GE AKR-30S, Руководство пользователя

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Tem perature
Derating Factors
The continuous current
rating of AKR breakers is
based on their use in an
enclosure in a
40°C
ambient
and on a maximum breaker
temperature of 105°C for
Altitude
Correction Factors
When applying low voltage
power circuit breakers at
altitudes greater than 6600
ft.,
their continuous current
rating must be modified
because a higher tempera­
ture use will be experienced
for a given current rating.
The voltage ratings must
also be modified because of
Standards and Testing
Type AKR low voltage
power circuit breakers are
designed to meet ANSI
standards C37.13 and
C37.16 and are tested to
ANSI C37.50 and C37.14.
The breakers are
UL
listed
and labeled certifying com-
H u m id ity
and Fungus
Ferrous parts are cadmium
or zinc plated for corrosion
protection with the exception
of some parts that are made
from alloy steels and are in­
herently corrosion resistant.
Current-carrying parts are
silver or tin plated for corro-
Class A insulation. Continu­
ous current ratings of AKR
breakers must be derated for
ambient temperatures above
40°C. (If MicroVersaTrip pro­
grammer is used, the
pro­
grammer ambient
is limited
to 70°C.)
the lower dielectric strength.
The short-time and short
circuit current ratings are not
affected by altitude. How­
ever, the short circuit current
rating shall not exceed that
of the voltage class prior to
derating.
Rating correction factor
for low voltage power circuit
breakers are as listed in
ANSI C37.13. 1981 .
pliance with the referenced
ANSI standards.
The test circuit X/R ratio
and power factor required by
ANSI C37.13 for unfused
breakers is 6.6 with 15%
power factor; for fused
breakers is 4.9 with 20%
power factor.
sion protection and to assure
electrical connections.
Tropical treatment is avail­
able and consists of the
application of a fungus
resistant varnish to those
insulating materials that are
not inherently fungus proof.
Derating Factors
Table 29.1 Continuous Current Derating Factors
Ambient Temperature Derating Factor
40°C
1.00
45°C
.95
50°C .89
55°C
.84 (MicroVersaTrip Maximum)
60°C
.77
65°C
.71
70°C .63
Table 29.2 Altitude Correction Factors
Altitude
Rating Correction Factor
Meters Feet
Continuous
Voltage
Current
2000 6600 (and below) 1 .00 1 .00
2600 8500 0.99 0.95
3900 13000 0.96 0.80
Table 29.3 Interrupting Capacity Multiplying
Factors for Power Factor Lower than Test Values
System
System
Multiplying Factor lor
Short Circuit
XIR Ratio
Breaker Short Circuit Rating
Power Factor
Dfo
Unfused LVPCB Fused LVPCB
20 4.9 1 .00 1 .00
15 6.6 1 .00 0.938
12 8.27 0.966
0.902
10 9.95 0.938 0.875
8.5 1 1 .72 0.920
0.847
7 14.25 0.902 0.826
5 20.0 0.875 0.794
29
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