Weathermatic SLFSI-T10 Design Manual page 3

conventionally wired system, a single valve failure can take hours to troubleshoot because the
technician must trace the entire length of the wire to find the defect.
•
Less Wire Means Fewer Problems - Exposure to shovels, rodents, and even lightning is
minimized with two-wire paths because there is less wire in the ground.
•
Extend System in Phases - Irrigation systems can be easily expanded or subdivided after the
original installation without running spare wires, or retrofitting new wiring back to the
controller. On a two-wire system expansion can take place by simply spicing into the end of a
two-wire path and continuing the wire to the new phase of a project.
•
Decoders can be positioned anywhere along the two-wire path – Positioning, adding or moving
decoders and valves is easy because they can be positioned anywhere along the two-wire path
during construction or after.
•
Better Water Management – Adding, splitting, or moving zones makes it easier to hydrozone
plant material and/or modify planting plans in the field after the original design is completed.
•
Reduced Electrical Cost – Two-wire systems are more efficient at power consumption. Because a
two-wire controller actuates the valve hundreds of times a second, the decoder doesn't actually
operate for the full run time thus consuming less electricity. This is especially important for solar
two-wire systems where power consumption is a critical issue.
•
Valves Last Longer – The cyclical nature of two-wire power use to the valve leads to longer valve
lifespan. Because a two-wire controller actuates the valve hundreds of times a second, the
solenoid on the valve doesn't actually operate for the full run time thus extending the life of the
solenoid.
•
Resists Lightning – Since a two-wire system has less wire in the ground, it tends to be less
susceptible to lightning damage vs a conventionally wired system if the decoders are installed in
protected clusters. Proper grounding and wire splicing is critical to ensuring a two-wire system is
more resistant to the effects of lightning.
•
Two Wire Decoder Systems can be Less Expensive than Conventional Wire Systems – Larger
station count two-wire systems are less impacted by high wire costs than conventional systems.
The primary driver in this is the cost of copper and its influence on irrigation wire prices.
EXAMPLE
48 station controller
1 1/2" Valve
Decoder
Wire
TOTAL
3 | P a g e
Conventional Systems
$660
$3,240
N/A
$6,774
$10,672
Two-Wire Systems
$590
$3,240
$3,619
$1,166
$8,614