39400
40400
NW32H1
NW08N1
NW08N1
NW08N1
NW08N1
NW08N1
NW08N1
NT08N1
NW08N1
NW08N1
NW08N1
NW08N1
NW08N1
NW08N1
NT08N1
1000
5.75%
2778 50000 35900 5600 41500 N32H1
c
NW08N1
NT08N1
NW08N1
NT08N1
1000
5.75%
2778
100000
150000
250000
500000
Unlimited
41200
43300
45200
46700
48300
5600
46800
48900
50800
52300
53900
NW32H1
c
NW08H1
NW08H1
NW08H1
NW08H1
NW08H1
NW08H1
NW08H1
NW08H1
NW08H1
NW08H1