GE IRT51E User manual

GEK
-
86038
C
INSTRUCTIONS
TEMPERATURE
RELAY
TYPES
:
IRT
51
E
IRT
51
F
IRT
51
G
IRT
51
H
GENERAL
ELECTRIC
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GEK
-
86038
CONTENTS
PAGE
DESCRIPTION
3
INTRODUCTION
3
APPLICATION
4
RATINGS
6
BURDENS
8
CONSTRUCTION
9
RECEIVING
,
HANDLING
AND
STORAGE
10
INSTALLATION
PROCEDURE
10
OPERATING
UNIT
VOLTAGE
CONNECTIONS
AUXILIARY
CIRCUIT
CONNECTIONS
.
.
..
RTD
CONNECTIONS
11
11
13
INSPECTION
,
ACCEPTANCE
TESTS
,
PERIODIC
CHECKS
AND
ROUTINE MAINTENANCE
14
14
VISUAL
INSPECTION
MECHANICAL
INSPECTION
AND
ADJUSTMENTS
CONTACT INSPECTION
AND
CLEANING
AUXILIARY
BRUSHES
RHEOSTAT
CLEANING
ELECTRICAL
TESTS
15
16
16
16
16
CALIBRATION
PROCEDURE
18
20
RENEWAL
PARTS
21
LIST
OF
TABLES
2 2
LIST
OF
ILLUSTRATIONS
2
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GEK
-
86038
TEMPERATURE
RELAY
TYPES
:
IRT
51
E
IRT
51
F
IRT
51
G
IRT
51
H
DESCRIPTION
INTRODUCTION
The
type
IRT
temperature
sensing
relays
are
designed
for
use
with
single
element
,
three
lead
,
resistance
temperature
detectors
(
RTD
)
.
Models
are
available
for
use
with
the
following
specific
type
RTD
:
a
.
10
ohm
at
25
°
C
copper
RTD
b
.
100
ohm
at
0
°
C
platinum
RTD
c
.
120
ohm
at
0
°
C
nickel
RTD
The
models
are
listed
in
Table
1
.
The
type
IRT
relays
will
provide
overtemperature
protection
,
either
trip
or
alarm
,
for
any
apparatus
that
is
equipped
with
one
of
the
listed
RTDs
.
continuously
adjustable
over
a
temperature
sensing
range
of
80
°
C
to
165
°
C
.
The
relays
are
These
relays
are
of
the
wattmetric
induction
disk
type
and
provide
various
contact
combinations
as
described
below
.
The
measuring
circuit
is
similar
to
a
Wheatstone
Bridge
,
except
that
two
adjacent
legs
of
the
bridge
are
replaced
by
transformer
secondary
windings
.
The
primary
winding
of
this
transformer
forms
the
polarizing
coil
of
the
wattmetric
unit
.
The
type
IRT
51
E
relay
is
an
overtemperature
sensing
relay
having
a
single
normally
-
open
contact
,
with
a
target
seal
-
in
unit
,
as
shown
in
Figure
7
.
The
relay
is
furnished
in
a
single
end
,
small
size
drawout
case
.
The
IRT
51
F
relay
is
an
overtemperature
sensing
relay
having
both
normally
-
open
and
normally
-
closed
output
contacts
.
These
contacts
are
provided
by
an
auxiliary
unit
(
A
)
operating
from
the
main
induction
disk
unit
contacts
in
a
pickup
,
seal
-
in
knock
down
circuit
,
as
shown
in
Figure
8
.
The
relay
is
self
-
resetting
when
the detected
temperature
falls
below
a
preselected
level
.
This
reset
temperature
is
continuously
adjustable
over
a
range
from
5
°
C
to
30
°
C
below
the
set
operating
temperature
.
A
manual
reset
target
is
included
,
which
is
operated
by
a
contact
of
the
auxiliary
unit
A
.
The
relay
is
mounted
in
a
single
end
,
small
size
drawout
case
.
The
type
IRT
51
G
is
an
overtemperature
sensing
relay
providing
two
normally
-
open
and
two
normally
-
closed
electrically
separate
output
contacts
,
provided
by
a
two
-
position
latching
relay
whose
operating
coil
(
OP
)
and
reset
coil
(
RE
)
are
controlled
by
the
left
-
hand
(
IRT
|
_
)
and
right
-
hand
(
IRTR
)
contacts
,
respectively
,
of
These
contacts
are
These
instructions
do
not
purport
to
cover
all details
or
variations
in
equipment
nor
to
provide
for
every
possible
contingency
to
be
met
in
connection
with
installation
,
further
information
be
desired
or
should
particular problems
arise
which
are
not
covered
sufficiently
for
the
purchaser
'
s
purposes
,
the
matter
should be
referred
to
the
General
Electric
Company
.
