Eaton Digitrip RMS 910 User manual

Cutler
-
Hammer
I
.
L
.
29
-
889
A
Instructions
for
Digitrip
RMS
910
Trip
Unit
Table
of
Contents
Page
Information
Communicated
by
Digitrip
RMS
910
.
..
27
Waveform
Capture
Remote
CLOSing
and
TRIPping
of
Breakers
Remote
Resetting
of
the
Trip
Unit
References
Digitrip
RMS
Trip
Assemblies
Type
DS
Low
-
Voltage
AC
Power
Circuit
Breakers
.
.
28
Type
SPB
Systems
Pow
-
R
Series
C
®
R
-
Frame
Molded
Case
Ckt
.
Breakers
.
.
.
29
Assemblies
Electronic
Monitors
INCOM
®
and
IMPACC
®
Communications
Lists
of
Figures
,
Tables
,
and
Appendices
5.6
5.7
27
1.0
General
Description
-
RMS
910
Trip
Unit
System
.
.
.
2
1.1
Basic
RMS
910
Trip
Unit
1.1
.
1
Operational
Status
and
TRIP
Indicators
1.1
.
2
General
Over
-
Current
Protection
1.1
.
3
Discriminator
(
Making
Current
Release
)
1.1
.
4
OverRIDe
(
Fixed
Instantaneous
)
TRIP
1.1
.
5
Zone
Interlocking
1.2
Four
-
Character
Information
Display
Window
..
.
1.2
.
1
Values
Displayed
During
Normal
Service
1.2
.
1.1
Instrumentation
-
Current
Values
1.2
.
1.2
Instrumentation
-
Voltage
Values
1.2
.
1.3
Instrumentation
-
Power
,
Power
Factor
and
Energy
Values
1.2
.
1.4
Harmonics
[
THD
]
1.2
.
2
Messages
Displayed
After
ALARM
or
TRIP
.
..
.
1.2
.
2.1
ROM
Error
See
I
.
L
1.3
Frame
Rating
,
Sensor
Rating
(
where
applicable
)
and
Rating
Plugs
1.4
Power
/
Relay
Module
1.5
Potential
Transformer
Module
1.6
Auxiliary
Power
Module
2.0
UL
Listed
Devices
3.0
Protection
Settings
3.1
General
3.2
Long
Delay
Current
Setting
3.3
Long
Delay
Time
Setting
3.4
Short
Delay
Current
Setting
3.5
Short
Delay
Time
Setting
3.6
Instantaneous
Current
Setting
3.7
NO
Instantaneous
Current
Setting
3.8
Ground
Fault
Current
Setting
3.9
Ground
Fault
Time
Delay
Setting
4.0
Test
Procedures
4.1
General
4.2
When
to
Test
4.3
Testing
Provisions
4.4
Conducting
Tests
4.4
.
1
Not
Tripping
the
Breaker
4.4
.
2
Tripping
the
Breaker
4.5
Testing
the
Back
-
up
Battery
-
Inside
the
Rating
Plug
22
4.5
.
1
Back
-
up
Battery
Check
4.5
.
2
Replacing
the
Back
-
up
Battery
5.0
Communications
5.1
Trip
Unit
Address
and
Baud
Rate
5.2
Remote
Master
Computer
5.3
Assemblies
Electronic
Monitor
(
AEM
)
.
.
5.4
Both
Remote
Master
Computer
and
AEM
5.5
INCOM
®
Network
Interconnections
5.8
27
2
5.9
28
2
6.0
28
4
6.1
28
4
6.2
7
6.3
29
7
6.4
7
6.5
29
7
6.6
29
8
29
8
9
WARNING
11
12
13
DO
NOT
ATTEMPT
TO
INSTALL
OR
PERFORM
MAIN
-
TENANCE
ON
EQUIPMENT
WHILE
IT
IS
ENERGIZED
.
DEATH
OR
SEVERE
PERSONAL
INJURY
CAN
RESULT
FROM
CONTACT
WITH
ENERGIZED
EQUIP
-
MENT
.
ALWAYS
VERIFY
THAT
NO
VOLTAGE
IS
PRESENT
BEFORE
PROCEEDING
WITH
THE
TASK
,
AND
ALWAYS
FOLLOW
GENERALLY
ACCEPTED
SAFETY
PROCEDURES
.
CUTLER
-
HAMMER
INC
.
IS
NOT
LIABLE
FOR
THE
MISAPPLICATION
OR
MISIN
-
STALLATION
OF
ITS
PRODUCTS
.
13
14
15
16
16
17
17
17
17
18
It
is
strongly
urged
that
the
user
observe
all
recommen
-
dations
,
warnings
and
cautions
relating
to
the
safety
of
personnel
and
equipment
,
as
well
as
all
general
and
local
health
and
safety
laws
,
codes
,
and
procedures
.
The
recommendations
and
information
contained
herein
are
based
on
experience
and
judgment
,
but
should
not
be
considered
to
be
all
-
inclusive
or
covering
every
appli
-
cation
or
circumstance
which
may
arise
.
If
you
have
any
questions
or
need
further
information
or
instructions
,
please
contact
your
local
representative
,
or
the
Customer
Support
Center
for
the
type
of
circuit
breaker
you
have
.
Send
to
Telephone
FAX
Number
Number
-
(
442
)
^
037
6020
-
-
-
(
4
t
2
y
937
-
6396
(
44
2
)
037
-
6029
-
'
'
-
(
412
)
937
-
6396
-
(
44
-
2
^
93
^
6490
-
.
~
-
18
18
18
18
18
19
19
19
20
20
21
21
Circuit
Breaker
Type
DS
/
DSL
SPB
Series
C
R
-
Frame
Call
22
22
22
23
26
26
(
412
)
937
-
6010
27
27
E
:
T
'
N
Effective
May
1997
Courtesy of store.ips.us

I
.
L
.
29
-
889
A
Page
2
1.0
GENERAL
DESCRIPTION
-
DIGITRIP
RMS
910
TRIP
UNIT
carrying
current
.
These
signals
develop
analog
voltages
across
the
appropriate
sensing
resistors
including
:
1
)
Phase
currents
2
)
Ground
current
or
Neutral
current
(
when
supplied
)
3
)
Rating
plug
4
)
Phase
Voltages
The
resulting
analog
voltages
are
digitized
by
the
custom
designed
integrated
circuits
.
