beautypg.com

Appendix – Siemens vacuum circuit breaker 38-3AH3 38 kV User Manual

Page 64

background image

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)

64