Tolerances; Performance Tests - OHAUS NV212 Service Manual

4.5 PERFORMANCE TESTS

Accurate performance of the Navigator scales is determined by a series of four performance tests.
The displayed readings are compared with the tolerances listed in Tables 4-2 and 4-3. Tolerance
values are expressed in counts. A one-count difference is shown in the last digit on the scale
display.
Model
NV212
NV311(N or M)
NV511
NV1101
NV2101
NV4101
NV5101
NVL511
NVL1101
NVL2101
NV3100(N or M)
NVL5101
NVL10000
NVL20000
NVT1601
NVT1601(N or M)
NVT3201
NVT3200(N or M)
NVT6400(N or M)
NVT6401
NVT10001
NVT16000
NVT16000(N or M)
NOTE:
The following performance tests are used to evaluate scale operation before and after repairs. The
scale must meet the requirements specified in each test as well as the specifications listed in Table
4-2. Before proceeding with the following tests, the scale should be calibrated. (See Appendix A)
4.5.1 Precision Test
The Precision Test is a quick test that measures the deviation of a limited number of weight
readings, which should match the specification for each model, listed in Tolerance Table 4-2.
1. Power on the balance. The reading on the display should be 0g.
2. Select a mass weighing near the maximum capacity of the balance, and place it on the center
of the Pan. Observe and record the reading.
3. Remove the mass. The reading should return to 0g ± the precision tolerance in Table 4-2.
Navigator Series Service Manual
TABLE 4-2
Precision (d) Repeatability (d)
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
27

TOLERANCES

Linearity (d)
2
1
2
2
2
2
2
2
2
2
1
2
2
2
2
1
2
1
1
2
2
2
1
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CHAPTER 4 TESTING
OCL
±2 ±3
±2 1 MPE
±2 ±3
±2 ±3
±2 ±3
±2 ±3
±2 ±3
±2 ±3
±2 ±3
±2 ±3
±2 1 MPE
±2 ±3
±2 ±3
±2 ±3
±2 ±3
±2 1 MPE
±2 ±3
±2 1 MPE
±2 1 MPE
±2 ±3
±2 ±3
±2 ±3
±2 1 MPE