The
micro
-
computer
,
in
cyclic
fashion
,
repeatedly
scans
the
voltage
values
across
each
sensing
resistor
and
enters
these
values
into
its
Random
Access
Memory
(
RAM
)
.
These
data
are
used
to
calculate
true
RMS
current
values
,
which
are
then
repeatedly
compared
with
the
protection
function
settings
and
other
operating
data
stored
in
the
memory
.
The
soft
-
ware
program
then
determines
whether
to
initiate
protec
-
tion
functions
,
including
tripping
the
breaker
through
the
low
energy
trip
device
(
Flux
Transfer
Shunt
Trip
or
Direct
Trip
Actuator
)
in
the
circuit
breaker
.
1.1
Basic
Digitrip
RMS
910
Trip
Unit
The
Digitrip
RMS
910
,
illustrated
in
Fig
.
1
,
is
a
Trip
Unit
,
suitable
for
use
in
types
DS
and
DSL
Low
-
Voltage
AC
power
circuit
breakers
and
type
SPB
Systems
Pow
-
R
cir
-
cuit
breakers
and
Series
C
R
-
Frame
molded
case
circuit
breakers
.
The
Digitrip
RMS
910
Trip
Unit
provides
five
basic
functions
:
Function
Protection
Information
Monitors
:
Current
Voltage
Power
,
Power
Factor
and
Energy
Harmonics
and
[
THD
]
Testing
Communications
Remote
CLOSE
/
OPEN
Control
5.8
Digitrip
RMS
910
provides
true
RMS
current
sensing
for
proper
correlation
with
thermal
characteristics
of
conduc
-
tors
and
equipment
.
Interchangeable
rating
plugs
are
provided
to
establish
the
continuous
current
rating
of
each
circuit
breaker
.
The
Digitrip
RMS
910
Trip
Unit
is
designed
for
use
in
industrial
circuit
breaker
environ
-
ments
where
the
ambient
temperatures
can
range
from
-
20
C
to
+
85
C
and
rarely
exceed
70
to
75
C
.
If
,
however
,
temperatures
in
the
neighborhood
of
the
Trip
Unit
do
exceed
this
range
,
the
Trip
Unit
performance
may
be
degraded
.
In
order
to
insure
that
the
tripping
function
is
not
compromised
due
to
an
over
-
temperature
condition
,
the
Digitrip
RMS
910
microcomputer
chip
has
a
built
-
in
over
-
temperature
protection
feature
,
factory
set
to
trip
the
breaker
if
the
chip
temperature
exceeds
95
C
.
If
over
-
temperature
is
the
reason
for
the
trip
,
the
Long
Delay
Time
LED
will
light
“
RED
"
,
and
the
word
“
TEMP
”
will
appear
in
the
display
window
.
The
Trip
Unit
employs
the
Cutler
-
Hammer
Inc
.
custom
designed
integrated
circuit
SpRE
+
chip
,
which
includes
a
micro
-
computer
to
perform
its
numeric
and
logic
functions
.
The
principle
of
operation
is
described
by
the
block
diagram
shown
in
Fig
.
2
.
In
the
Digitrip
RMS
910
Trip
Unit
,
all
required
sensing
and
tripping
power
to
operate
its
protection
function
is
derived
from
the
current
sensors
in
the
circuit
breaker
.
The
secondary
currents
from
these
sensors
provide
the
correct
input
information
for
the
protector
functions
,
as
well
as
tripping
power
,
whenever
the
circuit
breaker
is
Section
1.1
.
2
-
1.1
.
5
and
3
1.1
.
1
and
1.2
1.2
.
1
1.2
.
1.1
1.2
.
1.2
1.2
.
1.3
1.2
.
1.4
and
5.7
4
1.4
and
5
1.1
.
1
Operational
Status
and
Protection
TRIP
Indicators
The
“
Green
”
Light
Emitting
Diode
(
LED
)
in
the
lower
right
corner
of
the
Trip
Unit
(
Fig
.
1
)
“
blinks
”
once
each
second
to
indicate
the
Trip
Unit
is
operating
normally
.
Note
:
If
the
LED
is
steadily
“
GREEN
”
,
i
.
e
.
not
blink
-
ing
,
the
Trip
Unit
is
not
ready
.
Check
the
120
VAC
control
power
to
the
Power
/
Relay
Module
,
if
the
LED
is
not
blinking
.
(
See
Section
1.4
.
)
The
LEDs
,
shown
in
Figs
.
1
and
3.1
thru
3.6
on
the
face
of
the
Trip
Unit
,
light
“
RED
”
to
indicate
the
reason
for
any
automatic
trip
operation
.
As
indicated
in
Figs
.
3.1
-
3.6
,
each
LED
is
strategically
located
in
the
related
segment
of
the
time
-
current
curve
depicted
on
the
face
of
the
Trip
Unit
.
The
reason
for
trip
is
identified
by
the
segment
of
the
time
-
current
curve
where
the
LED
is
lighted
“
RED
”
,
is
also
identified
on
the
Display
.
Following
an
automatic
pro
-
tection
trip
operation
,
the
external
control
power
to
the
Power
/
Relay
Module
(
see
Section
1.4
)
will
maintain
the
LED
“
RED
”
and
will
continue
to
send
a
TRIP
signal
to
LOCKOUT
the
circuit
breaker
until
the
Trip
Unit
is
RESET
.
The
Digitrip
RMS
910
Trip
Unit
can
be
RESET
in
two
ways
:
•
either
press
and
release
the
“
TRIP
RESET
”
button
(
See
Fig
.
1
lower
right
corner
just
above
the
“
UNIT
STATUS
”
LED
.
)
,
or
•
by
the
“
Trip
Reset
”
remote
communications
function
.
(
See
Section
5.9
.
)
E
^
T
*
N
Effective
May
1997
Courtesy of store.ips.us

I
.
L
.
29
-
889
A
Page
3
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Fig
.
2
RMS
Digitrip
910
Trip
Unit
-
Block
Diagram
FiT
-
N
Effective
May
1997
Courtesy of store.ips.us

I
.
