OHAUS EC Series, Руководство по обслуживанию

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3-8
CHAPTER 3 SCALE TESTING AND CALIBRATION
3.6 PERFORMANCE TESTS
Figure 3-3. Segment Display.
3.6.2 Repeatability Test
Repeatability is the Standard Deviation of a set of similar weight readings.
Requirements:
To perform this test a single mass must be used for all readings.
The test mass should be approximately 1/2 of the capacity of the scale.
Before starting a repeatability test, set up the scale as follows:
Set Up:
Enter the menu and adjust and record the following setting.
A. Set the Filter level to 1.
B. Set the AZT (Auto Zero Tracking) to 1d.
C. Set the scale to display the same units as the performance specifications.
D. Set the Zero return to 0.
Record Settings:
Filter Level Setting = ____________
Auto Zero Tracking Setting = ____________
Displayed Units = ____________
Zero Return = ____________
Mass Used = ____________
Accurate performance of the EC Series Scales is determined by a series of three performance tests,
Repeatability Test, Off-Center Load Test and Linearity Test. These tests are used to evaluate the scale
performance before and after repairs. Each scale tested must meet the requirements specified in each test
as well as the specifications listed in Table 3-4. A scale passing each of these three tests complies with
Ohaus specifications. A segment display test determines if the display is working properly.
3.6.1 Segment Display Test
Connect the AC Adapter into a suitable power source and connect it to the scale. Turn the scale on, all
999999 segments are displayed followed by a countdown of 8's. 7's, 6's and so on until all zeros are
reached briefly followed by a software revision number. This is a segment display test. Figure 3-3
illustrates the starting of the display test.