Instruction manual

Appendix
Measured parameter Units Circuit breaker type
1
38-3AH3-31 38-3AH3-40
General Nominal voltage class kV
38.0 38.0
Rated
values
Rated
voltage
Maximum design voltage (V)
2
kV rms
38.0 38.0
Voltage range factor (K)
3
----
1.0 1.0
Insulation
levels
Withstand
voltage levels
Power-frequency kV rms
80 80
Lightning-impulse (BIL) kV peak
150 150
Rated
current
Continuous
4
A rms
1,200, 2,000,
3,000FC
1,200, 2,000,
3,000FC
Short-circuit (at rated maximum design voltage)
(I)
5, 6
kA rms sym
31.5 40
Interrupting time
7
Cycles/ms
5/83 5/83
Permissible tripping delay (Y) Sec
2 2
Related
required
capabilities
Current Rated maximum design voltage (V) divided by K =
(V/K)
kA rms
38.0 38.0
Maximum symmetrical (sym) interrupting (K x I) kA rms sym
31.5 40
%dc component %
47 47
Short-time current (K x I) (three-seconds) kA rms sym
31.5 40
Closing and
latching
(momentary)
Asymmetrical (1.55 x I) kA rms
49 62
Peak (2.6 x I) kA peak
82 104
Footnotes:
1
"xxxx" in type designation refers to the
continuous current rating 1,200, 2,000 or
3,000 A, as appropriate. The 3,000 A fan-
cooled rating is achieved using fan cooling as
indicated in Footnote 4.
2
Maximum design voltage the circuit breaker is
designed for and the upper limit for operation.
3
K is listed for informational purposes only. For
circuit breakers rated on a "constant kA basis,"
the voltage range factor is 1.0.
4
3000FC indicates fan cooling is included in the
switchgear structure for this rating. 3000 A
rating is not available in outdoor equipment.
5
All values apply to polyphase and line-to-line
faults.
6
Standard duty cycle is O - 0.3s - CO - 3 min. -
CO.
7
Three-cycle (50 ms) interrupting is optionally
available.
These ratings are in accordance with:
ANSI/IEEE C37.04-1999 Standard Rating
Structure for AC High-Voltage Circuit
Breakers
ANSI/IEEE C37.06-2009 AC High-
Voltage Circuit Breakers Rated on a
Symmetrical Current Basis - Preferred
Ratings and Related Required
Capabilities
ANSI/IEEE C37.09-1999 Standard Test
Procedure for AC High-Voltage Circuit
Breakers Rated on a Symmetrical
Current Basis
ANSI/IEEE C37.010-1999 Application
Guide for AC High-Voltage Circuit
Breakers Rated on a Symmetrical
Current Basis.
Table 12: Type 38-3AH3 vacuum circuit breaker ratings (new "constant kA" ratings basis)
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