What this means for your laboratory: no handwritten weights to retype and no transposed digits. The balance connects to a serial (RS232) port on the weighing workstation, and the connection is saved with the instrument, so every workstation that reads that balance uses the same settings.
What happens at the bench
The analyst works at the balance, not at the keyboard. Weighing a full worksheet is one key press per sample.
- One key per sample The analyst selects the first weight cell and starts on-line reading. Each press of the balance's print or transfer key writes the weight into the current cell and moves down to the next sample, skipping locked and protected cells.
- Every weight keeps its evidence With each weight, OnWSH records the balance it came from, for example BAL-1, the value read, the line the balance sent as the cell note, and the date and time of the reading.
- Calibration dates in view If the balance's calibration or service date has expired, OnWSH shows the instrument's dates before reading starts. The calibration and service dates of any instrument can be checked from one of its readings at any time.
- Weighing sheets when paper is needed The worksheet prints as a weighing sheet with the sample and QC rows in order and columns such as Weight and Volume, so the bench and the LIMS work from the same list.
From weight to result
The weight feeds the calculation defined in the approved template, with no copy step in between. For example, 1.0000 g, 50 mL, dilution 1 and a Cu reading of 25 mg/L give 0.125% Cu: reading × volume × dilution ÷ weight ÷ 10000. When reading stops, the worksheet keeps a record of the session with the lines received, the number of readings and the analyst.
Balances and their connection
Your balance's settings are set once, per instrument. OnWSH includes a generic Balance parser plus parsers for specific models, set with the port, baud rate, data bits, stop bits and parity of your balance. Balances sit alongside AAS, ICP, XRF, carbon/sulfur analyzers, calorimeters and titrators in a connection catalogue of 150+ instruments from about 40 brands.
Frequently asked questions
What does an RS232 connection need?
A free serial port on the workstation (COM1 to COM8), the balance's communication settings and the balance registered as an instrument in OnLIMS. Editing the connection is reserved for users with that permission.
How is a captured weight used in a calculation?
The approved template defines the calculation. For example, 1.0000 g, 50 mL, dilution 1 and a Cu reading of 25 mg/L give 0.125% Cu: reading × volume × dilution ÷ weight ÷ 10000.
How do I finish a weighing session?
Stop on-line reading and save the worksheet. The worksheet then keeps a record of the session with the lines received, the number of readings and the analyst.
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