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G R I D S H I E L D
8.3 Arrester protection
Surge arresters must be installed on both the
source and load sides of the recloser. It is advisable
to connect the arrester grounds to the recloser
ground and extend them to the pole ground.
To minimize stray inductance and maximize the
effectiveness of the arresters, it is recommended
to keep the leads connecting to the arresters
as short as possible.
8.4 Control power
The control power is supplied according to the
typical wiring diagram provided in appendix A.
Caution should be exercised when connecting
the hot and neutral to the desired source.
If 240 V AC is used, the GFI receptacle should
be labeled accordingly.
If the control comes with a 2-, 3-, 5- or 8-pin power
connector and power cable, connect the AC source
to this cable. If not, you can use one of the
knockouts or drill the removable plate to
accommodate a conduit.
For three-phase voltage wiring, you can connect
from the recloser to the low voltage control cabinet
terminal block and then to the voltage inputs
on the back of the relay for metering and voltage-
dependent protection. When the control cabinet
has a 5- or 8-pin power connector, the connections
go through an AC transfer switch first. Otherwise,
wire the three voltage transformers (VTs) directly
to the terminal block in the control cabinet. There's
no need to wire any voltage inputs directly to the
back of the relay.
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3 P/ 3 S P R E C L O S E R
If you have optional voltage sensing cables from
external sensors, they can also provide voltage
inputs to the back of the relay.
If you want to obtain control power from one
of the three VTs used for metering, you need to
add jumpers to the control cabinet distribution
terminal block to connect one of the voltage
sources to the control power input. Follow the unit-
specific wiring diagram and add a connection from
the incoming voltage terminal block to the control
power inputs in the control cabinet. Make sure all
terminal block connections are properly tightened.
For detailed information on the overall control
circuit, always refer to the specific wiring diagrams
provided with the recloser.
8.5 Line connections
The recloser is connected in series with the power
line and can operate in either direction. However,
there are three important considerations:
1.
The voltage transformer used to supply
power should be installed on the source side
of the recloser. This ensures that the battery
backup system is not unnecessarily drained
when the circuit is open at the recloser.
2.
When voltage transformers are used for
metering and protection purposes, they
should be installed on the source side.
Additionally, the top terminal of the poles
must be connected to the source side. This is
necessary to accurately measure power flow
and allow the directional protection elements
to function according to the programmed
settings.
3.
The relay settings can be adjusted to change
the CT polarity and phase orientation.
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