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lnstallation and
Adjustments lnstructions
Long Time
DelaY
Thelonqtimedelaysetsthetrippingdelayo{thetriounrtbased
on the
magnitude
of
ti'te'ove'i:u're"nt
condition
The setting of
the long time delay
t"r""it
on"
oflive
detay
bands
The delay
bands
are inverse
r
t
tu'it'[
i'ntiiont
The
lit delay provides
a
selective long time
p'ot"Jtion
brecause
the delay
is inversely
orooortional
to
the
squaiJoitf-te magnitude
of
the
overcurrent
:f".iiiii,"
iHl;
;;r.i
tnJtiigt.tlt
ov"ercurrent
conditions
have
shorter
delays and, conJers6ly'
lo*"t
overcurrent
conditions
have longer
delays
rn"jo*& uul'"t
of
the
selected
band
def ine
the
minimum
o"r"!
i"iiit"
initiation
of
lhe 9ircull9.r.?:|<,:
il
+i
[i
.,j
"r
n
" yn"*:
:l;'"
ii
[:
fr' ::,
fl"J]
T
J[:
ffi
:["'fi
m?[i
:[ffi;
H%
?..
J'
;;'IJ;
i
""s
t',
"
rr'
"
i
o*e
r
-va
t
u
e
or
the long time delav
ouni
illlt"'"nJed
to 3
5
6'
1O
17' or
30
seconds at
a
current
"oll".ponJing
to
6 times
the
long time
cpttino
Chanqinq
tn" f"ong"i-"-t"iting
changes the
current
i,i
-ilY;Hir.
"
ii*""oit
ivt
aie
rere
re
nced
IIiJHJ
il?#?JXn
,,re
raurt
protection.is a' rhermar Memorv"
f
unction. The
purpose
oiit-'"
If rt"*al
Memory function
is
to
;l;;;i
;d;;&,
Flit'tt"nilntermittent
overcrrrent
condition
rhe
[unction
mav be
,"t'i'i"JLv
placlig
ll:
]!:rmal
Memorv
"ilt;;
"#ih;
ittnrot
the
trip
unit
to
the
ln'
position
With the
function actlvated'
the long
time
delay
counter
does
not immediately reset
t")"i"
*n"nih"
currentfalls
below the
i#n'
iil;
ilrirp
uur'"lJntt"'o'
lt
counts down
at a
rate
determined
by tne
magnit'O"Glt't"
remaining
current
When
there
is a
persistent
i"i"t'it"ti
overcurrent
that does
not
i"#,i,"
.[;ritime
picXuo level,
the
delay
counts
are
accu-
mulated. Tripping
o""'it
;'["nit't"'"""nulatedvalue
reaches
the selected long
time;;i';
ln1rt" tp""iul,case
where
the
current drops to
n"u'ry
#Iihe
tong
time delay counter does
reset
to
zero.
Thermal Memory protects against
persistant
intermittant
overcurrents.
Short Time Fault
Protection * ,
u* ,*
s
x
x
s&
Current in
MultiPles of
Long Time Setting
1
10
o
E
1oo
o
o
o
a
.;
Elt
'l=
delav
band
f-
t
i
z-sdiono
Example
-
Long Time
DelaY
Bands
I
Long Time
DelaY
Settlng
L ffi
Overcurrent lntervals
' ff
P61r"3'Cure'l
lnlervals
]
I I
count
'
oo*''
t'l
,/
$hcri
Time
:),:.,r
Dt;,ir,v
i-,1,^r,U
i
i
11
t't
e8
I
1:l
r
l,'f
Setlrnq
W
-':
,)
rf
l,!-i
riu
12
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