OHAUS Explorer Balances, Руководство по обслуживанию

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CHAPTER 4 - TESTING
Explorer
®
Series Service Manual 49 Ohaus Corporation www.ohaus.com
Repeatability Test – Approved models
This test is a variation of the test above. Rather than determining acceptance based on the
standard deviation of the errors, MPE is used. The other variation is that 2 series of weighings are
used, one near 50% of max and the other near 100% of maximum capacity.
1. See Table 1-1 to determine the two weight values that must be used.
2. Record 10 reading using each weight value. Zero the balance between each reading if
necessary.
3. The difference between the results of the 10 readings must be less than the absolute value
of the Maximum Permissible Error (MPE) for the load. The MPE for each load in grams is
given in Table 1-1.
4.4.3 Linearity Test
This test is used to determine the linearity of the unit throughout its operating range. The masses
used to perform this test can be utility masses.
This is a reference test for approved balances as there is no linearity specification. The approved
models should be able to pass this test so it is still valid to determine balance performance.
NOTE:
The balance must pass the Precision and Repeatability Tests, and be calibrated before the
Linearity Test is performed.
TABLE 4-3 LINEARITY TEST - REFERENCE AND LOAD MASSES
Model Reference Mass Load 1 Load 2 Load 3
EX124
30g 30g 60g 90g
EX224
50g 50g 100g 150g
EX324
75g 75g 150g 225g
EX223
50g 50g 100g 150g
EX423
100g 100g 200g 300g
EX623
150g 150g 300g 450g
EX1103
250g 250g 500g 750g
EX2202
500g 500g 1000g 1500g
EX4202
1000g 1000g 2000g 3000g
EX6202
1500g 1500g 3000g 4500g
EX10202
2500g 2500g 5000g 7500g
EX6201
1500g 1500g 3000g 4500g
EX10201
2500g 2500g 5000g 7500g
EX12001
1500g 1500g 3000g 7500g
EX24001
5000g 5000g 10000g 17500g
EX35001
5000g 5000g 10000g 25000g
NOTE:
All masses are nominal values. Be certain to use the same reference mass throughout the
procedure.
1. Place the Reference Mass on the Balance, record the weight and remove.
2. Place Load 1 on the Balance and press TARE.
3. Place the test mass on the Balance, record the weight and remove.
4. Place Load 2 on the Balance and press TARE.