GE Industrial Solutions AKD-20 Low Voltage Switchgear - Manuel (Page 19)

AKD-20 Low Voltage Switchgear
Chapter 3. Description
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Each breaker compartment has four positions as described in the following chart:
Breaker Position in
the cassette
Primary
Disconnects
Secondary
Disconnects
Circuit breaker Functionality
Circuit Breaker
door position
CONNECTED Engaged Engaged
• Circuit Breaker can be operated
mechanically or electrically.
• Breaker ready for Service
Closed
TEST Disengaged Engaged
• Circuit Breaker can be operated
mechanically or electrically.
• Breaker and Control circuits
operations can be tested and verified
Closed
DISCONNECTED Disengaged Disengaged
• Circuit Breaker can be operated only
mechanically
• Breaker cannot be removed from the
circuit breaker compartment
Closed
WITHDARWN Disengaged Disengaged
• Circuit Breaker can be operated only
mechanically
• Breaker can be removed from the
circuit breaker compartment
Open
Table 3-1. Description of the breaker positions.
1. Primary disconnects
Fig. 3-10. Frame 2 EntelliGuard G circuit breaker (rear
view)
1. Racking handle
2. Breaker position indicator
Fig. 3-11. Racking handle for movement of EntelliGuard G
Movement of the breaker between the CONNECTED, TEST, and
DISCONNECTED positions is performed by the use of a racking
handle, see Fig 3.11, which engages the racking mechanism
mounted on the cassette. An optional remote racking device is
also available. Movement to the WITHDRAWN position is
manually performed after opening the compartment door.
These positions are illustrated and described more fully in
Chapter 5 of this instruction book.
CAUTION: The door should NOT be opened when the circuit
breaker is closed and in the CONNECTED position. Although
the breaker compartment door may be opened in any
position, it is recommended that the door only be opened
when the breaker is in the DISCONNECTED or WITHDRAWN
position.
ATTENTION: Il ne faut pas que la porte soit ouverte lorsque le
disjoncteur est fermé et branché. Bien que la porte du
compartiment du disjoncteur puisse être ouverte lorsque le
disjoncteur est en n’importe quelle position, il est préférable
que la porte ne soit ouverte que lorsque le disjoncteur est en
position débranchée ou retirée.
3-6 Circuit Breakers
The General Electric EntelliGuard G Low Voltage Power Circuit
Breaker includes spring-operated, stored energy, close and trip
mechanisms for either manual or electrical operation.
Six General Electric EntelliGuard G Circuit Breakers form the
complete family of breakers used in the AKD-20 switchgear.
Each type of breaker listed in table 3.2 describes the breaker
interrupting rating and the letter is the 5
th digit of the breaker
catalog number. These circuit breakers range from 400 to 5000
ampere frame size and are built with the following ratings and
characteristics:
2
1
1