L
.
29
-
889
A
Page
4
In
the
event
that
control
power
is
lost
,
the
back
-
up
battery
in
the
Rating
Plug
(
see
Section
1.3
and
Figs
.
1
and
4
)
continues
to
supply
power
to
the
LEDs
.
To
check
the
sta
-
tus
of
the
battery
,
see
Section
4.5
.
Note
:
The
Digitrip
RMS
910
performs
all
of
its
protec
-
tion
functions
regardless
of
the
status
of
the
battery
.
The
battery
serves
only
to
maintain
the
indication
of
the
reason
for
automatic
trip
.
Press
and
release
the
“
TRIP
RESET
”
push
-
button
shown
in
Fig
.
1
,
to
turn
“
Off
”
the
LEDs
following
a
trip
operation
.
TROL
POWER
REMAINS
AVAILABLE
TO
THE
POWER
/
RELAY
MODULE
.
THE
TRIP
UNIT
MUST
BE
RESET
.
BEFORE
THE
CIRCUIT
BREAKER
CAN
BE
CLOSED
AGAIN
.
THE
RESET
CAN
BE
ACCOM
-
PLISHED
EITHER
LOCALLY
BY
PRESSING
AND
RELEASING
THE
"
TRIPRESET
’
PUSH
BUTTON
(
SEE
FIG
.
1
)
,
OR
REMOTELY
BY
THE
IMPACC
SYSTEM
.
(
SEE
SECTION
5.9
.
)
After
an
over
-
current
trip
operation
,
the
following
informa
-
tion
is
stored
in
the
Trip
Unit
memory
:
•
the
cause
of
trip
,
•
the
values
of
currents
at
time
of
trip
,
•
the
time
when
the
trip
operation
occurred
,
•
the
total
number
of
times
the
Trip
Unit
has
tripped
the
breaker
electronically
,
(
does
not
count
shunt
trip
or
manual
operations
)
If
the
120
VAC
control
power
remains
available
to
the
Power
/
Relay
Module
,
this
information
can
be
viewed
by
INCOM
®
/
IMPACC
®
.
(
See
Section
5.6
.
)
Therefore
,
users
may
want
to
use
an
uninterruptable
power
supply
for
the
control
power
to
the
power
relay
module
.
1.1
.
2
General
Over
-
Current
Protection
The
Digitrip
RMS
910
Trip
Unit
is
completely
self
-
con
-
tained
and
when
the
circuit
breaker
is
closed
,
requires
no
external
control
power
to
operate
its
protection
sys
-
tems
.
It
operates
from
current
signal
levels
and
control
power
derived
through
current
sensors
integrally
mounted
in
the
circuit breaker
.
The
Digitrip
RMS
910
Trip
Unit
is
available
in
six
different
types
.
Each
Trip
Unit
may
be
equipped
with
a
maximum
of
five
phase
and
two
ground
(
time
-
current
)
settings
(
see
Section
3
)
to
meet
specific
application
requirements
.
The
protection
available
for
each
type
is
summarized
in
Table
1
,
and
illustrated
in
Figures
3.1
through
3.6
:
Protection
Functions
Long
Time
/
Instantaneous
Long
Time
/
Short
Time
Long
Time
/
Short
Time
/
Instantaneous
LSI
*
3.3
Long
Time
/
Instantaneous
/
Ground
Long
Time
/
Short
Time
/
Ground
Long
Time
/
Short
Time
/
Instantaneous
/
Ground
NOTE
*
:
RMS
Digitrip
Type
LI
,
LS
and
LSI
Trip
Units
can
be
applied
on
3
-
pole
or
4
-
pole
circuit
breakers
for
protection
of
the
neutral
circuit
,
IF
the
circuit
breaker
is
wired
and
MARKED
for
NEUTRAL
PROTECTION
.
Refer
to
the
National
Electric
Code
for
appropriate
application
of
4
-
pole
breakers
.
1.1
.
3
Discriminator
(
High
Initial
Current
Release
)
(
For
Types
LS
and
LSG
Trip
Units
only
)
When
the
Digitrip
RMS
910
Trip
Unit
is
not
equipped
with
an
adjustable
instantaneous
protection
setting
,
i
.
e
.
types
LS
or
LSG
,
a
Discriminator
circuit
(
or
high
initial
current
release
)
is
provided
.
The
non
-
adjustable
release
is
pre
-
set
at
eleven
(
11
)
times
the
installed
rating
plug
cur
-
rent
(
ln
)
.
The
Discriminator
is
enabled
for
approximately
ten
(
10
)
cycles
following
the
initial
current
flow
through
the
circuit
breaker
,
provided
the
load
current
exceeds
approximately
10
%
of
the
circuit
breaker
frame
(
or
cur
-
rent
sensor
)
rating
.
Whenever
the
load
current
falls
below
10
%
the
discriminator
is
rearmed
.
The
release
,
once
rearmed
will
remain
enabled
until
the
load
current
pass
-
ing
through
the
circuit
breaker
has
exceeded
the
10
%
value
for
10
cycles
.
Whenever
the
Discriminator
trips
the
circuit
breaker
,
the
“
OVERRIDE
/
DIS
”
LED
will
light
“
RED
”
,
and
the
Display
will
read
“
DISC
”
.
In
the
event
the
breaker
is
not
intended
to
trip
out
on
a
circuit
whose
current
could
initially
be
higher
than
1 1
x
1
it
is
possible
to
make
the
Discriminator
inactive
.
Type
Figure
LI
*
3.1
LS
*
3.2
LIG
3.4
LSG
3.5
LSIG
3.6
NOTICE
AFTER
EACH
TRIP
OPERATION
(
WHETHER
DUE
TO
OVERCURRENT
PROTECTION
OR
REMOTE
CON
-
TROL
)
THE
AUTOMATIC
LOC
/
COU
7
-
AFTER
-
TRIP
FEATURE
OF
THE
DIGITRIP
RMS
910
TRIP
UNIT
MAINTAINS
THE
CIRCUIT
BREAKER
IN
A
“
TRIP
-
FREE
”
CONDITION
,
PROVIDED
120
VAC
CON
-
rv
F
:
T
"
N
Effective
May
1997
Courtesy of store.ips.us

11.29
-
889
A
Page
5
TABLE
1
-
DIGITRIP
RMS
910
PROTECTION
FUNCTIONS
RMS
DIGITRIP
910
Trip
Unit
TYPE
S
SS
999
2
3
3
3
3
L
L
L
I
S
S
s
s
s
9
9
9
5
6
3
3
3
L
L
L
S
S
4
1
Refer
to
I
.
