Rejection Interlocks; Drawout Circuit Breaker Positioning - Eaton NRX Instruction Manual

Section 3: General operation and circuit breaker description
Figure 14. Step 3.
Keep in mind that all drawout circuit breakers are provided
with safety interlocks to prevent inserting circuit breakers
into incompatible drawout cassettes. Do not force a circuit
breaker that does not roll smoothly into the cassette.
Step 4: To remove the breaker from the cassette lower both
rails down into their extended and locked position. Using
the charging handle pull the breaker out onto the extension
rail.
Figure 15. Step 4.
12
Series NRX with PXR - type RF low voltage power (air) circuit breakers instruction manual MN013002ENH03 September 2016 www.eaton.com

Rejection interlocks

Series NRX drawout circuit breakers come in a variety of
continuous current and interrupting ratings. To prevent the
insertion of a drawout circuit breaker into a cell with which
it is incompatible, rejection interlock key plates are provided
for both the circuit breaker and the cassette. One key plate
is located on the bottom of the circuit breaker and one is
located on the floor of the cassette. Rejection pins must be
installed in both plates to complete the interlock scheme.
The switchboard builder is responsible for installing the
rejection pins in the appropriate pattern in the rejec-
tion plates on both the circuit breaker and cassette. A
rejection pin installation kit, including the instruction leaflet
IL01301006E, is available from Eaton for this purpose.
WARNING
Never attempt to disable any interlocks. Doing so could
result in an electrical fault that could result in death,
bodily injury, and/or equipment damage.

Drawout circuit breaker positioning

Series NRX drawout circuit breakers have four normal posi-
tions:
WITHDRAWN (Figure 16);
●
DISCONNECT (Figure 17);
●
TEST (Figure 18); and
●
CONNECT (Figure 19).
●
The WITHDRAWN position is outside the compartment on
the cassette's drawout rails. The DISCONNECT, TEST, and
CONNECT positions are reached by means of the levering
mechanism and can be achieved with the assembly door
closed.
Figure 16. WITHDRAWN position.
 Breaker in cassette
 Primary connections not made
 Secondary connections not made