Fluke Biomedical Victoreen 07-494, Руководство оператора

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Calibration and Adjustment
Low Battery Threshold Adjustment
5
5-1
Section 5
Calibration and Adjustment
This instrument has been factory calibrated. Recalibration should be performed by the factory or a
qualified calibration facility every 12 months. Other than calibration, there are six potentiometers which
may require adjustment. The procedures are outlined in this Section. Refer to Figure 5-1 for
potentiometer location
5.1 Low Battery Threshold Adjustment
Potentiometer R25 adjusts the threshold for indicating LO BAT on the LCD display. Use the following
procedure:
1. Open the battery compartment on the rear panel.
2. Remove and disconnect the battery.
3. Connect a voltmeter between battery plus (TP3).
4. Connect a voltmeter between battery plus (TP3) and analog ground (TP4).
5. Turn on the power supply and adjust it for 9 V.
6. Turn on the kVp Meter. The voltmeter should read between 2.4 V and 3.2 V.
7. Slowly decrease the power supply voltage until the voltage at the test point starts to drop (between
6.5 V and 7.5 V).
8. Slowly increase the power supply until the voltage across the test points just returns to the value it
had prior to dropping off.
9. Turn R25 until LO BAT disappears from the display.
10. Turn R25 slowly in the opposite direction just until LO BAT reappears on the display.
11. Connect the voltmeter between analog ground and the power supply negative terminal.
12. Increase the power supply voltage until the voltmeter reads 4.5 V, being careful not to exceed 9 V
from the power supply. LO BAT should turn off at this point.
13. Replace the battery and close the battery compartment.