To
the
extent
required
the
products
described
herein
meet
applicable
ANSI
,
but
no
such
assurance
is
given
with
respect
to
local
codes
and ordinances
because
they
vary
greatly
.
Should
operation
or
maintenance
.
IEEE
and
NEMA
standards
;
3
Courtesy of NationalSwitchgear.com

GEK
-
86038
the
main
induction disk unit
,
as
shown
in
Figure
9
.
The
relay
operates
to
close
the
normally
-
open
output
contacts
whenever
the
detected
temperature
exceeds the
set
value
.
These
output
contacts
can
be
reset
:
a
.
manually
b
.
electrically
c
.
self
-
reset
by
means
of
external
connections
but
only
after
the detected
temperature
has
fallen
below
the
reset
temperature
of
the
main
unit and its
right
-
hand
(
IRTR
)
contact
has
closed
.
The
reset
level
of
the
main
unit
is
continuously
adjustable
from
5
oc
to
30
oc
below
its
operating
temperature
level
.
The
IRT
51
G
relay
is
mounted
in
a
double end
,
small
size drawout
case
.
The
type
IRT
51
H
is similar
to
the
IRT
51
G
except
an
RTD
probe
assembly
is
furnished
as
a
part
of
the
relay
model
.
The
probe
is
a
three
wire
,
single
element
,
tip
sensitive
,
100
ohm
at
OOC
,
platinum
RTD
.
The
probe
comes
with
a
fluid
seal
installation
fitting
and also
a
brass
reducing
fitting
for
use
where
required
(
see
INSTALLATION
PROCEDURE
)
.
APPLICATION
The
type
IRT
51
relays
can
be used
to
protect
any
apparatus
equipped
with
one
of
the
resistance
temperature
detectors
listed
in
the
INTRODUCTION
section
.
The
types
IRT
51
E
and
IRT
51
F
relays
are
intended
primarily
for
the
protection
of
motors
or
generators
having
the
RTD
'
s
embedded
in
the
windings
.
The
usable
temperature
range
of
80
°
C
to
165
°
C
makes them
particularly
suitable
for
application
on
machines
with
class
A
,
B
or
F
insulation
,
transformers
against
overheating
with
associated
RTD
’
s
placed
in
strategic
locations
in
the
tank
.
These
relays
may
also be
applied
to
protect
power
Typical
external
connections
for
the
type
IRT
51
E
relay
are
shown
in
Figure
10
.
Typical
external
connections
for
the
type
IRT
51
F
relay
are
shown
in
Figure
11
.
The
types
IRT
51
G
and
IRT
51
H
relays
are
intended
primarily
for
bearing
temperature
protection
of
rotating
equipment
.
Typical
external
connections
for
these
relays
are
shown
in
Figure
12
.
The
functions
that
temperature
relays
perform
depend
upon
the
type
of
equipment
to
be
protected
,
its
importance
to
the
system
,
and
its
location
in
the
system
.
In
unattended
stations
,
for
example
,
the
IRT
51
E
or
IRT
51
F
relays operating
from
embedded
RTD
'
s
may
be used
to
reduce
or remove
load
automatically
.
The
type
IRT
51
F
with
its
normally
-
open
(
IRT
[
_
)
and
normally
-
closed
(
IRTR
)
contacts
could
also
be
employed
to
prevent
an
increase
in
load until
the
temperature
has
returned
to
an
acceptable
level
.
In
attended
stations
,
the
function
of
these
relays
is
generally
to
provide
a
warning
alarm
that
an
overtemperature
condition
exists
,
especially
in
the
case
of
major
units
and
essential
auxiliary
power
equipment
.
In
addition
to
sounding
an
alarm
,
the
relays
may
also
initiate
a
timing
device which
causes
a
delayed
automatic
corrective action
if
the
station
operator
has
not
responded
to
the
alarm
within
a
reasonable
time
.
These
relays
should
not
be
used
to
determine
machine
load
,
since
operating
temperature
is
not
necessarily
a
reliable
indication
of
maximum
permissible
load
.
Other
design
limitations
may
place
more
stringent
restrictions
on
machine
rating
.
