Issue 2: 2016
OPERATION
If at any point while taking readings a low battery
symbol is displayed at the top right of the display, this
is an indication that the batteries need to be changed
within the next 10 hours of operation. If the batteries
are not changed the AUDIT 207 will stop functioning
at a pre-set voltage and the display will blank, the
instrument will remain in calibration throughout shut
down.
It is good practice to carry out transducer to gauge
ZERO
calibration check after batteries are fitted, see
section 4.2
When switching off, the gauge retains all of its settings.
5.2 Effect of Surface and Hot Conditions
A rough front surface may affect the coupling of sound
between the probe and the work piece. A rough rear
surface will possibly scatter the measuring beam rather
than reflect it. In consequence, rough surfaces tend to
reduce the reflected signals required for measurement.
Observe the Stability indicator as to the strength of the
received signals.
Hot temperatures above 100°C the change in sound-
velocity of the material being measured starts to have a
noticeable effect upon the accuracy of ultrasonic
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Issue 2: 2016
PREPARATION
4.7 Fit Batteries
Locate battery compartment cover and
ZERO
calibration
cap at top of gauge and unscrew cap.
Referring to battery polarity instructions on rear panel of
gauge, Negative to top cap, insert batteries into gauge
ensuring correct polarity.
Replace battery compartment cover cap.
4.8 Other Indications During Use
Low Battery warning Symbol Top right of Display.
First appearance indicates that there are approximately
10 Hours of continuous battery life left.
Audit 207 retains all of its settings after switch off.
4.9 Limitations
With all types of Ultrasonic Thickness Gauges, the
ability to obtain thickness readings is dependent on the
capability of the transmitted signal to penetrate
completely through and return from the rear surface of
the material under test, it is possible due to the
composition and or grain structure, of some materials
plastics, cast iron etc that limitations to the thickness
range is possible, as the material is too
attenuative
for
the ultrasound to penetrate.
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Issue 2: 2016
PREPARATION
3. Press ZERO key.
4. Place the probe on the thinner known thickness of
the test part. followed by the
CAL
key (
2
nd
thickness display
)
is indicated, using up down keys
set this thickness press
CAL
key. Velocity will
automatically enter measurement screen. The Audit
207 is now ready to take readings.
4.5 Metric - Imperial Mode change
For Mode change Press
UNIT
key, you have the
capability to display
mm
or
in
6.0mm single decimal
point or a second press of
UNIT
key operation to display
6.00mm high
resolution, additional repeated presses of the
UNIT
key
changes calibration from
mm
to
in
. low or high
resolution.
4.6 Scan Mode
SCAN
Identifies the minimum thickness measurement
obtained whilst the probe is in scanning contact with the
material being measured as displayed at the top of the
display with live measurements displayed in the centre
section, the gauge memorises the lowest measurement it
finds.
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Issue 2: 2016
PREPARATION
AUDIT 207 can tolerate large changes in signal
strength, but ultimately, under very poor conditions,
insufficient signal will be received to make a
measurement as displayed by the stability indicator for
strength of signals.
5. OPERATION AND APPLICATION INFORMATION
5.1 Basic Technique
The surface of the work piece to be measured should
be cleaned to remove all fouling and other
contamination. Surfaces do not have to be entirely flat
or smooth, but in general the poorer the surface the
less satisfactory it will be for accurate measurements.
Prepare AUDIT 207 for use (as previously described).
Apply a liberal amount of couplant to the work piece at
the point to be measured. lightly press the transducer
squarely against the surface and read the thickness
value from the digital display. The reading will remain
on the display for 5 minutes after the probe is removed
from the work piece.
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