Rain Bird IC System, Руководство по конструкции, Страница: 17 / 21

IC System
TM
Design Guide, v2.3 17
MAXI
TM
Surge Protectors (MSP-1) on each wire path with MAXI Ground Plates (MGP-1) as
required in the system
4. Although not required, an optional shielding wire can also be utilized to improve the grounding
of the system. If used, the shielding wire should be a 10 AWG (6 mm
2
) bare copper wire that
connects to each of the grounding rods or plates in the system. The purpose of the shielding
wire is to provide shielding for the MAXI wire path by attracting surges to the shielding wire. It
also can reduce the overall earth ground resistance of the system by connecting the ground rods
together. Rain Bird believes the decision to use a shielding wire on a project should be based on
the localized conditions at the project and is not specific to a control system type or
manufacturer type. A course would have a shielding wire regardless of control system, or it does
not. It should be the decision of the irrigation designer.
5. If a shielding wire is used, the ground rods or plates should be tested independently, prior to
connecting the shielding wire to the rods or plates. This will ensure that the rods or plates
provide a good earth ground at the ICSD. A measurement with the shield connected does not
give a true reading of the individual ground location at the ICSD and will give a reading that is
considerably lower than the actual grounding at that location.
6. The primary objective of grounding is to achieve the desired earth ground reading for the rods
or plates regardless of which method is used. Rain Bird has had good success with ground rods
when soil conditions allow them to be driven completely into the soil profile. An 8 foot (2.4 m)
rod will help distribute a surge into lower layers of the soil profile, away from the soil surface
and equipment.
7. ICSDs should be located at dead ends on long wire runs, approaching 500 feet (150m.) Short
wire runs do not require ICSDs at the dead ends. In particular, herringbone pipe layouts do not
require ICSDs at the end of each herringbone lateral.
Types of Pipe Networks
The IC System
TM
works equally well with “herringbone” or “sub-loop lateral” pipe network designs. Rain
Bird looks to the irrigation designer to select the best pipe network layout for the irrigation system
design and then apply the IC System wire path on that layout. Each type of pipe network design offers
different advantages depending upon the location and size of the irrigation system. There is no
preference for the IC System wire path.