Courtesy of NationalSwitchgear.com

GEK
-
86038
TABLE
1
RELAY
MODEL
DESCRIPTION
TABLE
C
<
C
C
c
CVJ
ro
LU
LU
LU
LL
LL
LL
UJ
<
c
c
LD
UD
LL
.
Uu
U
_
C
C
C
r
-
H
<
XJ
OO
CD
CD
CD
<
CD
C
\
J
ro
eg
O
cc
s
:
LU
=
c
pH
I
—
1
CQ
LD
LD
in
LD LD
LD
LD
LO
LO
LO
LO LO
LO
>
-
S
C
ZD
CC
cc
cc
cc cc
cc
cc
cc
cc
CC
CC
CC
cc
—
J
z
LU
eg
og
eg eg
c
\
j
eg
eg
eg
OJ
eg
eg eg
eg
cc
For
use
with
:
10
ohm
@
250
C
copper
RTD
100
ohm
@
0
OC
platinum
RTD
120
ohm
@
0
°
C
nickel
RTD
X
X
X
X
X
X
X
X
X
X
X
X
X
RTD
furnished
with
relay
X
Adjustable
overtemperature
range
80
°
C
-
160
°
XXX
XXX
XXX
X
X
X
X
Adjustable
reset
temperature
5
°
-
30
°
C
below
set
operating
temperature
X
XXX
X
X
X
X
XX
Operating
Circuit
120
/
240
VAC
,
50
/
60
Hz
X
XXX
XXX
XXX
Auxi
1
iary
Circuit
120
/
240
VAC
,
50
/
60
Hz
125
/
250
VDC
XXX
XXX
XX
X
X
X
X
X
X
Target
Target
Seal
-
in
0.2
/
2.0
amp
DC
XXX
XXX
XX
X
X
X
XX
Reset
Features
Manually
Electrically
(
remote
)
Self
XXX
XXX
X
X
X
X
X
XXX
XXX
X
X
X
X
Number
of
Contacts
Electrically
Separate
N
.
0
.
Electrically
Separate
N
.
C
.
Convertible
N
.
0
.
or
N
.
C
.
contact
1
1
1
111 111
11
1
2
2
22
2
2
2
2
1
1
1
Internal
Connections
Figure
7
8
8
9
9
Outline
and
Panel
Drilling
Figure
18
18
17 17
17
Operative
Circuit
110
/
220
VAC
50
/
60
Hz
XXX
Auxiliary
Circuit
110
/
220
VAC
40
/
60
Hz
110
/
220
VDC
XXX
5
Courtesy of NationalSwitchgear.com

GEK
-
86038
It
is
important
to
note
that
these
type
IRT
relays
detect actual
temperature
,
not
rise
above ambient
.
The
temperature
setting
should
be
made
on
the
basis
of
long
term
trends
in
ambient
temperature
.
RATINGS
The
operating
unit
of
the
type
IRT
relays
has
a
center
tapped
coil
that
permits
operation
at
either
120
or
240
volts
AC
*
.
For
240
volt
operation
,
the
two
operating
coils
must
be
connected
in
series
.
For
120
volt
operation
,
the
two
operating
coils
must
be
connected
in
parallel
.
See
Figures
10
,
11
and
12
for
the
AC
power
source
connections
.
The
IRT
51
E
and
IRT
51
F
models
have
an
internal
,
insulated standoff
post
for
making
the series connection
,
while the
IRT
51
G
and
IRT
51
H
models
bring
all
of
the
operating
coil
leads
to
separate
terminals external
to
the
relay
.
The
IRT
51
E
and
IRT
51
F
models
are
shipped
from
the
factory
connected
for
240
volt
operation
.
Some
models
of
the
IRT
51
F
(
-
)
A
relay
are
rated
at
110
/
220
VAC
or
DC
.
See
Table
I
.
The
type
IRT
relays
are
suitable
for
operation
on
50
hertz and
60
hertz
power
systems
.
The
type
IRT
relays
are
designed
for
use
with the
following
specific
type
resistance
temperature
detectors
:
10
ohms
at
25
°
C
copper
RTDs
100
ohms
at
0
°
C
planinum
RTDs
120
ohm
at
0
°
C
nickel
RTDs
a
.
b
.
c
.
Use
only
the
specific
RTD
for
which
the
particular
model
IRT
was
designed
.
The
IRT
51
E
,
IRT
51
G
and
IRT
51
H
relays
are
furnished
with
a
target
and seal
-
in
unit
having
taps
for
0.2
amps
DC
and
2.0
amps
DC
operation
,
different
ratings
based
on
tap
settings
.
