8
Series NRX drawout and breaker
three-way cable interlock installation
and removal instructions
EATON
www.eaton.com
Instructional Leaflet
IL01301070E
Effective June 2016
Section 3: Functional test of interlock
assembly
Type 33
– Six-cable interlock assembly test. Refer to Table 1 for logic
details.
1. CHARGE and CLOSE Breaker A - Breakers B and C should be
held in OPEN condition. Charge Breakers B and C and attempt
to CLOSE them - they should not respond to the CLOSE attempt.
OPEN Breaker A - the interlock should release.
2. CLOSE Breaker B - verify it closes with the OPEN/CLOSED indicator.
Breakers A and C should be held in OPEN condition. Charge
Breakers A and C and attempt to CLOSE them - they should not
respond to the CLOSE attempt. OPEN Breaker B - the interlock
should release.
3. CLOSE Breaker C - verify it closes with the OPEN/CLOSED
indicator. Breakers A and B should be held in OPEN condition.
Charge Breakers A and B and attempt to CLOSE them - they
should not respond to the CLOSE attempt. OPEN Breaker C - the
interlock should release.
Type 31
– Four-cable interlock assembly test. Refer to Table 1 for logic
details.
1. CLOSE Breaker A. Attempt to CLOSE Breaker B - it should not
respond to the CLOSE attempt.
2. CLOSE Breaker C - verify Breaker A remains CLOSED. Again verify
Breaker B will not respond to CLOSE attempt.
3. OPEN Breaker A - verify Breaker B will not respond to CLOSE
attempt.
4. OPEN Breaker C - all breakers are now OPEN. CLOSE Breaker B -
verify Breakers A and C will not respond to CLOSE attempt.
Type 32
– Six-cable interlock assembly test. Refer to Table 2 for logic
details.
1. OPEN all breakers.
2. Charge and CLOSE Breaker A - Breakers B and C should not be
held OPEN - OPEN Breaker A.
3. Charge and CLOSE Breaker B - Breakers A and C should not be
held OPEN - OPEN Breaker B.
4. Charge and CLOSE Breaker C - Breakers A and B should not be
held OPEN - OPEN Breaker C.
5. Charge and CLOSE Breakers A and B - Breaker C should be held
OPEN - OPEN Breakers A and B.
6. Charge and CLOSE Breakers B and C - Breaker A should be held
OPEN - OPEN Breakers B and C.
7. Charge and CLOSE Breaker A and C - Breaker B should be held
OPEN - OPEN Breakers A and C.
The mechanical interlocks are now properly installed with the
successful completion of the appropriate tests. Utilize a light amount
of the supplied lubricant grease (G) if any interlock parts are sticky.
This is only recommended if needed.
Table 1. Types 33 and 31 logic.
A
B
C
A
B
C
Type 33
(six cable)
Type 31
(four cable)
A
B
C
A
B
C
0
0
0
0
0
0
1
0
0
1
0
0
0
1
0
1
0
1
0
0
1
0
0
1
0
1
0
Table 2. Types 32 logic.
Type 32 (six cable)
A
B
C
A
B
C
0
0
0
1
0
0
0
1
0
0
0
1
1
1
0
0
1
1
1
0
1
