Technical data
These ratings are in accordance with the
following standards:
g
ANSI/IEEE C37.04-1999 Standard
Rating Structure for AC High-Voltage
Circuit Breakers
g
ANSI C37.06-2009 AC High-Voltage
Circuit Breakers Rated on a
Symmetrical Current Basis – Preferred
Ratings and Related Required
Capabilities
g
ANSI/IEEE C37.09-1999 Standard Test
Procedure for AC High-Voltage Circuit
Breakers Rated on a Symmetrical
Current Basis
g
ANSI/IEEE C37.010-1999 Application
Guide for AC High-Voltage Circuit
Breakers Rated on a Symmetrical
Current Basis.
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 for which the circuit breaker is
designed, 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.
3,000FC indicates that fan cooling is included in the
switchgear structure for this rating. 3,000 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 - 0.3 s - CO - 3 min. - CO.
7.
Three-cycle (50 ms) interrupting is optionally available.
Technical data
22
Rated values
Circuit breaker type
1
Units 38-3AH3-31 38-3AH3-40
Maximum design voltage (V)
2
kV rms 38.0 38.0
Voltage range factor (K)
3
---- 1.0 1.0
Withstand voltage levels
Power frequency kV rms 80 80
Lightning impulse (BIL) kV crest 150 150
Continuous current
4
A rms
1,200
2,000
3,000FC
1,200
2,000
3,000FC
Short-circuit (I)
5,6
kA rms sym 31.5 40
Interrupting time
7
ms
cycles
83
5
83
5
Permissible tripping delay (Y) Sec 2 2
Maximum symmetrical interrupting (I) kA rms sym 31.5 40
% dc component % 47 47
Short-time current (I) (3 seconds) kA rms 31.5 40
Closing and latching (momentary) asymmetrical (1.55 x I) kA rms 50 62
Closing and latching (momentary) peak (2.6 x I) kA peak 85 104
Table 1: Type 38-3AH3 circuit breaker ratings (new “constant kA” ratings basis)