Fluke RUSKA 7252, User Manual

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RUSKA 7252
Users Manual
6-2
3. Press Electrical [ F1 ]. The electronics self test will run and display the results.
The electronics test runs eight sets of tests on various parts of the electronic modules.
Table 6-1 describes these tests and the possible actions needed if a test fails. The
pneumatics test runs nine tests on the pneumatics module.
Table 6-1. Electronics Self Test
Test Description Action on Failure
Processor Tests the processor chip Replace processor board.
Clock Tests the real time clock Replace processor board.
Timer Tests the 10 ms interval timer Replace processor board.
EEPROM Tests the nonvolatile memory Replace processor board.
Oven Tests operation of the sensor oven Replace sensor assy.
Allow oven to warm up.
Removing the Calibrator’s Cover
The Calibrator should be kept clean and completely assembled at all times. Operating the
Calibrator without its cover affects the Calibrator’s thermal gradients and therefore may
reduce precision. If it becomes necessary to remove the Calibrator’s cover, follow the
instructions below.
WX
Warning
The Calibrator should only be opened by qualified
electrical/mechanical service technicians. Lethal voltages are
present and exposed in the power supply and display.
1. Turn off the Calibrator and disconnect the power cord from the Calibrator.
2. Locate and unscrew the four screws that secure the cover to the back panel.
3. Place your hands near the middle of the cover and slide the cover towards the
Calibrator’s back panel.
4. Lift up on the cover. With the cover removed, use typical electronic cleaning tools to
remove any accumulated dust from inside the instrument.
5. Replace the cover before resuming operation.
Moisture Filter
The Bourdon tube sensor is hydroscopic. An external desiccant filter prevents
introduction of moisture and is strongly recommended for high humidity areas. The filter
should be replaced annually. The moisture filter is used with the reference port only
(absolute only instruments do not need a moisture filter).
Particle Filters
Refer to Appendix A for air supply quality requirements. During normal operation, the
Calibrator transfers gas both into and out of the device under test (DUT). When necessary,
the user is expected to use and maintain an in-line disposable particle filter to protect the
Calibrator’s pneumatics from any contamination that may exist in the DUT.