OVERVIEW
The fail safe plug-in loop detector allows the gate to stay open when
vehicles are obstructing the gate path. The loop can be set to function as
a Shadow Loop, an Interrupt Loop, or an Exit Loop.
For use with the following gate operator models: LA400PKGU,
LA412PKGU, LA500PKGU, CSL24V, CSL24U, CSW24V, CSW24U,
RSL12U, RSW12U, SL585101U, SL585103U, SL585105U, SL585151U,
SL585501U, SL585503U, SL585505U, SL595101U, SL595103U,
SL595105U, SL595151U, SL595203U, SL595205U, SL3000101U,
SL3000501U, CSW200101U, CSW200501U, HCTDCU.
SHADOW LOOP: Positioned in the path of a swing gate and is active
ONLY when the gate is in the open position. Only used in swing gate
applications.
Plug-in Loop Detector
MODEL LOOPDETLM
To prevent DAMAGE to circuit board, loop detectors and/or the gate
operator, installation MUST be performed by a trained gate systems
technician.
Shadow Loop
Interrupt Loop
INTERRUPT LOOP: Positioned outside the property and when activated
will open a closing gate.
Exit Loop
(Inside Property)
EXIT LOOP: Positioned inside the property and when activated will open a
closed gate.
INSTALLATION
The loop itself must be a continuous length of wire without any breaks or splices. The loop wire can be 14, 16, or 18 gauge stranded wire with either a
cross-linked polyethylene (XLPE) or polyester insulation.
1. Mark the loop layout on the pavement. Remove sharp inside corners
that can damage the loop wire insulation.
2. Determine the thickness of the pavement to ensure that the depth of
the cut will not exceed the thickness of the pavement before
attempting to cut the loop slots. Set the saw to cut a depth (typically
2-2.5 inches [5.1-6.4 cm]) that will ensure a minimum of 1 inch
(2.5 cm) from the top of the loop wires to the pavement surface. The
saw width must be larger than the diameter of the loop wire to avoid
damage to the wire insulation when placed in the saw cut. Cut the
loop, corner angles, and feeder slots. Remove all debris from the
saw slot with compressed air. Check that the bottom of the cut is
smooth and did not break though the thickness of the pavement.
3. Wrap the loop wire in the loop slot using a wooden stick or roller to
insert the wire to the bottom of the saw slot until the desired
number of turns are reached (Caution: do not use a sharp object).
Each turn of wire must lay flat on top of the previous turn.
LOOP PERIMETER NUMBER OF TURNS
10-13 feet (3-4 m) 4
14-26 feet (4.3-7.9 m) 3
27-80 feet (8.2-24.4 m) 2
81 feet (24.7 m) and up 1
4. The wire must be twisted a minimum of 6 turns per foot from the
end of the feeder slot to the expansion board to minimize noise or
interference. If a splice is required in the feeder cable, solder each
splice and protect with a moisture proof seal.
5. Apply the sealant. The sealant selected should have good adhering
properties with similar contraction and expansion characteristics as
the pavement material.
Loops MUST BE 4 feet (1.2 m) away from each other.
Remove sharp inside corners.
1/8" to 1/4" (3.2 to 6.4 mm)
Saw Slot
NOTE: Ensure the saw cut is
wide enough to allow the
Road Surface
Sealant
sealant to flow around the loop
wires.
Minimum of 1 inch
(2.5 cm)
Loop Wire
(3 wires shown)
1/8" to 1/4"
(3.2 to 6.4
mm) Saw
Slot
Feeder Slot
End of Saw Cut
1
WIRING
1. Plug the loop detector into the desired slot (Shadow, Interrupt, or Exit)
on the expansion board of the operator. NOTE: If only LOOPDETLM
loop detectors are used, manual frequency adjustments are not
required and crosstalk is eliminated. If a LOOPDETLM is used in
combination with other alternate loop detectors, then manual
frequency adjustments may be required.
2. Insert the twisted wires from the loop into the corresponding terminal
(Shadow, Interrupt, or Exit) on the expansion board of the operator.
Polarity does not matter.
