NDT Systems Nova 950 Series Operating Manual Download Page 9

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Nova Eclipse TG950 - Users Manual

The objective is to set the range of expected thicknesses in order to set up
the

Scan Bar

and its accompanying scale. Use of the Scan Bar is optional.

It provides an analog-like visual cue of acquired digital thickness readings.
If it is desired to use the Scan Bar, its scale can be set by establishing

Start

and

Stop

limits. It can start and end at any values within the NOVA TG950

specifications. Setting

Start

at a thickness somewhat below the minimum

expected thickness, and

Stop

at a somewhat greater thickness (say,

approximately 10%), than the maximum expected, will produce optimum
visual enhancement. For example, if the thickness of the test object is
expected to range between 0.050 and 0.100 inch (1.27 and 2.54mm), a
good

Start

point might be approximately 0.045 inch (1.14 mm) and the

Stop

point at approximately 0.110 inch (2.80 mm). This range will produce

the greatest visual motion within the range of expected thickness. On the
other hand, under the example above, if the scale is set to Start and Stop at
0.000 and 2.500 inches (0.00 and 63.50 mm), the range of motion between
the minimum and maximum expected thicknesses would be a very small
proportion of the total scale.

From the example above, where the approximate thickness range is
expected to be from 0.050 and 0.100 inch (1.27 and 2.54mm), set the

Stop

point first. W ith the Measurement Display open, and with

Start

highlighted,

as shown in the Figure above, use the Down ARROW to highlight

Stop

. If

the Stop value displayed is greater than the desired Stop point of 0.110 inch
(2.80 mm), press and hold the Left ARROW key. The Stop value will rapidly
scroll downward. At a Stop value approaching 0.110 inch (2.80 mm),
release the Left ARROW key, and toggle it until the desired value is
obtained. If the Stop value is less than that desired, use the Right ARROW
key to scroll/toggle the displayed value. To set the Start point at 0.045 inch
(1.14 mm), repeat the above procedure.

Finally, press the MENU button three times to back through the

Adjust

Scale

and

DISPLAY

Sub-Menus and return to the Measurement Display.

Observe that the Scan Bar scale ranges between the desired Start and Stop
values. Measurement readings between Start and Stop will produce the
analog view of the Scan Bar, and both the display reading and the Scan Bar
will remain displayed until the next valid reading is obtained.

If it is chosen not to use the Scan Bar,

Adjust Scale

settings can be set to

values below the Start value. Measurements within the expected range will

Nova Eclipse TG950 - Users Manual

produce an off-scale Scan Bar. Regardless of the settings of the Scan Bar
scale, thickness readings and the accuracy of readings are unaffected.

Backlite Sub-Menu:

In the DISPLAY Menu, toggle the Down ARROW to

highlight

Backlite

. Use the Right (or Left) ARROW to toggle through the

three selections,

Auto

Off

, and

. In the

Auto

mode the backlight will

turn on automatically when the transducer has valid coupling with the test
object, and will turn off automatically after approximately 5 seconds or until
the next measurement is made. In

Off

, the backlight will stay off

indefinitely. In

, the backlight will remain on continuously whenever the

gage is powered up.

If the gage is being used in an area with high ambient light, there is no need
to use the backlight. W ith the backlight turned

Off

, battery life will be

extended.

Contrast Sub-Menu:

If needed to accommodate unusual ambient

temperature or viewing conditions, setting the Contrast to 0-30 will produce
maximum contrast. To adjust contrast, with