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Effective 8/13/99
Page 21
I.L. 70C1037H02
M 1 va lu e is sp e cifie d on ra tin g plu g.
*N o O FF on D igitrip 2 20 .
S ettin g In st.
x n
I
6
Available S etting s
2, 3, 4 , 6, 8,
10, M 1, O FF *
In M u ltiples of
R ating P lug
A m p eres ( n)
I
Figure 4.6 Instantaneous Current Settings
4.7 Ground Fault Current Setting
The 8 Ground Fault Current Settings are labeled with
values from .25 to 1.0 x (
In) (see Figure 4.7). The domes-
tic (U.S.) models have a maximum of 1200A, limited by
the firmware of the unit, as shown in Table 1.1 and Table
2.2. The specific Ground Current Settings for each model
are listed in Table 2.2 and on the applicable time-current
curve for the breaker.
Available S ettin gs
0.25, .3, .35, .4,
.5, .6, .7 5, 1.0
S pecific Values
G iven o n C ircuit
B reaker Tim e -C urrent
C urve and in Table 2.2
G n d-Fau lt
S ettin g
x n
I
.4
Figure 4.7 Ground Fault Current Settings
4.8 Ground Fault Time Delay Setting
As illustrated in Figure 4.8, there are two different Ground
Fault curve shapes: fixed time (FLAT) or I
2
t response. The
shape selected depends on the type of selective coordi-
nation chosen. The I
2
t response will provide a longer time
delay for current below 0.625 x
In than will the FLAT
response.
Five FLAT (.1, .2, .3, .4, .5 seconds) and three I
2
t (.1*, .3*,
.5* seconds) response time delay settings are available.
The I
2
t response settings are identified by an asterisk (*).
The I
2
t response is applicable to currents less than 0.625
times the ampere rating of the installed rating plug (
In).
For currents greater than 0.625 x (
In)
the
I
2
t response
reverts to the FLAT response.
NOTE: Also see Section 3.4, Zone Interlocking.
Figure 4.8 Ground Fault Time Delay Settings
5.0 TEST PROCEDURES
5.1 General
WARNING
DO NOT ATTEMPT TO INSTALL, TEST, OR PERFORM
MAINTENANCE ON EQUIPMENT WHILE IT IS ENER-
GIZED. DEATH OR SEVERE PERSONAL INJURY CAN
RESULT FROM CONTACT WITH ENERGIZED EQUIP-
MENT.
DE-ENERGIZE THE CIRCUIT AND DISCONNECT THE
CIRCUIT BREAKER BEFORE PERFORMING MAINTE-
NANCE OR TESTS.
WARNING
ANY TRIPPING OPERATION WILL CAUSE DISRUP-
TION OF SERVICE AND POSSIBLE PERSONAL
INJURY, RESULTING IN THE UNNECESSARY
SWITCHING OF CONNECTED EQUIPMENT.