CLAS AC 5028, Manual, Page: 6 / 12

INTRODUCTION
DESCRIPTION
APPLICATIONS
AC 5028
ELECTRONIC STETHOSCOPE LEAK DETECTOR
Moving parts, liquids and gases cause turbulence or friction.
This turbulence or friction can then produces high frequency ultrasonic waves whose frequencies are normally
higher than 20kHz and are far above the range of human hearing. The ultrasonic waves can travel in air and their
intensity will attenuate rapidly as their propagation distance increases.
Ultrasonic waves are highly directional, this directional aspect of ultrasonic waves allows one to isolate a suspect
signature sound from other background noises and detect its exact location.
This tool operates on the principle mentioned above, it uses advanced ultrasonic sensing technology and converts
inaudible ultrasonic sound into an audible sound which bears a close likeness to the natural incoming sample; for
example, a gas leak sounds like a "hiss" and a defective bearing sounds like a "clicking or chatter".
Since this tool is tuned to listen to the ultrasonic range, it is unaffected by everyday sounds such as wind, voices,
and traffi c.
This AC 5028 is easy to carry and operate, and its detection result is accurate and reliable. It is very useful in
preventive maintenance, trouble shooting, quality control and diagnostics in the automotive, industrial,
manufacturing and process industries.
This tool is a very useful diagnostic test tool which can reduce downtime and maintenance related costs of the tested
equipments. Through the detection of ultrasonic sound, this tool can be used to inspect and check such items as
ignition systems, vacuum problems, air brake systems, bearings, gear trains, cam and tappet assemblies, internal
combustion engine valving and piston blow-by, gaseous piping and ducting, seals in refrigerated van bodies, air
ducts, hydraulic systems, Freon leaks, and many other components.
This tool consists of an ultrasound receiver, a tone generator, an air probe, a contact probe and a headphone.
The receiver is sensitive only to ultrasonic energy in the frequency range of 36000 to 44000Hz. The energy is
amplifi ed by internal circuitry and converted to audible sounds (available through the headphone) and an intensity
reading on the red LED display.
The tone generator is used with the ultrasound receiver to check for faulty seals in nonpressurized enclosures, such
as automotive cabin windows/doors/roofs, etc.
AC 5028 can be used to effi ciently investigate the fi ve major areas of repair and preventive maintenance in the
automotive, industrial, and etc.
1. Air/Vacuum Leaks
Both vacuum and compressed air leaks from a hole down to 0.127mm create an energy packet or wave front,
which can result in an ultrasonic emission with a differential of 1 psi.
2. Gas and Liquid Turbulence
Turbulence associated with steam trap and internal valve leaks, cavitation, and blockages in liquid and air/gas
lines.