L
.
Section
Number
Catalog
Number
I
GG
G
Suffix
Number
91
92
93
94
95
96
Instruction
Leaflet
No
.
I
.
L
.
29
-
889
Long
-
Time
Delay
Protection
Adj
.
Current
Setting
(
Pick
-
up
)
Adj
.
Time
Delay
Setting
Long
Time
Memory
XXX
XXX
XXX
XXX
XXX
XXX
3.2
3.3
3.3
High
Load
Alarm
ALARM
Indication
a t
Trip
Unit
Remote
ALARM
Signal
Contacts
Table
3
XXX
XXX
XXX
XXX
1.3
Short
-
Time
Delay
Protection
Ad
|
.
Current
Setting
(
Pick
-
up
)
Adj
Time
Delay
Setting
Opt
"
I
squared
T
'
Curve
Shape
Opt
.
Zone
Interlocking
XX
XX
XX
XX
X
X
X
X
X
X
X
X
3.4
3.5
3.5
1.1
.
5
Instantaneous
Protection
Adj
.
Current
Setting
(
Pick
-
up
)
DISCnminator
(
11
x
)
IN
or
OUT
OverRIDe
(
>
short
time
current
rating
)
XX
X
X
3.6
XX
1.1
.
3
1.1
.
4
1
1
1
1
1
1
Neutral
Current
Protection
1.1
.
1
n
n
n
Ground
Fault
Protection
Adj
Current
Setting
(
Pick
-
up
)
Adj
.
Time
Delay
Setting
Opt
"
I
squared
T
Curve
Shape
Opt
.
Zone
Interlocking
Ground
Fault
Time
Memory
XXX
XXX
XXX
XXX
XXX
3.8
3.9
3.9
1.1
.
5
3.9
XXX
Trip
Unit
Over
-
Temp
.
TRIP
XXX
1.1
Auto
Lock
-
Out
after
TRIP
1.1
.
2
c
.
r
c
,
r
c
.
r
c
,
r
c
,
r
c
,
r
LED
Indicators
on
TRIP
Unit
:
Trip
Unit
Status
(
OK
=
Blinking
)
Long
-
Time
Delay
TRIP
Short
-
Time
Delay
TRIP
XXX
XXX
X
X
XXX
XXX
X
X
1.1
.
2
1.1
.
2
1.1
.
2
X
1.1
.
2
1.1
.
2
1.1
.
2
INStantaneous
TRIP
OverRIDe
/
DISCriminator
TRIP
Ground
Fault
TRIP
X
X
X
XX
XXX
XXX
4.5
Rating
Plug
Back
-
up
Battery
Status
XXX
XXX
4
Integral
Test
Provision
XXX
POWER
/
RELAY
MODULE
Output
Signal
Contacts
:
XXX
XXX
1.4
XXX
XXX
Long
-
Time
Delay
TRIP
1.4
XXX
Short
-
Circuit
TRIP
(
includes
any
of
:
)
•
Short
-
Time
Delay
TRIP
•
INStantaneous
TRIP
•
OverRIDe
/
DISCriminator
TRIP
XXX
1.4
XXX
1.4
Ground
Fault
TRIP
Neutral
Current
ALARM
High
LoaD
ALARM
XXX
XXX
1.4
XXX
1.4
LEGEND
:
x
=
Function
included
for
this
trip
unit
c
=
120
VAC
Control
Power
required
to
maintain
Lockout
n
=
Circuit
Breaker
must
be
equipped
for
Neutral
Protection
r
=
Trip
Unit
can
be
re
-
set
Remotely
via
INCOM
/
IMPACC
*
=
“
DISCriminator
”
is
also
called
“
Making
Current
Release
”
1
=
n
/
a
for
Type
DS
Breakers
“
blank
"
=
Function
n
/
a
for
this
trip
unit
Fig
.
3.2
Digitrip
RMS
910
Type
LS
F
;
T
*
N
Effective
May
1997
Courtesy of store.ips.us

I
.
L
.
29
-
889
A
Page
6
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ins
*
Fig
.
3.5
Digitrip
RMS
910
Type
LSG
Fig
.
3.3
Digitrip
RMS
910
Type
LSI
Fig
.
3.6
Digitrip
RMS
910
Type
LSIG
Fig
.
3.4
Digitrip
RMS
910
Type
LIG
F
:
T
>
N
Effective
May
1997
Courtesy of store.ips.us

I
.
L
.
29
-
889
A
Page
7
This
signal
requires
that
only
a
single
pair
of
wires
be
connected
from
the
interlock
output
terminals
of
the
downstream
breaker
’
s
Trip
Unit
,
to
the
interlock
input
ter
-
minals
of
the
upstream
breaker
’
s
Trip
Unit
.
For
specific
instructions
see
the
applicable
connection
diagrams
for
your
breaker
listed
in
Section
6
.
Note
:
If
a
breaker
(
M
)
receives
a
Zone
Interlocking
signal
from
another
breaker
(
F
)
that
is
tripping
,
but
the
fault
current
level
is
less
than
the
setting
for
breaker
(
M
)
,
the
presence
of
the
Zone
Interlocking
signal
from
the
other
breaker
(
F
)
can
not
cause
breaker
(
M
)
to
trip
.
If
a
circuit
breaker
would
close
onto
a
high
short
-
circuit
current
,
when
the
Discriminator
is
inactive
,
type
LS
or
LSG
Trip
Units
will
rely
on
the
short
-
time
delay
function
before
tripping
.
If
the
fault
current
exceeds
the
short
-
time
withstand
current
capability
of
the
circuit
breaker
,
the
OverRIDe
protection
function
will
trip
the
breaker
without
delay
.
(
See
Section
1.1
.
4
.
)
Also
,
please
see
Section
1.1
.
5
for
other
exceptions
when
Zone
Interlocking
is
employed
.
