28 |
Testing and Adjustment Sequence on Balances/Scales with Monolithic Weighing
Systems
Preparations: Place the analytical balance on a solid, level surface that is free of vibration,
e.g. a stone table. Level the analytical balance using the level indicator. Turn the
balance/scale and allow it to warm up for about 4h-24h.
Note: Testing must be carried out according to the following Sartorius Standard Operating
Procedure for Testing WKD-037-02 and WKD-038-02. They are also the equivalent of
the given adjustment data as described in this service manual.
You will need to check and, if necessary, adjust the following:
1. Overload stop
2. Repeatability
3. Off-center loading error
4. Span adjustment
External span adjustment
Overwrite internal calibration weight
Internal span adjustment
5. Linearity
External linearization
Overwrite internal linearity weight
Checking the Overload Stop
Note: Overload stops no longer need to be checked monolithic weigh cells.
Setting the Overload Stop
It is no longer necessary to set the overload stops. They are factory set and adjusted.
Checking the Repeatability (Standard deviation)
- Select the test weight from the „Adjustment Datasheet (see Page 42-43).
- Unload the weighing pan and zero the balance/scale using the t key.
- Center the test weight on the weighing pan.
- Write down the weight displayed.
- Repeat the procedure five times.
- The repeatability is calculated from the 6 weighing operations as follows:
(Max. value displayed - Min. value displayed) / 3
- Compare the calculated value with the given tolerance.
If the calculated value is not within the given tolerance, it may be due to one
of the following reasons:
- The weighing system needs to be cleaned
- Mechanical parts are in the weighing system
- Bent / defective bending elements
Waags_Just.eps
Front
Balances/Scales with Monolithic Weighingssystems