Table
2
shows
the
TABLE
2
TARGET
SEAL
-
IN
UNIT
RATINGS
O
!
TAP
0.2
+
0
%
|
Minimum
DC
operating
current
0.2
2.0
-
25
°
/
(
ohms
)
(
amps
)
(
seconds
)
(
seconds
)
(
amps
)
DC
resistance
+
10
%
7.0
0.13
i
Tripping
duty
!
Carry
30
amps
Carry
10
amps
j
Carry
continuous
i
Contact
current
closing
rating
(
amps
)
5.0 30.0
0.03 4.0
0.25
30.0
0.3 3.0
30 30
(
volts
Max
.
)
250 250
The
tap
setting
used
on
the seal
-
in
units
is
determined
by
the
current
drawn
by
the
trip
circuit
.
The
0.2
amp
tap
is
for
use
with
trip
circuits
that
operate
on
6
Courtesy of NationalSwitchgear.com

GEK
-
86038
currents
ranging
from
0.2
to
2.0
amps
DC
at
the
minimum
control
voltage
.
If
this
tap
is
used
with
trip
coils
requiring
more
than
2.0
amps
,
there
is
a
possibility
that
the
7.0
ohms
resistance
of
the
target
seal
-
in
unit
will
reduce
the
current
to
such
a
low
value
that
the
breaker
will
not
be
tripped
.
The
2.0
amp
tap
should
be
used
with
trip
coils
that
take
2.0
amps
DC
or
more
at
the
minimum
control
voltage
.
The
tripping
current
should
not
exceed
30
amps
at
the
maximum
control
voltage
.
If
the
tripping
current
exceeds
30
amps
,
an
auxiliary
relay
should
be
used
so
the
tripping
current
does
not
pass
through
the
target
seal
-
in
unit
.
The
IRT
51
F
relay
is
furnished
with
a
target
unit
and
an
auxiliary
telephone
type
relay
.
The
auxiliary
circuit
may
be
used
with
120
or
240
volts
AC
,
50
or
60
hertz
,
or
with
125
or
250
volts
DC
*
.
A
voltage
level
selection
link
is
located
inside
of
the
relay
on
top
of
the
resistor
mounting
plate
,
and
is
marked
"
LOW
"
for
120
and
125
volts
,
and
"
HIGH
"
for
240
and
250
volts
.
This
link
must
be
in
the
position
corresponding
to
the
voltage
level
being
applied
.
The
IRT
51
F
relay
is
shipped
from
the
factory
with
the
link
in
the
"
HIGH
"
position
.
Some
models
of
the
IRT
51
F
(
-
)
A
relay
are
rated
at
110
/
220
VAC
or
DC
.
*
See
Table
I
.
The
target
shows
whenever
an
overtemperature
condition
is
first
sensed
,
must
be
manually
reset
.
The
target
is
not
a
seal
-
in
type
.
It
The
auxiliary
telephone
-
type
relay
contacts
will
close
and
carry
30
amps
DC
These
momentarily
for
tripping
duty
at
control
voltages
of
250
volts
DC
or
less
,
contacts
will
carry
one
amp
continuously
and
have
an
interrupting
rating
as
shown
in
Table
3
.
TABLE
3
AUXILIARY
TELEPHONE
-
TYPE
RELAY
INTERRUPTING
RATINGS
AMP
INDUCTIVE
AMP
NON
-
INDUCTIVE
110
0.80
2.1
Vol
ts
AC
(
50
/
60
hertz
)
120
0.75
2.0
220
0.55
1.1
240
0.50
1.0
Volts
DC
48
1.0
3.0
110
0.5
1.7
125
0.5
1.5
220
0.28
0.78
250
0.25
0.75
The
IRT
51
G
is
furnished
with
a
target
seal
-
in
unit
and
a
latching
-
type
auxiliary
telephone
relay
.
See
TARGET
SEAL
-
IN
UNIT
RATINGS
,
Table
2
;
and
AUXILIARY
TELEPHONE
TYPE
RELAY
INTERRUPTING
RATINGS
,
Table
3
.
The
auxiliary
circuit
will
operate
whenever
an
overtemperature
condition
is
The
relay
will
not
permit
the
auxiliary
circuit
to
reset
until
the
detected
temperature
decreases
to
below
a
preselected
temperature
level
,
and
the
right
-
hand
(
IRTR
)
contact
has
closed
.
sensed
.
