OHAUS EC Series, Руководство по обслуживанию

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3-9
CHAPTER 3 SCALE TESTING AND CALIBRATION
3.6.2 Repeatability Test (Cont.)
Test Procedure:
1. Zero the scale.
2. Using a test mass approximately 1/2 the capacity of the scale, 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 this worksheet with the ten (10) readings.
n Reading Delta = Reading – Mean Delta x Delta
1
2
3
4
5
6
7
8
9
10
n = number of Reading Mean = Sum of Readings / 10 Delta = Reading – Mean
Standard Deviation = The Square root of (the sum of the (Delta x Delta) / 9)
5. Add the ten readings and divide the total by 10 to find the Mean (average).
Mean = (Reading 1 + Reading 2 + Reading 3 + Reading 4 + Reading 5
+ Reading 6 + Reading 7+ Reading 8 + Reading 9 + Reading 10) / 10
Mean =________ Mean =________
Mean =________ Mean =________ Mean =________
6. Calculate the Delta for each reading and record in the work sheet.
Delta = Reading - Mean
7. Calculate the Delta x Delta for each reading and record in worksheet.
8. Add the ten Delta x Delta values and divide by 9
9. Calculate the Standard Deviation by applying the square root of the result from step 8.
Standard Deviation =___________