Effective 7/1/2003
Page 22
I.L. 70C1037H04
Figure 4.5 Short Delay Time Settings
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 8 times
the ampere rating of the installed rating plug (
I
r). For
currents greater than 8 x (
I
r)
the
I
2
t response reverts to the
FLAT response.
NOTE:
Also see Section 3.4, Zone Interlocking.
4.6 Instantaneous Current Setting
There are 8 available Instantaneous Current Settings, as
illustrated in Figure 4.6. Six settings are in the range from
2 to 10 x (
I
n) the rating plug value, and the other two
settings are M1 x (
I
n) or Off. The value that M1 has
depends upon the sensor rating of the circuit breaker and
is specified both on the rating plug label and on the
applicable time-current curves referenced in Section 9.
Figure 4.3 Long Time Memory (LTM) Jumper
The action of the LTM must be considered when performing
multiple Long Delay Time tests
(See Section 5.4).
4.4 Short Delay Current Setting
There are 8 available Short Delay Current Settings, as
illustrated in Figure 4.4. Seven settings are in the range
from 2 to 10 times (
I
r). (
REMEMBER:
(
I
r)
is the Long Delay
Current Setting.
) The maximum value M1 is based on the
ampere rating of the circuit breaker and is listed in Note 4
of Table 1.1.
Figure 4.4 Short Delay Current Settings
4.5 Short Delay Time Setting
As illustrated in Figure 4.5, there are two different Short
Delay response curve shapes: fixed time (FLAT) and I
2
t.
The shape selected depends on the type of selective
coordination chosen. The I
2
t response curve will provide a
longer time delay for current below 8 x
I
r than will the FLAT
response curve.
Connector
(Storage)
“LTM Active
”
Connector
(Bridging)
“LTM Inactive
”
Test
Kit
Test
Kit
(Also Recommended
Position for
Field Testing)
Digitrip Test Kit Port
Notch
Available Settings
2, 2.5, 3, 4, 6, 8, 10, M1
In Multiples of
Long Delay Setting ( r)
I
Short Delay
Setting
M1 Value is Specified on Rating Plug
2 x r
I
