3
STEP 2:
CONNECTING THE WIRING
How to choose the ri
ght type of sprinkler wire:
Use 18-gauge “bell,”
“thermostat” or “underground burial” wire for the sprinkling system. “
Bell wire
”
is available in single strands or twisted in 2 or 3 wire sets and can only be
used indoors. “
Thermostat wire
,” the most common sprinkling system wire, is
typically available with up to 7 wires twisted inside a brown PVC jacket (about
¼” in diameter), and is suitable for most indoor and conduit installations.
“Direct Burial”
cable is similar to thermostat wire, except the jacket is made of
a black Poly UV resistant material, and is suitable for any indoor or outdoor
installation, including sunlight exposure. Each individual wire is color-coded.
Note:
Some areas require by code the use of UL approved cable only. Most
Direct Burial Cables have this approval. Most thermostat and bell wires do not.
Important:
18 gauge wire or /larger is recommended for sprinkler system wire,
allowing cable to be run up to 600’ without problems. Some thermostat wire
that is referred to as “sprinkler wire” may actually be a smaller gauge (#19 or
#20) and will not have the UL listing or the capacity to run long distances.
The number of wires needed is determined by the number of valves being
wired, plus a common wire. For example, three valves in a grouping require a
4-wire cable since the 4th wire serves as the common wire. If a system had
two valves in the front yard, and four in the back, the wiring could be run in
one of two ways:
1) Use a single run or 18/7 (18 gauge, 7 wires) cable connected ‘in-series’
from the front valves to the back valves to the timer;
2) Use one run of 18/3 cable from the timer to the front valves, and one run of
18/5 cable from the timer to the back valves.
All wiring connections should be sealed with a water-tight connector. Cables
that are run indoors should be properly secured with a staple or clip.
How to connect the valves:
Each valve connects to the timer through two
wires. One wire from each valve solenoid must connect to the output terminal
of the timer. This is the “HOT” connection. The second wire of each solenoid
must connect to the (COM.) common terminal of the timer. This is the
“COMMON” connection. If the valves are grouped together, it is easier to join
the common from all valves and just run one wire to the timer’s (COM.) com-
mon terminal.
Note:
Only one valve may be connected to each station output terminal.