Lightning Protection And Grounding; Dual-S Installation - Hunter X-Core Owners Manual And Programming Instructions

LighTNiNg proTECTioN AND groUNDiNg

Proper grounding of decoder systems is part of the installation
that requires consideration. Properly grounded decoder systems
perform very well even in high-lightning regions. Poor grounding
often results in unnecessary equipment losses and irrigation
down time.
Earth grounding rules for the I-CORE decoder controllers are
the same as for conventional I-CORE controllers. A large ground
lug is provided for connection of bare copper wire to earth
grounding hardware.
Hunter DUAL-S surge arrestors must be used on all DUAL
two-wire systems. The DUAL-S surge arrestor attaches directly
to the two-wire path to minimize the damage from lightning
strikes. The amount of surge protection needed depends on how
exposed the area is to lightning and on how well the installation
needs to be protected. In addition to grounding the controller,
the minimum recommended level of protection is one DUAL-S
grounded at the end of each two-wire path and one DUAL-S
grounded every 1000 feet/300 m or twelfth decoder. For higher
levels of protection, attach surge arrestors more often.
Similar to the DUAL decoders, the DUAL-S is sealed from
moisture and should be placed in its own valve box. It is
important that both the controller and the surge arrestors are
grounded to ground rods or plates with less than 10 ohms
resistance. Use grounding electrodes that are UL listed or meet
the minimum requirements of the National Electrical Code (NEC)
as well as local codes. At minimum, the grounding circuit for
controllers will include a copper clad steel ground rod, or copper
ground plate.
Copper ground rods should have a minimum diameter of
⁄ "/1.5 cm and a minimum length of 8 feet/2.5 m. These are to
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be driven into the ground at a location 8 to 10 feet/2.4 to 3 m
from the equipment or wires connected to it, at right angles to
the two-wire path.. Install all grounding circuit components in
straight lines. When it is necessary to make bends, do not make
sharp turns.
Copper grounding plate assemblies intended for grounding
applications have minimum dimensions of 4" x 36" x 0.0625"
(100 mm x 2.4 m x 1.58 mm). A 25-foot (8 m) continuous length
(no splices allowed unless using exothermic welding process) of 6
AWG solid bare copper wire is to be attached to the plate using
an approved welding process.
The earth-to-ground resistance measured should be no more
than 10 ohms. If the resistance is more than 10 ohms, then
additional ground plates and PowerSet
required that the soil surrounding copper electrodes be kept at a
minimum moisture level of 15 percent at all times by dedicating
an irrigation station at each controller location.

DUAL-s installation

DUAL-S surge arrestors should be installed at the end of every
two-wire path and at intervals of 1000 feet/300 m or every
twelfth decoder.
can be installed. It is
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