Eaton Cutler-Hammer Digitrip RMS 610, Instruction Leaflet

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17
Instruction Leaflet I. L. 29-886B
Effective August 2011
Instructions for Digitrip RMS 610 Trip Unit
eaton corporation
www.eaton.com
3.7 No Instantaneous Current Setting
For types LS and LSG Trip Units, please see Sections 1 .1 .3
DlScriminator (High initial Current Release) and 1 .1 .4 OVERRIDE
(Fixed Instantaneous), for available fast-acting high short-circuit pro-
tection .
3.8 Ground Fault Current Setting
The eight (8) Ground Fault "Pick-up" Current Settings are labeled
with the code letters "A" through "K" (except there are no "G" or "I"
settings), as illustrated in Figure 17 . In general, the specific current
settings range from 0 .25 to 1 .0 times (I
n
), the rating plug value, but
cannot exceed 1200 A . The specific Ground Current Settings for
each letter are listed in Table 4 and on the (G) Time-Current Curve
applicable for the circuit breaker (see Section 5) .
otee: N For Testing Purposes Only: When using an external single phase current
source to test low level ground fault current settings, it is advisable to use the
Auxiliary Power Module (APM) (see Section 1 .5 and Figure 11) .
Figure 17. Ground Fault Current Settings.
Table 4. Ground Fault Current Settings.
Ground Fault current Settings
(amperes)

installed
r
ating
p
lug
(a
mperes)
i
n

a B c D e F H K
100 25 30 35 40 50 60 75 100
200 50 60 70 80 100 120 150 200
250 63 75 88 100 125 150 188 250
300 75 90 105 120 150 180 225 300
400 100 120 140 160 200 240 300 400
600 150 180 210 240 300 360 450 600
630 158 189 221 252 315 378 473 630
800 200 240 280 320 400 480 600 800
1000 250 300 350 400 500 600 750 1000
1200 300 360 420 480 600 720 900 1200
1250 312 375 438 500 625 750 938 1200
1600 400 480 560 640 800 960 1200 1200
2000 500 600 700 800 1000 1200 1200 1200
2400 600 720 840 960 1200 1200 1200 1200
2500 625 750 875 1000 1200 1200 1200 1200
3000/3150 750 900 1050 1200 1200 1200 1200 1200
3200 800 960 1120 1200 1200 1200 1200 1200
4000 1000 1200 1200 1200 1200 1200 1200 1200
5000 1200 1200 1200 1200 1200 1200 1200 1200

Tolerances on settings are ± 10% of values shown.

Refer to Type DS, Type SPB, or Series C R-Frame supplemental instruction leaflets
given in Section 5 for list of available rating plugs for each type circuit breaker.
Available Settings
A.
Specific Values
Given on Circuit
Breaker time-Current
Curve and in Table 1
3.9 Ground Fault Time Delay Setting
As illustrated in Figure 18, there are two different Ground Fault
curve shapes, i .e ., fixed time (flat) and I
2
t response . The shape
selected depends on the type of selective coordination chosen . The
I
2
t response will provide a longer time delay in the low-end of the
ground fault current range than will the flat response .
Five flat ( .1, .2, .3, .4, .5 sec .) and three I
2
t ( .1*, .3*, .5* sec .)
response time delay settings are available . The I
2
t response settings
are identified by the suffix asterisk (*) that appears in the setting
viewing window . The I
2
t response is applicable to currents less than
0 .625 x I
n
, (the I
n
value is marked on the installed rating plug) . For
currents greater than 0 .625 x I
n
, the I
2
t response reverts to the flat
response .
otee: N See also Section 1 .1 .5 on Zone Interlocking .
otee: N
In addition to the standard Ground Fault protection, the Digitrip RMS
610 Trip Unit also has a GROUND TIME MEMORY (GTM) function, which
serves to protect loads in the event of a sputtering arc to ground . Without
the GTM function, the Trip Unit would normally reset each time the arc sput-
tered, and begin to time-out all over again, so that a sputtering fault may not
have been detected . But with the GTM function, the Trip Unit "remembers"
the sputtering ground current for up to five (5) times the Ground Fault Time
Setting . After that time, it does reset automatically . The GTM function does
reset rather quickly; on the 0 .1 second setting, for example, it will reset in
0 .5 second .
Figure 18. Ground Fault Time Delay Settings.
.1*, .3*, .5*
.1, .2, .3, .4, .5
I
Available Settings
- -------
I I
.
Seconds with
Flat Response
,
.
.
Shape
Returns to Flat
Responses at
Approximately
0.625
Seconds With
“*” In Shape
Indicates
Shape
.3 Sec.
Gnd. Fault
Time
I
n
I t
2
I t
2
I t
2
Viewing Window