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The following settings are possible:
• 16 threshold current values (Io>)
0.100
0.150
0.200
0.250
0.350
0.400
0.450
0.500
0.600
0.650
0.700
0.750
0.850
0.900
0.950
1
OFF
(1) The unit guarantees no entry in the threshold for
currents under 1.05 x Io> set and guarantees entry in
the threshold for currents higher than 1.30 x Io> set.
Selection of type of Io> curve
Four different time-current relationships can be
selected.
Fixed time curve ( = 2)
For protection with fixed time (DT), the trip time is
given by the following relationship.
to> = K x
Definite time curve
For protection with definite time, the relationship
between trip time and overcurrent is given by the
following formula.
to> = K
x
Io>
Caption
to> trip time
k
parameter set by the user to select the trip curve
pair of parameters, depending on the type of
protection selectable
I
earth fault current
Io> trip threshold selectable by the user.
Parameters
values according to the curve selected.
(1)
• Normal inverse time curve (NI):
• Very inverse time curve (VI):
• Extremely inverse time curve (EI):
x In
Selection of to> trip time
The trip time of the protection is adjusted by using
the Dip Switches as shown in the figure.
By means of the Dip Switches, the value of K is set
which, when replaced in the previous relation-
ships, determines trip time to>.
The following settings are possible:
• 16 trip times (to>),
(K = 0.1...1.6 with steps of 0.1)
0.1
0.6
1.1
I
– 1
and
can take on the following
= 0.02
= 0.14.
= 1
= 13.5.
= 2
= 80.
0.2
0.3
0.4
0.7
0.8
0.9
1.2
1.3
1.4
1
2
3
4
0.5
1.0
1.5
1.6
4
Caption
1 Dip Switch for setting
the trip threshold of
protection Io>
2 Dip Switch for setting
timing K of protection
Io>
3 Dip Switch for selecting
the type of curve for
protection Io>:
• DT curve with
definite time
• NI curve with normal
inverse time
• VI curve with very
inverse time
• EI curve with
extremely inverse
time.
4 Dip Switch for selection
of type of toroid for
earth fault (internal/
external)
17
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