Repeatability Worksheet - OHAUS PA64 Service Manual

CHAPTER 4 TESTING
4.4.6 Repeatability Test
n Reading
1
2
3
4
5
6
7
8
9
10
n = number of Reading
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
Calculate the Standard Deviation by taking the square root of the result from Step 9.
10.
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.)
Ohaus Corporation www.ohaus.com
TABLE 4-4. REPEATABILITY WORKSHEET
Delta = Reading – Mean
Mean = Sum of readings / 10
=___________
4-8
Delta x Delta
Delta = Reading – Mean
Pioneer™ Balances Service Manual