LW Measurements HRB 224 Magnetic Force Balance - Manual (Page 12)

Operation
Calibration and Adjustment
Purpose
Calibration is the determination of the difference between the weight result and the true
weight(mass) of a sample. Calibration does not entail making any changes within the
balance.
Adjustment is the correction if any difference between the measured value display and the
true weight(mass) of the sample, or the reduction of the difference to allowable level within
the maximum permissible error limits.
Features
Calibration/adjustment can be performed only when:
í there is no load on the balance,
í the balance is tared, and
í the internal signal is stable.
If these conditions are not met, an error message is displayed.(refer to the Error information)
í The weight displayed for the sample on the balance must not differ from the nominal
weight by more than 2%.
í You can only use g as unit to make calibration.
External Calibration/Adjustment in Verified Balances of Accuracy class II
í When the balance is used in legal metrology, external calibration/Adjustment is blocked by
a seal over the menu access switch.
Important note for calibration/adjustment of the HRB-120.4,HRB-220.4,HRB-220.3,HRB-
320.3, HRB-420.3, HRB-520.3, HRB-620.3 model: Close the chamber before calibration/
adjustment to get collect result.
The permitted operating temperature range for balances used in applications subject to legal
metrology (legal for trade) is restricted as follows:
Balance of accuracy class I
+15 to 35 (+59 to +95 )
Balance of accuracy class II
+15 to 35 (+59 to +95 )
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