6
Loop Installation Tips
The loop consists of a 12 to 18 gauge stranded wire
suitable for direct burial with low AC and DC resis-
tance. The size of your loop will be determined by the
width of the area in which you need detection, and the
height of the vehicles you need to detect. If high-bed
trucks will be detected, the loop should be no less than
6’ on a side (i.e. at least 6’×6’.)
Smaller loops are suitable for car or fork truck detec-
tion. The depth of the saw cut is typically 1¼” to 2”,
and from ¼” to 3/8” wide. Cut the corners of the loop
to 45° angles to avoid pulling loop wires around a 90°
corner and risk damaging the wires. Do no push the
loop wires into the saw-cut with a sharp object. Be
sure to keep the loops a minimum of 2” above any
rebar or wire mesh installed in the roadway.
The loop wire is wound to form a coil (usually 3 to 5
turns.) Ideally, there should be no splices in the loop.
Or, in other words, attach your loop wire to the gray
wire in the wiring harness, run the loop out to your
saw-cut, go around the saw cut the recommended
number of times, return the loop wire back to the de-
tector. Twist the lead-in portion of the loop wires at
least 5 to 7 twists per foot, and then connect the other
end of the loop wire to the brown wire on the wiring
harness. The lead-ins and loop should be made of one
continuous piece of wire.
Important:
Twist only the lead-in (the part of the loop
wire that runs from the edge of the loop back to the
detector.)
Do not twist the wires in the loops themselves.
