Fluke RUSKA 7350 - Manual (Page 36)

RUSKA 7350
Users Manual
4-12
Step Size
In addition to entering the pressure set-point by the key-pad, the pressure set-point can be
changed using the step function. The step function is used primarily when the operator is
taking pressure steps in equal pressure increments. The size of the pressure step is user
defined. From the Main Menu, press Menu [F6], Setup [F2], and then User [F2]. Using
the rotary knob, move the cursor to highlight Step Size. Enter the desired step size in the
current pressure units and press ENTER.
Bar Graph Maximum
The bar graph on the Main Menu screen can be scaled to match the device under test by
setting the full scale value of the bar graph.
Ready Tolerance
A Ready indication is generated when in control mode and the measured pressure is
reading within this ready tolerance value. When running an internal program, the ready
indicator is shown when the measured pressure is within the tolerance stored in the
program.
Gas Head Pressure Correction
The term “head height” refers to the vertical distance between the sensing element in the
device under test and the Calibrator’s pressure reference plane. Once the user inputs the
head height and selects air or nitrogen, the Calibrator automatically corrects for head
pressure.
1. The Pressure Reference Line on the Calibrator is defined as the bottom of the color
display where the display and the front panel join. This provides the reference plane
against which the device under test (DUT) pressure is measured.
2. Determine the vertical distance between the Calibrator Pressure Reference Line and
the reference plane of the device under test.
3. Press the Unit key found in the keypad and press in/mm [F1] to select either inches
(in) or millimeters (mm) for the head height entry.
4. The head height is set from the Menu | Setup | User. From the Main Menu (press
PREVIOUS until the Main Menu appears), press Menu [F6 ⎢Setup [F2] ⎢User [F2].
5. Press Medium [F3] to select either “Air” or “Nitrogen”. The selected units will be
highlighted.
6. Press Position [F4] to select if the position of the Device Under Test is either
“Above” or “Below” the 7350. The selected units will be highlighted and appear in
the Gas Head description.
7. Use the rotary knob to highlight the label “Gas Head”.
8. Use the numeric keypad to enter the height in the selected unit.
9. Press ENTER to accept the entry.
Atmosphere
The nominal barometric pressure value for the location that the Calibrator is utilized
should be entered for atmosphere. On tare mode instruments, this number is used to
calculate the density of the test port pressure medium and to correct for head pressure
variances between the reference port of the Calibrator and the DUT.