7
Courtesy of NationalSwitchgear.com

GEK
-
86038
The
auxiliary
circuit
may
be
reset
manually
by
pushing
upward
on
the
reset
rod
located
on
the
bottom
left
side
of
the
cover
.
Or
it
may
be
reset
electrically
from
a
remote
location
by
connecting
a
control
switch
across
terminals
19
and
20
.
Or
the
relay
may
be
made
self
-
resetting
by
shorting
terminals
19
and
20
together
.
If
either
the
remote
electrical
or
self
-
resetting
functions
are
selected
,
and
the
relay
is
reset
,
the
target
will
remain
in
view
.
To
remove
the
target
indication
,
the
reset
rod
must
be
pushed
manually
.
The
IRT
51
H
is
similar
to
the
IRT
51
G
.
The
difference
between
these
two
models
is
that
the
IRT
51
H
is
furnished
with
a
three
wire
,
single
element
,
tip
sensitive
,
100
ohms
at
0
OC
,
platinum
RTD
assembly
.
The
RTD
assembly
comes
with
a
special
brass
reducing
fitting
that
will
permit
replacement
of
existing
General
Electric
temperature
relays
,
Type
TBB
,
having
sylphon
bulbs
and
capillaries
,
with
an
IRT
51
H
.
See
Figure
4
,
RTD
Assembly
.
BURDENS
Table
4
shows
the
burdens
for
the
operating
units
of
the
type
IRT
relays
based
upon
the
type
of
RTD
for
which
the
unit
is
designed
.
TABLE
4
OPERATING
UNIT
BURDENS
RTD
DESCRIPTION
OHMS
UC
MATERIAL
VOLTS
*
FREQUENCY
MILLIAMPS
VOLT
-
AMPS
WATTS
2.61
7.62
10
25
63.5
60
120
copper
2.60
31.7
7.61
240
60
2.71
8.77
73.1
120
50
2.71
8.76
36.5
240
50
2.67
7.80
piatinum
65.4
100
0
120
60
2.69
7.87
240
32.8
60
9.04
2.79
75.3
120
50
2.80
37.8
9.07
240
50
2.79
8.17
120
0
nickel
120
60
68.1
2.79
240
34.0
8.16
60
2.91
78.4
9.41
120
50
9.41
2.91
240
50
39.2
The
milliamperes
for
the
110
/
220
volt
operation
are
approximately
92
%
of
the
values
shown
in
approximately
84
%
of
the
values
shown
in
Table
4
.
The
volt
-
amperes
and
watts
are
reduced
to
Table
4
.
Tables
5
,
6
and
7
show
the
burden
data
for
the
auxiliary
circuits
of
the
IRT
relays
.
The
IRT
51
F
,
IRT
51
G
and
IRT
51
H
relays
do
not
have
a
single
burden
,
rather
the
burden
changes
as
the
relay
auxilary
circuit
changes
its
state
from
reset
to
picked
up
.
Tables
6
and
7
reflect
the
transitional
and
steady
state
burdens
of
the
auxiliary
circuits
.
8
Courtesy of NationalSwitchgear.com

GEK
-
86038
TABLE
5
BURDEN
FOR
IRT
51
E
TARGET
SEAL
-
IN
UNIT
TAP
OHMS
0.2
7.0
2.0
0.13
TABLE
6
BURDEN
FOR
IRT
51
F
AUXILIARY
CIRCUIT
STATE
PICKED
UP
NOT
PICKED
UP
(
OHMS
)
VOLTS
FREQUENCY
MOMENTARY
CONTINUOUS
110
50
/
60
50
/
50
50
/
60
50
/
60
780
ohms
850
ohms
3530
ohms
3850
ohms
750
ohms
850
ohms
3850
ohms
3850
ohms
infinite
infinite
infinite
infinite
infinite
infinite
infinite
infinite
2650
ohms
2900
ohms
5400
ohms
5900
ohms
2550
ohms
2900
ohms
5200
ohms
5900
ohms
120
220
240
110
DC
125
DC
220
DC
250
DC
TABLE
7
BURDEN
FOR
IRT
51
G
AND
IRT
51
GH
AUXILIARY
CIRCUIT
TARGET
SEAL
-
IN
UNIT
DURING
VOLTS
FREQ
.
