CHAPTER 4 TESTING
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Adventurer ™ Balances Service Manual
Fill in the worksheet (Table 4-4) with the ten (10) readings
.
Table 4-4. Repeatability Worksheet
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 = Square Root of (sum of (Delta x Delta) / 9)
5. Add the ten readings and divide the total by 10 to find the Mean (average).
6. Mean = (Reading 1 + Reading 2 + Reading 3 + Reading 4 + Reading 5
+ Reading 6 + Reading 7+ Reading 8 + Reading 9 + Reading 10) / 10
Mean
=________
7. Calculate the Delta for each reading and record in the work sheet.
Delta = Reading
– Mean
8. Calculate the Delta x Delta for each reading and record in worksheet.
9. Add the ten Delta x Delta values and divide by 9
10. Calculate the Standard Deviation by taking the square root of the result from Step 9.
Standard Deviation
=___________
Note:
If the balance does not meet specifications, move it to a suitable location, ensure
that it is level, and try again. If it still does not meet specifications, perform a service
calibration, and try again. (See Appendix B for Service Calibration.)