The
Discriminator
(
high
initial
current
release
)
can
be
made
inactive
by
turning
the
“
OVERRIDE
/
”
setting
switch
(
nearest
the
bottom
edge
of
the
Trip
Unit
)
from
the
“
DIS
”
position
,
to
the
“
[
blank
]
”
position
.
(
See
Figs
.
3.2
and
3.5
)
Notes
:
This
switch
has
eight
(
8
)
positions
,
and
seven
(
7
)
of
the
positions
show
“
DIS
”
in
the
window
,
ONLY
ONE
position
shows
“
[
blank
]
”
.
When
the
“
OVERRIDE
/
”
window
shows
“
[
blank
]
”
,
the
only
fast
-
acting
high
short
-
circuit
protection
avail
-
able
is
the
OVERRIDE
(
Fixed
Instantaneous
)
.
(
See
Section
1.1
.
4
.
)
1.1
.
4
OVERRIDE
(
Fixed
Instantaneous
)
Each
Digitrip
RMS
910
Trip
Unit
has
a
Fixed
Instanta
-
neous
“
Override
"
analog
trip
circuit
pre
-
set
to
a
value
no
greater
than
the
short
-
time
withstand
current
rating
of
the
circuit
breaker
in
which
the
Trip
Unit
is
installed
.
Since
the
specific
values
vary
for
different
circuit
breaker
types
and
ratings
,
refer
to
time
-
current
curves
,
listed
in
Section
6
,
for
the
values
applicable
to
your
breaker
.
If
breaker
trips
due
to
high
instantaneous
current
,
the
“
OVERRIDE
/
”
LED
will
light
“
RED
”
,
and
the
display
will
read
“
ORID
”
.
CAUTION
IF
ZONE
INTERLOCKING
IS
NOT
TO
BE
USED
(
I
.
E
.
STANDARD
TIME
-
DELAY
COORDINATION
ONLY
IS
INTENDED
)
,
THE
ZONE
INTERLOCKING
TERMINALS
MUST
BE
CONNECTED
WITH
JUMPER
WIRES
,
AS
SPECIFIED
ON
THE
CONNECTION
DIAGRAMS
FOR
YOUR
BREAKER
(
SEE
SECTION
6
)
,
SO
THE
TIME
-
DELAY
SETTINGS
WILL
PROVIDE
THE
INTENDED
COORDINATION
.
For
examples
of
how
Zone
Selective
Interlocking
may
be
used
,
See
Appendix
A
.
1.2
Four
Character
Information
Display
Window
The
four
-
digit
alpha
-
numeric
display
window
,
illustrated
in
Figs
.
1
and
2
,
serves
two
basic
purposes
:
instrumenta
-
tion
and
mode
of
trip
and
trouble
indication
.
The
informa
-
tion
displayed
in
the
window
is
listed
in
Tables
2
and
3
.
1.2
.
1
Values
Displayed
During
Normal
Service
The
alpha
-
numeric
display
window
provides
informational
values
under
normal
service
conditions
and
coded
mes
-
sages
after
an
alarm
condition
or
after
an
over
-
current
trip
operation
.
The
twelve
Green
LEDs
below
the
display
window
indicate
which
value
of
current
,
voltage
,
power
,
power
factor
,
energy
,
or
Total
Harmonic
Distortion
(
THD
)
is
being
displayed
.
The
value
in
the
display
window
indi
-
cates
the
present
value
of
the
parameter
whose
LED
is
lighted
“
Green
"
.
In
Fig
.
1
,
the
first
four
“
Green
”
LEDs
identify
which
current
(
kA
)
value
is
being
displayed
,
i
.
e
.
phase
A
current
(
lA
)
,
phase
B
current
(
lB
)
,
phase
C
cur
-
rent
(
lc
)
,
ground
current
(
lG
)
,
or
current
in
the
fourth
pole
(
neutral
)(
lD
)
.
The
press
and
release
operation
of
the
“
Step
”
push
-
button
will
step
next
to
the
Green
LEDs
that
identify
the
breaker
’
s
phase
to
phase
voltages
being
dis
-
played
;
i
.
e
.
,
(
VAB
)
,
(
VBC
)
,
(
VCA
)
.
Values
are
in
volts
RMS
.
1.1
.
5
Zone
Interlocking
Zone
Selective
Interlocking
(
or
Zone
Interlocking
)
is
avail
-
able
(
see
Fig
.
2
)
for
Digitrip
RMS
Trip
Units
having
Short
Delay
and
/
or
Ground
Fault
protection
.
Zone
Selective
Interlocking
provides
the
fastest
possible
tripping
for
faults
within
the
breaker
’
s
zone
of
protection
,
and
yet
also
provides
positive
coordination
among
all
breakers
in
the
system
(
mains
,
ties
,
feeders
and
downstream
breakers
)
to
limit
the
outage
to
the
affected
part
of
the
system
only
.
When
Zone
Interlocking
is
enabled
,
a
fault
within
the
breaker
’
s
zone
of
protection
will
cause
the
Trip
Unit
to
:
•
Trip
the
affected
breaker
instantaneously
,
and
•
Send
a
signal
to
upstream
RMS
Digitrip
Trip
Units
to
restrain
from
tripping
immediately
.
The
restraining
signal
causes
the
upstream
breakers
to
follow
their
set
coordination
times
,
so
that
only
the
minimum
ser
-
vice
is
disrupted
,
while
the
fault
is
cleared
in
the
shortest
time
possible
.
E
:
T
*
N
Effective
May
1997
Courtesy of store.ips.us

I
.
L
.
29
-
889
A
Page
8
A
repeat
press
and
release
of
“
Step
”
pushbutton
will
pro
-
ceed
to
the
four
Green
LEDs
that
identify
Peak
Power
Demand
(
MW
)
,
Present
Power
Demand
(
MW
)
,
Energy
Demand
(
MWh
)
,
and
Power
Factor
(
PF
)
.
The
next
press
and
release
of
“
Step
”
push
-
button
will
show
the
(
THD
)
for
phase
(
lA
)
current
.
Notice
that
both
the
green
LEDs
(
THD
)
and
(
lA
)
are
illuminated
.
