Specifications

RUSKA 7250, 7250i, 7250xi & 7250LP
Users Manual
6-8
3. If desired, change the Calibrator’s units of measure (see Chapter 4) to match those of
the calibration standard.
4. To access the Calibration screen, from the Main Menu, select MENU | CALIBRATE.
5. Select the atmospheric sensor by pressing the Sensor [F6] key until the words
Atmospheric Sensor are displayed above the calibration coefficients.
6. To begin the calibration process, press CALIBRATE. If the calibration access code is
enabled, enter it at the prompt. The first Calibration screen will appear.
7. You will use the calibration standard to apply the various pressures that will be
requested by the RUSKA 7250. The screen will display a table noting the following
information;
Step The pressure step in the calibration sequence.
Apply The pressure that the standard is to generate to the Calibrator.
Actual The actual pressure value that was generated by the standard when the
point was accepted.
8. The Actual value will be highlighted. This is your first pressure point in the
calibration procedure. This calibration requires the generation of two pressures within
the range of 700 to 1100 mbar absolute. The selected pressures should be spaced as
far apart as possible within the allowable range.
9. Generate the first pressure. Enter the actual value of the applied pressure generated
by the standard and press ENTER.
10. Generate the second pressure. Enter the actual value of the applied pressure generated
by the standard and press ENTER.
11. The RPT sensor is now linearly compensated. Once the calibration procedure is
complete, the user should verify several pressure readings against the pressure
standard. If there are variances beyond the stated precision, then an error was
probably made in generating one of the calibration pressures, and the calibration
procedure should be repeated.
12. Remove the pressure source from the Reference Port.
Vacuum Sensor Calibration—Optional Case Reference Sensor
A span correction can be applied to the vacuum sensor. This correction is done using the
RUSKA 7250’s software and can be performed without removing the vacuum sensor
from the Calibrator chassis.
1. Place the Calibrator in Measure mode. Remove all pressure sources from the system.
2. The Vacuum sensors are located inside the black sensor oven assembly. Connect a
pressure standard physically as close to the vacuum sensor as possible. You may
wish to remove the top cover of the instrument and connect directly to the pressure
ports going into the quartz sensor oven assembly. Note, on the RUSKA 7250 each
sensor will have its own independent vacuum sensor.
3. If desired, change the Calibrator’s units of measure (see Chapter 4) to match those of
the calibration standard.
4. To access the Calibration screen, from the Main Menu, select MENU | CALIBRATE.
5. Select the vacuum sensor by pressing the Sensor [F6] key until the words Vacuum
Sensor is displayed above the calibration coefficients.
6. To begin the calibration process, press CALIBRATE. If the calibration access code is
enabled, enter it at the prompt. The first Calibration screen will appear.