6
Instruction Leaflet
IL29C614F
Effective December 2011
Instructions for The Digitrip RMS 310 3-Pole and
4-Pole Trip Unit Installation and Operation with
K-Frame Series C Circuit Breakers
EATON CORPORATION
www.eaton.com
Finish installation of the 4-pole Trip Unit by following the
instructions in Section 3.5.
3.3 GROUND FAULT TRIP UNIT INSTALLATION
3.3.1 GENERAL
Ground fault trip units are supplied from the factory with
one auxiliary switch with pigtail leads (red, blue and
black wires) and pigtail lead connections for a neutral
current sensor (white and grey wires) and a ground fault
alarm relay (yellow and green wires). A neutral current
sensor is provided with each trip unit, and the ground
fault alarm relay is ordered and shipped separately if
required. If the auxiliary switch or the alarm relay are not
required, the corresponding leads should be cut off
before the trip unit is installed in the breaker.
Digitrip RMS 310 Ground Fault Trip Units detect ground
fault currents through Residual Sensing. They are not
designed to use source ground or zero sequence
ground fault sensing methods. If the system neutral is
grounded, but no phase to neutral loads are used, the
neutral current sensor is not necessary. In that case, the
white and grey leads on the trip unit should be cut off
before installation.
If the system neutral is grounded and phase to neutral
loads are used, then the neutral current sensor (see
Figure
7
) must be used. It should be connected to the
breaker according to the diagram in Figure
8
. It has the
same turns ratio as the phase current sensors in the trip
unit.
The polarity of the sensor connections is critical.
Always observe the polarity markings on the instal-
lation drawings. The polarity markings are identified
as white dots on the transformers. To insure correct
ground fault equipment performance, conduct field
[37,34]
1.47
4X R
[7,11]
.28
4X R
[9,14]
.36
1.50 AT TOP
[38,1]
.03
[0,76]
AT BASE
[73,91]
2.91
.50
12,70]
AT TOP
[144,53]
5.69
[142.49]
5.610
[7,87]
.31
[6,35]
.25
[12,70]
.50
[36.58]
1.44
[30,18]
1.188
AT TOP
[57,15]
2.25
AT BASE
[59,18]
2.33
[29,72]
1.17
AT BASE
[146,05]
5.75
[57,15]
2.25
[55,58]
2.188
2X Ø
[7,11]
THRU HOLE
.280
(
)
([111,13])
4.376
(
)
([50,80])
2.000
(
)
([25,40])
1.000
(
)
([15.67])
.617
T/POTTING
T/CONDUC
TOR
1/2" BOLTS
(NOT INCLUDED)
POLARITY MARKINGS
Figure 7 Neutral Current Sensor.
NOTICE