Repeating
“
Step
”
push
-
button
operation
will
show
(
THD
)
values
for
(
lB
)
and
(
lc
)
currents
.
Repeating
press
and
release
one
more
time
will
sequence
back
from
the
(
THD
)
of
(
lc
)
to
the
(
kA
)
cur
-
rent
of
(
lA
)
.
See
Section
1.2
.
1.4
for
displaying
per
har
-
monic
data
.
TABLE
2
-
DIGITRIP
RMS
910
INFORMATION
FUNCTIONS
Trip
Unit
TYPE
RMS
DIGITRIP
910
SS
S
9
99
2
3
3
3
3
LLL
I
S
S
ss
s
9
9
9
4
5
6
3
3
3
LLL
I
S
S
G
G
l
1
Refer
to
I
.
L
Section
Number
Catalog
Number
i
G
Suffix
Number
91
92
93
94
95
96
Instruction
Leaflet
No
.
I
.
L
29
-
889
4
-
Character
LED
Display
XXX
XXX
12
Current
Values
:
1.2
.
1.1
Phase
A
Current
[
la
]
(
kA
)
Phase
B
Current
[
lb
]
(
kA
)
Phase
C
Current
[
lc
]
(
kA
)
XXX
XXX
XXX
XXX
XXX
XXX
Ground
Current
[
Ig
]
(
kA
)
Neutral
Current
[
Id
]
(
kA
)
XXX
1.2
.
1.1
Instrumentation
-
Current
Values
During
the
normal
service
conditions
,
with
the
circuit
breaker
closed
,
the
Digitrip
910
serves
as
an
ammeter
,
displaying
the
individual
phase
currents
(
lA
,
lB
,
lc
)
and
ground
current
(
lG
)
or
the
fourth
pole
(
neutral
)
current
(
lD
)
,
provided
the
circuit
breaker
is
set
up
for
ground
or
fourth
pole
protection
.
Current
values
are
displayed
in
kA
.
The
value
displayed
is
current
in
the
pole
(
or
ground
)
indi
-
cated
by
the
“
Green
”
LED
that
is
turned
“
On
”
.
Press
and
release
the
(
Black
)
“
STEP
”
push
-
button
to
view
the
val
-
ues
of
current
in
the
other
phases
.
(
See
Fig
.
1
.
)
The
range
,
accuracy
and
wave
shape
parameters
for
current
values
displayed
are
:
RANGE
:
0
to
9.999
kA
if
ln
x
<
1000
A
Oto
99.99
kA
if
ln
>
1000
A
ASSUMES
:
5
%
<
Current
<
100
%
of
Frame
Rating
for
Series
C
®
R
-
Frame
or
Type
SPB
circuit
breaker
.
or
5
%
<
Current
<
100
%
of
[
Current
]
Sensor
Rating
for
Type
DS
circuit
breaker
.
ACCURACY
:
±
±
2
%
of
Frame
Rating
for
Series
C
®
R
-
Frame
or
Type
SPB
circuit
breakers
,
or
±
±
2
%
of
[
Current
]
Sensor
Rating
for
Type
DS
circuit
breaker
.
1.2
1.1
n
n
n
1.2
.
1.2
Voltage
Values
:
Phase
[
VAB
]
(
volts
)
Phase
[
VBC
]
(
volts
)
Phase
[
VCA
]
(
volts
)
XXX
XXX
XXX
XXX
XXX
XXX
Power
.
Power
Factor
and
Energy
Values
:
1
2.1
.
3
XXX
XXX
XXX
XXX
XXX
XXX
Peak
Power
Demand
(
MW
)
Present
Power
Demand
(
MW
)
Reverse
Power
Flow
XXX
XXX
1
2.1
3
Power
Factor
XXX
XXX
XXX
XXX
Energy
Consumption
(
MWh
)
Reverse
Energy
Consumption
1.2
.
1
3
Harmonic
Currents
:
1.2
1
4
Total
Harmonic
Distortion
[
THD
]
Per
Harmonic
XXX
XXX
XXX
XXX
TABLE
3
Local
Messages
:
DISC
=
Discriminator
Trip
EXTT
=
EXTernal
Trip
GNDT
=
GrouND
Trip
X
X
XXX
XXX
XXX
XXX
X
X
XXX
XXX
HILD
=
High
LoaD
Alarm
INST
=
INStantaneous
Trip
LDPU
=
Long
-
Time
Delay
Pick
-
U p
X
X
XXX
XXX
XXX
XXX
XXX
LDT
=
Long
-
Time
Delay
Trip
NPOW
=
Negative
POWer
flow
ORID
=
OverRIDe
Trip
11
1
11
1
XXX
XXX
XX
XXX
XXX
XX
ORNG
=
OverRaNGe
Trip
PLUG
=
Rating
PLUG
Problem
SDT
=
Short
-
Time
Delay
Trip
XXX
XXX
TEMP
=
OverTEMPerature
Trip
TEST
=
TEST
ready
t o
begin
XXX
XXX
TABLE
3
LEGEND
:
X
=
Function
Included
n
=
Circuit
Breaker
must
be
equipped
for
Neutral
Protection
1
=
n
/
a
for
Type
DS
Breakers
1.2
.
1.2
Instrumentation
-
Voltage
Values
During
the
normal
service
conditions
,
with
the
circuit
breaker
closed
,
the
Digitrip
910
serves
as
a
voltmeter
displaying
the
breaker
’
s
phase
to
phase
voltages
(
VAB
)
,
(
VBC
)
,
and
(
VCA
)
.
The
range
and
accuracy
for
the
voltage
values
displayed
are
:
RANGE
:
100
to
600
VAC
RMS
-
3
Phase
ACCURACY
:
±
2
%
of
Full
Range
Volts
Effective
May
1997
Courtesy of store.ips.us

I
.
L
.
29
-
889
A
Page
9
TABLE
3
-
DIGITRIP
RMS
910
TRIP
UNIT
MESSAGE
CODES
AND
THEIR
MEANINGS
MESSAGE
MEANING
COMMENT
SEC
.
DISC
Discriminator
Trip
!
