ABB MMCO-2 - Page 3

I
.
L
.
41
-
121.2
2.5
.
DISPLAY
MODULE
•
Input
/
Output
(
I
/
O
)
The
Display
module includes
(
see
Figure
3
)
:
2.1
.
POWER
SUPPLY
The
Power
Supply
is
available
in
two
versions
:
48
to
125
Vdc
or
250
Vdc
.
The Power
Supply
module
con
-
tains
components
of
a
dc
/
dc
converter
,
an
ABB
cus
-
tom
linear
IC
,
a
+
5
Volt
reference
and
adjustment
potentiometers
for
the
+
5
V
reference
,
dc
/
dc
con
-
verter
converts
48
-
125
Vdc
or
250
Vdc
to
21
Vdc
and
5
Vdc
.
A
16
x
2
character
alphanumeric
LCD
for
display
of
the last
four
trip
targets
,
settings
,
metering
,
relay
cat
-
alog
number
,
software
versions
,
and time
and date
(
optional
)
.
A
red
“
TRIP
”
LED
which blinks
when
input
current
is
above time
-
delay
pickup
level
;
is
steady
for
time
-
delay
or
instantaneous
trip
;
and seals
-
in
when
breaker
trip
current
flow
is
detected
.
2.2
.
CURRENT
TRANSFORMER
(
CT
)
The
ct
module
contains
a
current
transformer for
each
phase
and
ground
input
,
as
well
as
input
wave
-
form
conditioning
and
surge
protection
.
Ct
module
outputs
are
sent
to
the
Microprocessor
module
.
An
amber
“
MONITOR
”
LED
which is
“
ON
”
during
nor
-
mal
relay
operation
,
for
power
-
on
and
self
-
check
indi
-
cation
.
This
LED will
be
“
OFF
”
if
there
is
a
relay
hardware
failure
or
alarm condition
.
2.3
.
MICROPROCESSOR
The
Microprocessor
module
contains
a
microcom
-
puter
chip
which includes
an
analog
to
digital
(
A
/
D
)
converter
,
input
and
output ports
and
timers
.
The
module also
includes
memory
,
a
real
-
time
clock
(
optional
)
.
Relay
pickup
calibration
is
part
of
this
module
,
as
well
as
a
trimmer
capacitor
for
adjust
-
ment
of
the
optional
real
-
time
clock
.
There
are
five
keypad
push
-
buttons
as
follows
:
1
)
“
SELECT
”
button
(
SW
1
)
.
Selects
between
the
settings
mode
,
targets
dis
-
play
,
time
setting
and
metering display
.
2
)
“
SCROLL
”
button
(
SW
2
)
.
Accesses
the
different
categories
within
each
mode
.
3
&
4
)
“
RAISE
”
(
SW
3
)
and
“
LOWER
”
(
SW
4
)
buttons
.
Select
the
actual value
of
the
parameter
in
the
settings
mode
.
When
“
RAISE
”
or
“
LOWER
”
has
been
pushed
,
it
is
not
possible
to
“
SELECT
”
or
“
SCROLL
”
new
parameters
without
pushing
“
ENTER
”
first
.
2.4
.
INPUT
/ OUTPUT
The INPUT
/
OUTPUT
module
contains
contact
clo
-
sure
outputs
and
optically
isolated
inputs
.
A
reed
relay
detects the
trip
current
flow
through
trip
con
-
tacts
.
2.4
.
1
.
Contact
Closure
Outputs
(
See Section
6.6
)
(
TDTRIP
)
(
ITRIP
)
(
TDANUNLO
)
(
IANUNLO
)
(
ALARMLO
)
5
)
“
ENTER
”
button
(
SW
8
)
.
Relay
accepts
the
setting
which is shown
on
the
alphanumeric
display
.
In
addition
,
there
are
three other external buttons
that
are
activated
as
follows
:
Time
Delay
Trip
Instantaneous
Trip
Time
Delay
Annunciator
Instantaneous
Annunciator
Alarm
Output
2.4
.
2
.
Optically
-
Isolated
Inputs
(
w
/
Directional
Control
Option
)
Phase Directional
Control
Ground
Directional
Control
“
EXTERNAL
SCROLL
”
button
(
SW
7
)
.
Can
be
pushed
without
opening
the
relay
case
.
This button scrolls the
display
.
“
TARGET RESET
button
(
SW
6
)
.
Can
be
reset
without
opening
the
relay
case
.
This button
resets
the
trip
LED
if
the
trip
LED
has
been
sealed
-
in
by
breaker
trip
current
flow
.
All
target
information
(
16
targets
stored
in
the
relay
)
1
.
(
TCP
)
(
TCG
)
2
.
2.4
.
3
.
Optically
-
isolated
Inputs
(
w
/
Remote
Reset
Option
)
Remote Reset
(
RR
)
3
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