ATSI LF-22 Посібник з експлуатації

Переглянути онлайн або завантажити pdf Посібник з експлуатації для Вимірювальні прилади ATSI LF-22. ATSI LF-22 2 сторінки. Loop finder

LF-22 Loop Finder - Operating Guide

Version 2 – 5/15/15

WARNING: The procedure for finding existing loops with the LF-22 describes walking around in the street

while looking at the tester. THE USER MUST TAKE ADEQUATE PRECAUTIONS TO PREVENT INJURY

FROM MOTORISTS (LIKE ESTABLISHING A WORKZONE, AND DIVERTING TRAFFIC). Do not take

chances with the "Superman" method, which is thinking you are clever enough and quick enough to stay out

of the way of traffic while intently watching the Loop Finder for signal strength readings! Be smart. Avoid

injury. Do the right thing. Establish a Work Zone and then do your work.

Thank you for purchasing the ATSI LF-22 Loop Finder. We hope this handy tool will help you maintain your

agency's vehicle detection loop installations.

The LF-22 is designed to sense electromagnetic fields (EMF) and give a field

flux strength indication by lighting up a curved string of LED's on the face of the

unit. The intended purpose is to allow traffic signal technicians to find the

electromagnetic field that is emitted by inductive loop wires that are being

excited by a working vehicle loop detector. With a little practice, the LF-22

operator can locate the approximate position of the loop wires that are installed

beneath the road surface.

The LF-22 gives a visual indication of the strength of the EMF that allows the

technician to identify and diagnose loop detection installations that fail to detect

high-bed truck trailers (for vehicle counting and classifying) or small vehicles

with low electromagnetic "footprints" (motorcycles and bicycles). The service

technician can also use the LF-22 to locate and mark loops that have been covered up by re-surfacing work.

This is helpful when nearby road repairs or utility work could destroy the loop if the equipment operators are

not aware of the location of the loop wires.

Twisted lead-in wires running between the junction box and the actual

loop emit a much weaker signal, and are much harder to detect.

Lead-in wires in the road surface are generally 5 inches or less below

the surface, and can usually be detected by the LF-22. Twisted

"Home Run" wiring, which connects the loop wires in the junction box

to the signal cabinet, are typically 12 to 24 inches below the surface,

sometimes run within a shield or metallic conduit, and usually cannot

be detected by the LF-22.

To use the LF-22, slide the left-most slide switch to the "ON" position,

and observe the signal strength and power on LEDs on the front of the

unit. All the LEDs should light up briefly, and the power on LED

should remain lit. The antenna in the LF-22 is most sensitive to EMF

lines of flux that pass through the unit perpendicular to the front panel,

so the instructions given here work when the unit is held horizontally,

or "flat" with respect to the ground, as show here. Start with the two

sensitivity switches in the up position to maximize the sensitivity, and

hold the unit "flat" to the ground at waist level and walk over the area

you want to survey, while watching the LEDs on the face of the LF-22.

You will begin to detect loop wires of the working loops.