(
High
initial
Current
Release
)
EXTernal
Trip
Breaker
tripped
because
phase
current
exceeded
11
x
rating
plug
current
ln
Value
1
1 3
EXTT
Breaker
tripped
due
to
external
communications
control
signal
-
for
example
5.8
from
IMPACC
'
M
GNDT
GrouND
-
fault
Jrip
-
S
Breaker
tripped
because
ground
current
exceeded
Ground
Fault
protection
settings
Phase
current
has
exceeded
85
%
of
Long
-
Time
Current
Setting
for
more
than
40
seconds
3
8
3
9
HILD
High
LoaD
Alarm
ALARM
:
Nearing
Overload
Condition
App
'
x
B
Casef
INST
INStantaneous
TripaT
Breaker
tripped
instantaneously
because
phase
current
exceeded
Instantaneous
protection
setting
Phase
current
has
exceeded
Long
-
Time
current
setting
.
Trip
unit
is
timing
to
trip
breaker
.
3.6
Long
-
Time
Delay
Pick
-
Up
ALARM
:
Overload
Condition
in
Progress
Long
-
Time
Delay
Iripv
4
(
Overload
Trip
)
Negative
POWer
flow
LDPU
3.2
LDT
Breaker
tripped
because
phase
current
exceeded
Long
-
Time
protection
settings
Power
is
flowing
into
“
load
”
side
(
bottom
)
of
breaker
,
and
out
from
“
line
"
side
(
top
)
of
the
breaker
.
Breaker
tripped
instantaneously
because
phase
current
exceeded
short
-
time
rating
of
circuit
breaker
Value
of
current
exceeds
display
capability
3
2
,
3
3
NPOW
1 2
1 3
OverRIDe
Trip
X
.
3
ORID
1.1
4
Qver
RaNGe
Trip
£
3
.
(
Current
too
high
to
measure
.
)
Rating
PLUG
Problem
1.2
.
2
ORNG
Rating
Plug
is
missing
,
damaged
,
or
not
well
connected
.
If
breaker
is
closed
,
it
will
trip
,
and
the
instantaneous
/
override
LED
will
light
.
If
breaker
is
open
,
it
will
not
close
.
Protection
functions
still
operate
,
but
may
be
up
to
12
%
out
-
of
-
tolerance
.
Replace
trip
unit
at
first
opportunity
.
Breaker
tripped
because
phase
current
exceeded
Short
-
Time
Delay
protection
settings
Breaker
tripped
because
ambient
temperature
of
SURE
+
chip
exceeded
95
degrees
C
A
trip
test
will
begin
as
soon
as
you
release
the
push
to
test
button
and
'
‘
TEST
'
message
will
disappear
.
The
breaker
will
trip
,
and
the
cause
of
trip
is
displayed
.
A
No
Trip
Unit
test
will
begin
as
soon
as
you
release
push
to
test
button
,
and
the
display
shows
the
elapsed
time
of
test
.
1.3
PLUG
1
22
1
Nonfatal
memory
error
ROM
ERROR
..
.
3
4
.
3.5
Short
-
Time
Delay
Tip
*
SDT
Ove
rTE
M
Perat
u
re
Trip
1.1
TEMP
4
0
TEST
and
trip
breaker
is
ready
to
begin
TEST
40
Test
(
without
tripping
breaker
)
is
ready
to
begin
[
blank
]
or
1
4
Control
power
is
not
available
,
or
wrong
potential
applied
Trip
Unit
does
not
calculate
THD
values
because
of
a
protection
related
activity
.
Trip
unit
not
“
ON
"
1 2
1 4
Aborted
THD
Calculation
NOTES
:
1
In
the
case
of
a
high
-
level
fault
condition
,
the
Trip
Unit
will
operate
whenever
a
complete
RMS
current
value
exceeds
the
trip
level
.
For
this
reason
,
the
displayed
value
may
be
less
than
the
actual
RMS
fault
current
.
2
In
the
case
of
a
very
high
fault
current
,
the
message
“
ORNG
”
(
indicating
over
range
)
appears
because
the
Trip
Unit
cannot
display
the
actual
value
of
the
fault
current
.
^
OverRIDe
(
Fixed
Instantaneous
)
Trip
is
for
type
LS
and
LSG
Trip
Units
(
no
Instantaneous
element
)
,
on
circuit
breakers
whose
Short
-
Circuit
current
interrupting
capability
exceeds
their
Short
-
Time
Current
withstand
capability
.
(
See
Section
1.1
.
4
)
4
The
values
of
the
currents
displayed
after
a
TRIP
event
,
are
the
values
at
the
time
the
TRIP
operation
was
initiated
.
Although
the
magnitude
of
a
fault
current
,
for
example
,
can
continue
to
increase
after
the
TRIP
operation
is
initiated
,
those
values
of
current
occurring
after
the
TRIP
operation
is
initiated
,
are
not
displayed
.
REVERSE
FED
IN
APPLICATION
.
THEREFORE
DO
NOT
RELY
UPON
THE
VOLTAGE
READOUT
AS
A
SOLE
INDICATOR
OF
THE
BREAKER
’
S
OA
/
/
OFFSTA
-
TUS
OR
BREAKER
’
S
VOLTAGE
STATUS
.
£
^
CAUTION
WHEN
THE
CIRCUIT
BREAKER
’
S
CONTACTS
ARE
OPEN
IT
MAY
OR
MAY
NOT
DISPLAY
THE
BREAKER
’
S
PHASE
TO
PHASE
VOLTAGES
.
THIS
DEPENDS
ON
THE
TYPE
BREAKER
.
THE
TYPE
DS
BREAKERS
PICK
UP
THE
PT
MODULE
’
S
CONNEC
-
TIONS
ON
THE
TOP
SIDE
WHILE
THE
TYPES
SPB
AND
RD
BREAKERS
PT
MODULE
IS
CONNECTED
TO
THE
BOTTOM
SIDE
-
SEE
FIG
2
.
A
SECOND
FAC
-
TOR
TO
CONSIDER
IS
WHETHER
THE
BREAKER
IS
1.2
.
1.3
Instrumentation
-
Power
,
Power
Factor
and
Energy
values
The
Digitrip
RMS
910
Trip
Unit
displays
power
and
energy
values
.
By
using
the
circuit
breaker
current
sen
-
sors
and
an
integrally
mounted
Potential
Transformer
Module
shown
in
Fig
.
