Eaton NRX Serie Montageanweisung Seite 2

Instruction Leaflet IL01301046E
effective September 2013
Section 1: Neutral Current Sensor Installation
Ground Fault Trip Units detect ground fault currents through Residual
Sensing. A different, round, torroidal sensor is required for source
ground or zero sequence sensing. All further information is for residual
ground fault sensing method only. If the system neutral is grounded
and residual ground fault is desired, but no phase to neutral loads
are used, a neutral current sensor is not necessary. In that case,
no additional connections are required to circuit breaker secondary
contacts.
If the system neutral is grounded and phase to neutral loads are
used, then the neutral current sensor (see Figure 3) must be used to
account for this load in the residual ground fault sensing. It has the
same turns ratio as the phase current sensors in the Series NRX circuit
breaker. The neutral sensor is an air core design and can be used with
all Type RF rating plugs (Figure 1). See Figure 2 for installation details.
• IMPORTANT
THE POLARITY OF THE SENSOR CONNECTIONS IS CRITICAL. ALWAYS
OBSERVE THE POLARITY MARKINGS ON THE INSTALLATION DRAWINGS.
THE POLARITY MARKINGS ARE IDENTIFIED AS WHITE DOTS ON THE
TRANSFORMERS. TO INSURE CORRECT GROUND FAULT EQUIPMENT
PERFORMANCE, CONDUCT FIELD TESTS TO COMPLY WITH NATIONAL
ELECTRIC CODE REQUIREMENTS UNDER ARTICLE 230-95-C. SEE
PERFORMANCE TESTING INSTRUCTIONS ON FOLLOWING PAGES.
Figure 1. Dimensions.
2 EATON www.eaton.com
WHITE POLARITY
LEAD WIRE
.250
1.574
[39,98]
.144
[3,64]
.500
[12,7]
3.594
[91,29]
1.060
[26,92]
.530
[13,46]
(.787 )
[19,99]
All dimensions in inch (mm).
Instructions for Series NRX Neutral
Section 2: Performance Testing For Ground
Fault Circuit Breakers
General Test Instructions
The interconnect system shall be evaluated in accordance with the
equipment assembler's detailed instruction by qualified personnel.
The polarity of the neutral sensor connection (if used) must agree
with equipment assembler's detailed instructions to avoid improper
operations following apparently correct simulated test operations.
Where a question exists, consult the specifying engineer and/or
equipment assembler.
The grounding points of the system shall be verified to determine that
ground paths do not exist that would bypass the sensors. High-voltage
testers and resistance bridges may be used.
.938
[23,83]
1.50
[38,1]
(3.937)
[100]
(1.063) (1.574 )
[27] [39,98]
(2.637 )
[66,98]
(3.700 )
[93,98]
Current Sensor – Type RF
1.002
[25,44]
8X ( .463 -.417)
(11.76-10.6)
3X (.984)
[24,99]
.49
[12,5]