ABB CIRCUIT SHIELD 87T - Page 2

IB
7.6
.
1.7
-
4
Page
2
Transformer
Differential
Relay
TABLE
OF
CONTENTS
Introduction
Precautions
Placing
Relay
into
Service
App
1
ication
Data
Maintenance
and
Testing
.
.
.
Page
2
Page
2
Page
2
Page
5
Page
14
INTRODUCTION
These
instructions
contain
the
information
required
to
properly
install
,
operate
,
and
test
the
ABB
Circuit
-
Shield
Type
87
T
single
-
phase
Transformer
Differential
Relay
.
These
mounting
.
the
case
and
clearly
numbered
.
relays
are
housed
in
a
case
suitable
for
conventional
semi
-
flush
panel
All
connections
to
the
relay
are
made
at
terminals
located
on
the
rear
of
Relays
with
catalog
numbers
starting
with
419
are
similar
in
function
to
relays
of
the
earlier
219
series
,
but
offer
totally
drawout
construction
with
integral
test
faci
1
ities
.
and
blade
assembly
upon
removal
of
the
relay
from
its
case
,
are
of
partial
drawout
construction
,
with
the
input
transformers
remaining
in
the
case
upon
withdrawal
of
the
lower
electronic
circuit
board
.
Current
transformer
shorting
is
accomplished
by
a
direct
-
acting
spring
Units
of
the
219
series
PRECAUTIONS
The
following
precautions
should
be
taken
when
applying
these
relays
:
1
.
Incorrect
wiring
may
result
in
damage
,
diagram
before
energizing
,
correct
polarity
.
Be
sure
wiring
agrees
with
the
connection
Be
sure
that
the
dc
control
voltage
is
applied
in
the
2
.
Apply
only
the
rated
dc
control
voltage
marked
on
the
front
panel
.
3
.
Do
not
attempt
to
change
a
current
tap
setting
while
the
relay
is
in
service
.
This
wi
11
likely
cause
the
relay
to
trip
due
to
the
mismatch
created
.
(
Pulling
the
tap
pin
does
not
open
the
ct
circuit
.
)
If
a
control
wiring
insulation
test
is
4
.
High
voltage
tests
are
not
recommended
,
required
,
withdraw
the
unit
from
its
case
before
applying
the
test
voltage
.
5
.
Follow
test
instructions
to
verify
that
the
relay
is
in
proper
working
order
.
CAUTION
:
since
troubleshooting
entails
working
with
energized
equipment
,
care
should
be
taken
to
avoid
personal
shock
.
Only
competant
technicians
familiar
with
good
safety
practices
should
service
these
devices
.
PLACING
THE
RELAY
INTO
SERVICE
1
.
RECEIVING
.
HANDLING
.
STORAGE
Upon
receipt
of
the
relay
(
when
not
included
as
part
of
a
switchboard
)
examine
for
shipping
damage
.
If
damage
or
loss
is
evident
,
file
a
claim
at
once
and
promptly
notify
Asea
Brown
Boveri
.
Use
normal
care
in
handling
to
avoid
mechanical
damage
.
Keep
the
relay
clean
and
dry
.
2
.
INSTALLATION
the
outline
dimensions
and
panel
drilling
are
given
in
Figure
1
.
Mounting
:
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