6
,
power
and
energy
values
are
F
:
T
’
N
Effective
May
1997
Courtesy of store.ips.us

I
.
L
.
29
-
889
A
Page
10
computed
and
displayed
in
the
four
-
digit
display
window
on
the
face
of
the
Trip
Unit
.
The
power
,
power
factor
and
energy
parameter
values
displayed
in
the
window
on
the
face
of
the
Trip
Unit
include
:
•
Peak
Demand
in
MW
(
Megawatts
)
•
Present
Demand
in
MW
(
Megawatts
)
•
Energy
(
Consumed
)
in
MWh
(
Megawatt
-
hours
)
•
Power
Factor
Four
“
Green
”
LEDs
as
shown
in
Fig
.
1
are
provided
to
indicate
which
value
is
displayed
.
The
same
“
STEP
”
push
-
button
pressed
and
released
to
view
the
different
values
of
current
and
voltage
is
also
pressed
and
released
to
view
the
power
,
power
factor
and
energy
val
-
ues
.
The
Peak
Demand
parameter
is
based
on
a
sampling
window
of
fifteen
(
15
)
minutes
.
Power
is
repeatedly
aver
-
aged
over
this
interval
and
the
maximum
average
is
dis
-
played
as
Peak
Demand
.
The
demand
window
is
not
a
“
sliding
window
”
.
It
is
more
like
a
“
jumping
window
”
.
When
the
Trip
Unit
is
first
energized
,
there
is
a
delay
of
15
minutes
before
the
first
non
-
zero
value
is
displayed
.
To
reset
the
peak
demand
value
shown
in
the
display
win
-
dow
back
to
zero
,
press
and
release
the
(
Black
)
“
Demand
Reset
”
push
-
button
,
shown
adjacent
to
the
“
Peak
Demand
”
label
in
Fig
.
1
.
Note
:
The
peak
demand
function
requires
that
120
VAC
control
power
be
supplied
to
the
Power
/
Relay
Module
.
The
Present
Demand
is
a
power
value
averaged
over
approximately
one
second
.
To
view
the
“
Present
Demand
”
value
in
the
display
window
,
press
and
release
the
“
STEP
”
push
-
button
several
times
until
the
LED
next
to
“
Present
MW
”
is
lighted
.
The
range
,
assumptions
and
accuracy
parameters
for
peak
and
present
power
demand
values
displayed
are
:
RANGE
:
0
to
9.999
MW
ASSUMES
:
5
%
<
Current
<
175
%
of
the
Plug
Rating
ln
SAMPLING
WINDOW
:
15
min
.
for
Peak
Demand
,
-
1
sec
.
for
Present
Demand
ACCURACY
:
range
assumptions
and
accuracy
for
the
system
power
factor
function
values
are
:
from
0.5
(
lagging
)
to
0.5
(
leading
)
balanced
three
-
phase
load
,
per
ANSI
Std
.
C
12.1
-
1988
>
20
%
of
Frame
Rating
for
Series
C
“
R
-
Frame
or
Type
SPB
circuit
breakers
.
>
20
%
of
[
Current
]
Sensor
Rating
for
Type
DS
circuit
breakers
.
±
0.02
The
Energy
parameter
is
the
summation
of
the
average
power
over
time
and
it
is
expressed
in
megawatt
-
hours
(
MWh
)
.
The
value
is
updated
approximately
once
a
sec
-
ond
.
The
value
cannot
be
reset
locally
.
After
the
maxi
-
mum
value
is
reached
,
the
display
automatically
rolls
over
to
zero
.
The
range
and
accuracy
parameters
for
energy
demand
values
displayed
are
:
RANGE
:
RANGE
:
ASSUMES
:
CURRENT
:
CURRENT
:
ACCURACY
:
Oto
999.9
MWh
if
ln
<
1000
A
Oto
9999
MWh
if
ln
>
1000
A
5
%
<
Current
<
175
%
of
the
Plug
Rating
ln
±
5
%
of
(
Frame
Rating
x
600
V
x
time
)
for
Series
C
®
R
-
Frame
or
Type
SPB
circuit
breakers
,
±
5
%
of
(
Current
Sensor
Rating
x
600
V
x
time
)
for
Type
DS
circuit
breakers
.
The
energy
value
is
stored
in
the
Trip
Unit
memory
.
As
long
as
the
120
VAC
control
power
is
maintained
to
the
Power
/
Relay
Module
,
it
can
be
viewed
.
If
the
120
VAC
control
power
is
lost
and
then
is
restored
,
the
Energy
value
is
restored
too
.
The
Digitrip
RMS
910
Trip
Unit
presumes
that
power
is
flowing
into
the
“
top
”
and
out
of
the
bottom
of
the
circuit
breaker
(
positive
flow
of
power
)
.
If
the
power
flows
in
the
opposite
direction
,
i
.
e
.
,
bottom
to
top
,
the
value
of
power
will
not
be
displayed
continuously
.
Instead
,
the
power
value
in
the
display
window
will
alternate
with
the
coded
message
“
NPOW
”
.
This
message
,
alternating
with
the
value
,
indicates
power
flowing
out
of
the
top
of
the
circuit
breaker
.
This
condition
will
occur
when
a
Main
circuit
breaker
is
“
reverse
fed
”
and
can
frequently
occur
for
three
breaker
schemes
that
involve
a
“
tie
”
breaker
.
The
“
NPOW
”
message
can
be
defeated
on
type
DS
and
type
SPB
breakers
only
by
inserting
an
appropriate
"
jumper
”
.
(
See
wiring
diagram
for
your
type
of
circuit
breaker
listed
in
Section
6
.
)
ASSUMES
:
ACCURACY
:
or
±
4
%
of
(
Frame
Rating
x
600
V
)
for
Series
C
®
R
-
Frame
or
Type
SPB
circuit
breakers
,
±
4
%
of
(
Current
Sensor
Rating
x
600
V
)
for
Type
DS
circuit
breakers
.
The
System
Power
Factor
(
PF
)
is
a
unitless
parameter
that
is
displayed
locally
on
the
Digitrip
RMS
910
.
The
or
FiT
-
N
Effective
May
1997
Courtesy of store.ips.us