21
SPEAR™ Single-Phase Recloser System
INSTALLATION AND OPERATION INSTRUCTIONS
MN280048EN June 2016
Grounding the control
The control cabinet must be grounded. A grounding
connector on the underside of the cabinet will
accommodate No. 14 solid through No. 4 stranded
conductors.
Suggested methods for grounding the control and recloser
are shown in Figure 19 and Figure 20.
Figure 19 illustrates grounding methods for 4-wire multi-
grounded systems with local supply voltage transformer.
Figure 20 illustrates grounding methods for 4-wire multi-
grounded systems with remote supply voltage transformer
(within one-pole span).
For effective surge protection, all control and power
conductors for the SPEAR single-phase recloser control
must be routed parallel to a corresponding ground path.
For example, the AC power supply for the control should
be parallel to and equal in length to the transformer ground
path. The control cable should be parallel to and routed
close to the recloser ground path.
Grounding with a local supply voltage transformer;
4-wire multi-grounded
Installation of a SPEAR single-phase recloser control with a
local supply voltage transformer must include the following:
●
●
Protection of the recloser bushings and the supplying
transformer with lightning arresters.
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●
Grounding of the recloser head and tank.
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●
Grounding of the transformer tank.
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●
Grounding of the control cabinet.
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●
Grounding of the SCADA equipment.
IMPORTANT
All external inputs to the SPEAR single-phase recloser
control must be routed within 8 inches of their
corresponding ground. During a surge, a potential of
approximately 1.5 kV per foot can develop in the conductors.
Differences between conductor and ground path lengths
can add additional stress to the control components in the
event of a power surge.
IMPORTANT
In pole-mounted applications, a ground connection must
be made between the recloser, transformer, recloser
control, and SCADA equipment for proper protection of the
equipment. The pole ground must be sized per local utility
practices to minimize the impedance between the recloser
and the control.
Figure 19 .
Surge
Arrester
Recloser
Head Ground
Surge
Arrester
Transformer
Surge
Arrester
Arrester Ground
SPEAR
Recloser
Pole
Supply
Voltage
Pole
Ground
SPEAR
Control
Customer Ground Connection
At External Lug
NEU AC
GND
NEU
AC
Input
Terminal
Block
Control
Cable
AC
NEUTRAL
SPEAR Control
Supply Voltage
Transformer
ELECTRICAL CONNECTIONS
Line to Neutral connected transformer
Input Terminal
Block X1
External
Ground Lug
Surge
Arrester
Recloser
Head Ground
Surge
Arrester
Transformer
Surge
Arrester
Arrester Ground
SPEAR
Recloser
Pole
Supply
Voltage
Pole
Ground
SPEAR
Control
Customer Ground Connection
At External Lug
NEU AC
GND
NEU
AC
Input
Terminal
Block
Control
Cable
AC
NEUTRAL
SPEAR Control
Supply Voltage
Transformer
ELECTRICAL CONNECTIONS
Line to Neutral connected transformer
Input Terminal
Block X1
External
Ground Lug
Recommended grounding method for the
SPEAR single-phase recloser control installed on 4-wire
multi-grounded with local supply voltage transformer
WARNING
Hazardous voltage . Recloser and control must be
solidly grounded . Follow all locally approved procedures
and safety practices when grounding this equipment .
Improper grounding can result in contact with high
voltage, which will cause death or severe personal
injury .
G115 .1
