Loop Installation And Number Of Wire Turns - Chamberlain ELITE R900 Instruction Manual

L O O P I N S T A L L A T I O N A N D N U M B E R O F W I R E T U R N S
Loop Installation "Saw Cut" Type
1
Mark the loop layout on the pavement. Remove sharp inside corners that can damage the loop wire
insulation.
2
Set the saw to cut to a depth (typically 2" to 2.5") that insures a minimum of 1" from the top of the wire to
pavement surface. The saw cut width should be larger than the wire diameter to avoid damage to the wire
insulation when placed in the saw slot. Cut the loop and feeder slots. Remove all debris from the slot with
compressed air. Check that the bottom of the slot is even.
3
It is highly recommended that a continuous length of wire be used to form the loop and feeder to the
detector. It is also highly recommend using 12-18 AWG cross-link polyethylene (XLPE) insulation for the
loop wire. Use heavier wire gauge for a more durable loop area. Use a wood stick or roller to insert the wire
to the bottom of the saw cut (Do not use sharp objects). Wrap the wire in the loop saw cut until the desired
number of turns is reached. Each turn of wire must lay flat on top of the previous turn.
4
The wire must be twisted together a minimum of 6 twists per foot from the end of the saw cut to the
detector.
5
The wire must be held firmly in the slot with 1" pieces of backer rod every 1 to 2 feet. This prevents the wire
from floating when the loop sealant is applied.
6
Apply the sealant. The sealant selected should have good adhering properties with similar expansion and
contraction characteristics to that of the pavement material.
Number of Wire Turns Needed for Loop
Important
Loop Perimeter
10 feet to 13 feet
14 feet to 26 feet
27 feet to 80 feet
80 feet and up
The wire must be twisted together 6 twists per foot
from the end of the saw cut to the loop detector.
Home Run
6 Road Surface
6 Sealant
5
Backer Rod
Insulated Loop Wire
3 turns Shown, amount varies.
Refer to table
Number of Wire Turns
4
3
2
1
Feeder Slot
30
3
The wire is continuously wound
in the loop saw cut for the
required number of turns. One
turn shown. (Refer to table)
1 Remove sharp inside corners
by making corner cuts
1/8" to 1/4" Width,
2
2" to 2.5" Depth Saw Cut
5
Recommended Loop Wire
XLPE 12-18 gauge
(Use heavier wire gauge for a
more durable loop area)
2 Saw Cut