OPERATION
BLUE LED WHITE LED EXPLANATION
1 Blink (every
10 seconds)
2 Blinks Rapid Blinks (active
3 Blinks Rapid Blinks (active
4 Blinks Rapid Blinks (active
OFF 2 Blinks Successful Reset
OFF Slow Blinks Loop detector is in TEST mode
Solid Solid Active Loop
DIAL
SETTINGS
TEST Mode Used to test the loop detector
1-8 Determines the sensitivity setting for the loop detector:
PROG Mode Used to change the frequency and track out options of
FREQUENCY
To change the frequency of the loop detector:
1. Turn the dial to PROG.
2. The blue LED will show the current frequency setting.
3. Press and release the frequency button to cycle through the 4
frequency settings.
To reset frequency to factory default, hold the frequency button for 5
seconds.
CALL TRACK OUT
To change the amount of time the loop will stay active:
1. Turn dial to PROG.
2. The white LEDs will show the current track out setting:
• Top and Bottom LEDs ON- infinite (DEFAULT)
• Top LED ON- fast (5 minutes)
• Bottom LED ON- slow (15 minutes)
3. Toggle the boost switch to cycle through the track out settings.
BOOST SWITCH
The boost switch will increase the sensitivity of the loop detector to
detect high profile vehicles (such as semi trucks).
White LEDs
(located under dial)
OFF Normal Operation
Open Loop (see
fault) or OFF
TROUBLESHOOTING)
Shorted Loop (see
fault) or OFF
TROUBLESHOOTING)
Failed Authentication (see
fault)
TROUBLESHOOTING)
EXPLANATION
1 is the lowest sensitivity (large vehicle) setting and 8
is the highest sensitivity (small vehicle). Default
setting is 4.
the loop detector
Exit Loop
Exit Slot
POWER
BOARD
TO MAIN
EYE
1
ONLY
EYE/
2
EDGE
EYE/
3
EDGE
COM
OPEN
CLOSE
SBC
OPN
CLS
STP
COM
Shadow Slot
Shadow Loop EXPANSION BOARD
Interrupt Slot
Interrupt Loop
TROUBLESHOOTING
Open or Shorted Loop (2 and 3 Blink errors):
Test the loop detector (refer to TEST THE LOOP DETECTOR section). If
the loop detector passes the test, this indicates the loop detector is
working properly and there is an issue with the loop wiring.
Failed Authentication (4 Blink error):
• Check the wire connecting the expansion board to the main board or
• Unplug the loop detector then plug it back into the same slot (clears
all faults and keeps the current frequency settings, authenticates) or
• Unplug the loop detector. Then unplug the J15 plug on the operator’s
control board and plug it back in after 2-3 seconds. This allows the
loop detector to be plugged into a different slot (clears all faults and
keeps the current frequency settings, authenticates).
To clear a fault:
• Press the reset button on the operator (clears all faults) or
• Unplug the loop detector then plug it back into the same slot.
The loop is making false detections:
• There is crosstalk between the LOOPDETLM and the alternate loop
detector or
• Change the frequency or lower the sensitivity setting of the loop
detector.
The loop will not activate when a vehicle passes over it:
• Turn the boost switch ON or increase the sensitivity of the loop
detector or
• If the blue and white LEDs are solid, indicating an Active Loop, and the
operator does not activate, there could be a fault. Once the loop is
inactive, check the LED codes for a fault (refer to LED table).
TEST THE LOOP DETECTOR
1. Turn the dial to TEST. The loop detector will send a signal to the main
board simulating a vehicle over the loop.
Exit: If the gate is closed, it will open or if the gate is already open it
will remain open.
Shadow: Active ONLY when the gate is in the open position. If the gate
is open, it will remain open.
Interrupt: If the gate is closing, it will open.
2. Turn the dial back to the desired sensitivity setting.
WARRANTY
ONE YEAR LIMITED WARRANTY
LiftMaster warrants to the first consumer purchaser of this product that
is free from defect in materials and/or workmanship for a period of 1 year
from the date of purchase.
THIS DEVICE COMPLIES WITH PART 15 OF THE FCC RULES. OPERATION IS SUBJECT TO
THE FOLLOWING TWO CONDITIONS: (1) THIS DEVICE MAY NOT CAUSE HARMFUL
INTERFERENCE, AND (2) THIS DEVICE MUST ACCEPT ANY INTERFERENCE RECEIVED,
INCLUDING INTERFERENCE THAT MAY CAUSE UNDESIRED OPERATION.
This Class B digital apparatus complies with Canadian ICES-003.
Cet appareil numérique de la classe B est conforme à la norme NMB-003 du Canada.
Frequency Button
Blue LED
(located under dial)
Boost Switch
Dial
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