47
MX4777 Rev. D ©2021
B
ENTER
EXIT
OUTSIDE
OBSTRUCTION
LOOP
A
ACCESS CONTROL
DEVICE
(Card reader, etc.)
MINIMUM 6FT FROM
GATE
Vehicle Detectors and Loop Layout for Dual Gate Openings less than 28 feet*
or Single Gate Openings less than 20 feet*
PUBLIC SIDE
This layout illustrates a
bi-directional traffic system with
controlled access entry (card
reader, radio control, etc.) and a
free exit loop. The gate is closed
by a TIMER TO CLOSE. The
timer to close starts when all
loops are clear. The timer is
adjustable from 1 to 99 seconds.
For an exit only system, the
FREE EXIT loop is replaced by
an INSIDE OBSTRUCTION
loop.
FREE EXIT loop is replaced by
an INSIDE OBSTRUCTION
loop
.
SECURE SIDE
C
D
E
F
CENTER
LOOP
FREE EXIT
or
INSIDE
OBSTRUCTION
LOOP
* NOTE: A minimum of three (3) detectors are required for this type of gate.
DIMENSIONS
A = 6 to 20 feet (2 to 6 meters)
B = 6 to 8ft (2m to 243cm)
C = Maintain 4ft (122cm) min.
D = Maintain 5ft (152cm) between
loop and edge of roadway. No vehicle
can pass through such a small area
and escape detection.
E = Maximum 4ft (122cm). Vehicle must be
able to pass from one loop to the next
without loss of detection.
F = The distance from gate to FREE EXIT
LOOP is equal to the gate panel length
plus 4ft (122cm).
APPENDIX A - VEHICLE DETECTOR LOOPS