OHAUS Explorer Balances, Руководство по обслуживанию

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CHAPTER 4 - TESTING
Explorer
®
Series Service Manual 47 Ohaus Corporation www.ohaus.com
4.4.2 Repeatability Test (non-approved models)
The repeatability specification is defined as the Standard Deviation value derived from a set of
weight readings. This test uses more weight data than the Precision Test and will allow for
occasional weight deviations due to testing variations.
Note: The required method for approved models (OIML and NTEP) is shown in the following
section.
Requirements:
x
To perform this test a single mass must be used for all readings.
x
The test mass should be approximately ½ of the capacity of the instrument.
x
Wear gloves when handling the mass.
Set Up:
Before starting a repeatability test, set up the instrument as follows.
Enter the service menu (see
Appendix B.1
) and adjust and record the following settings:
x
Set the Stability setting to 0.5d (its lowest setting).
x
Set the Filter level to “Middle” .
x
Set the AZT (Auto Zero Tracking) to .5d (its lowest setting). Do not turn it off.
Enter the User Menu (see 1.8.1) and adjust the following settings:
x
Set the instrument to display the same units as the performance specifications.
(Usually kg, g, or mg)
Record Test Parameters:
x
Stability Setting = ____________
x
Filter Level Setting = ____________
x
Auto Zero Tracking Setting = ____________
x
Displayed Units = ____________
x
Mass Used = ____________
Test Procedure:
1. Zero the instrument.
2. Using a test mass approximately half the capacity of the instrument, place the mass on the
center of platform. Record the reading on the worksheet provided.
3. Remove the mass from the platform.
4. Repeat this test starting at Step 1 until you record a total of ten readings.
Fill in the worksheet with the ten (10) readings.