Sartorius Master Pro LA12000P, Service Manual

Page: 38 / 64

38
G4
G3
G2
1
0
P
T3
G1
2 3 4
P
P
P
T1
T2
Linscha.EPS
Displayed
Value
Test
Weight
Checking the Linearity on Balances with More Than 1,000,000 Digits and
PolyRange Balances
Note: For balances with a resolution of more than 1,000,000 digits (e.g., the
LP1200S) and for PolyRange balances, the linearity is checked using the rela-
tive method.
4 measurements are taken.
For the first measurement, the test weight is placed on the balance without a
tare load.
For the following measurements, the test weight is measured 3 times, with 3
different tare weights.
– See the “Service Specifications Sheets for Master
pro
Balances” for the re-
quired test weights and tare weights.
– Unload the balance and tare it.
– Center the test weight on the weighing pan.
– Write down the value displayed at stability (G1).
– Unload the balance.
– Place the first tare weight on the weighing pan and tare the balance.
– Center the test weight on the weighing pan.
– Write down the value displayed at stability (G2).
– Unload the balance.
– Place the second tare weight on the weighing pan and tare the balance.
– Center the test weight on the weighing pan.
– Write down the value displayed at stability (G3).
– Unload the balance.
– Place the third tare weight on the weighing pan and tare the balance.
– Center the test weight on the weighing pan.
– Write down the value displayed at stability (G4).
– Unload the balance.
– The linearity error is calculated according to the following formula:
linearity Error L = Highest disp. value – lowest disp. value
—————————————————
2
– If the resulting linearity error exceeds the tolerance limits, the linearity must
be re-adjusted (LP see page 13 / LA see page 23, “External Lineariza-
tion”).