Adjusting The Preload; Off-Center Load; Checking The Off-Center Load - Sartorius Basic plus Service Manual

Note:
22

Adjusting the Preload

- The test procedure is similar to that described under "Checking the Preload"
on the previous page.
- Use the one of the following procedures to change the preload:
- Basic Balances with brass-system (small): Remove preload weights (408)
plus
from the preload spindle (409), or add weights to the spindle; fine
adjustments are made by moving the preload weights (408) that are on the
spindle (409).
- Basic Balances with single-casting block system (small): Remove preload
plus
weights (401) from the lever (403) via the magnets (414) or add weights
to the lever.
- During the adjustment, the preload weights remain on the balance.
- Check the display on the digital voltmeter after each change and compare
the voltage display to that given in the data sheet.
- If the preload voltage measured is within the tolerance range given, close
the balance (see page 27) before continuing with the following
adjustments:
Off-center load (see page 22),
Linearity (see page 25)
External adjustment/calibration (see page 25)

Off-Center Load

Checking the Off-Center Load

The procedure described in the following for checking the off-center load is
based on the Sartorius in-house standard no. 1-150, point 1.5.1 "Checking
the Off-Center Load Using 5 Test Positions". All off-center load values given in
the "Adjustment/Calibration Data Sheets for Basic
on this standard.
- The data for off-center load checkweights, diameter, off-center-load test
area and tolerance values are contained in the "Adjustment/Calibration
Data Sheets for Basic Balances".
plus
- Place the test weight on position 1 on the weighing pan; if the balance has
a draft shield, close the draft shield. Press »
- Place the test weight on positions 2 through 5 in sequence and write down
the values, with plus or minus sign, displayed at stability and with the draft
shield (if present) closed.
Basic Balances with diagonally installed weighing systems (brass-system
plus
(small) and strain gauge system): The diagram at the left applies to Basic
balances with rectangular weighing pans.
Example (BP 210 S):Pos. 1 »
Pos. 2
Pos. 3
Pos. 4
Pos. 5
Balances" are also based
plus
« to tare the balance.
« 0.0000 g
+ 0.0015 g
+ 0.0022 g
- 0.0012 g
- 0.0018 g
plus