OHAUS DISCOVERY BALANCE, Руководство по обслуживанию

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CHAPTER 4 TESTING
4.1 TESTING
After servicing the balance, an operational test and various performance tests should be made
to confirm that the balance meets specifications. Turn the balance on and allow it to warm up
for at least one hour before performing these tests.
NOTE:
Make sure the test area is free from drafts and that the balance rests on a level and
vibration-free surface. The masses used for final calibration must be adjusted to ASTM
Class 1 or OIML Class E1 tolerance or better.
4.1.1 Operational Test
1. Connect a functioning AC Adapter to the balance Power Jack located at the rear of
the balance.
2. Plug the AC Adapter into a suitable power source. If the AC Adapter supplied with
the balance is rated for a different voltage, use an appropriate adapter to match the
supply voltage.
4.1.2 Models Segment Display Test
1. Turn the balance on by pressing ON/ZERO Off , all segments are enabled
and displayed briefly, then followed by a software revision number.
See Figure 4-1 for full display.
Figure 4-1. LCD Full Display for Discovery Balance.
2. Tare the balance. The display should indicate a zero weight.
4.2 Load Cell Performance Tests
4.2.1 Off-Center Load Test
The Off-Center Load Test is used to determine whether displayed weight values
are affected by moving the sample to different areas of the Pan.
1. Place half of the balance capacity in the center of the Pan.
2. Note the reading.
3. Move the mass halfway (between the center and the edge) to the front of the Pan.
Note any differences in the displayed weight reading.
4. Repeat the test for the back, left, and right position of the Pan.
Discovery Balance Service Manual 4-1 Ohaus Corporation www.ohaus.com