TRANSITION
STEADY
-
STATE
TAP
OHMS
110
50
/
60
50
/
60
50
/
60
50
/
60
1830
ohms
infinite
ohms
2000
ohms
infinite
ohms
3700
ohms
infinite
ohms
4000
ohms
infinite
ohms
1760
ohms
infinite
ohms
2000
ohms
infinite
ohms
3520
ohms
infinite
ohms
4000
ohms
infinite
ohms
0.2
7.0
120
2.0
0.13
220
240
no
DC
125
DC
220
DC
250
DC
CONSTRUCTION
The
relay
case
is
suitable
for
either
surface
or
semi
-
flush
panel
mounting
.
Hardware
is
provided
with
the
relay
for
either
mounting
method
.
The
cover
attaches
to
the
case
with
four
cover
screws
which
have
provisions
for
a
sealing
wire
.
The
cover
also
has
the
reset
mechanism
for
target
reset
.
On
the
IRT
51
G
and
IRT
51
H
,
this
reset
mechanism
is
used
to
manually
reset
the
relay
.
Care
must
be
taken
when
removing
or
replacing
the
cover
on
the
case
because
of
the mechancial interaction
between
the
reset
mechanism
and
the
individual internal
components
of
the
relay
.
Forcing
the
cover
on
or
off
may
damage
the
reset
mechanism
system
.
9
Courtesy of NationalSwitchgear.com

GEK
-
86038
The
back
of
the
case
has
studs
mounted
in
an
outer
block
.
These
studs
are
used
for
making
the
external
wiring
connections
to
the
relay
case
.
A
removable
connection
plug
connects
the
outer
block
to
an
inner
block
which
is
connected
to
the
internal
wiring
of
the
relay
.
Both
the
outer
and
inner
blocks
have
spring
-
backed
contact
fingers
to
assure
good
electrical
contact
with
the
connection
plug
.
The
relay
mechanism
is
mounted
in
a
steel
framework
called
a
cradle
and
is
a
complete
unit
with
all
leads
being
terminated
at
the
inner
block
.
The
cradle
is
held
securely
in
the
case
with
a
latch
at
the
top
and
the
bottom
and
by
a
guide
pin
at
the
back
of
the
case
,
into
the
case
upside
down
,
connections
,
also
locks
the
latch
in
place
,
connection
plug
in
place
.
The
case
and
cradle
design
prevents
inserting
the
relay
The
connection
plug
,
besides
making
electrical
The
cover
,
in
turn
,
holds
the
To
draw
out
the
relay
unit
from
the
case
,
first
carefully
remove
the
cover
,
then
the
connection
plugs
.
Shorting
bars
are
built
into
the
relay
case
to
short
the
current
transformer
circuits
.
Release
the
latches
.
The
relay
unit
may
now
be
removed
from
the
case
by
pulling
on
the
cradle
.
To
replace
the
relay
unit
,
follow
the
reverse
order
.
Use
care
when
placing
the
cover
back
on
to
the
relay
case
to
avoid
damaging
the
reset
mechanism
.
RECEIVING
,
HANDLING
AND
STORAGE
These
relays
,
when
not
included
as
part
of
a
control
panel
,
are
shipped
in
cartons
designed
to
protect
them
against
damage
,
relay
,
examine
it
for
any
damage
sustained
in
transit
,
handling
is
evident
,
file
a
damage
claim
at
once
with
the
transportation
company
and
promptly
notify
the
nearest
General
Electric
Apparatus
Sales
Office
.
Exercise
care
when
handling
or
unpacking
the
relay
,
to
avoid
disturbing
adjustments
or
damaging
the
relay
.
Immediately
upon
receipt
of
a
If
damage
due
to
rough
Perform
an
inspection
and
an
acceptance
test
as
soon
as
the
relay
is
received
to
make
sure
that
no
damage
was
sustained
during
shipment
and
that
the
relay
calibrations
have
not
been
disturbed
.
If
the
relays
are
not
to
be
installed
immediately
,
they
should
be
stored
in
their
original
cartons
in
a
place
that
is
free
from
moisture
,
dust
and
metallic
particles
.
Foreign
matter
collected
on
the
outside
of
the
case
may
find
its
way
to
the
inside
of
the
case
when
the
cover
is
removed
,
creating
the
possiblity
of
relay
misoperation
.
INSTALLATION
The
location
should
be
clean
and
dry
,
free
from
dust
and
vibration
,
and
well
lighted
to
facilitate
inspection
and
testing
.
The
relay
should
be
mounted
on
a
vertical
surface
,
drilling
drawings
are
shown
in
Figures
17
and
18
.
The
outline
and
panel
10
Courtesy of NationalSwitchgear.com