Where metered reagent addition and timing fit in the instrument
Configure for the method's reaction volume, addition order, mixing, temperature control and measurement window. Include bottle-change priming, first-dose recovery and waste capacity in the cycle, validating actual delivery and reaction results.
Adding the same volume at different times can change a reaction. Record each actual delivery, mixing, temperature control and measurement time, then assess the reaction result.
Product responsibilities in this operation
Piston drive creates controlled displacement, working with valve positions and the receiver to deliver this volume. Check working stroke and actual received volume separately.
For the water-analysis unit, confirm working volume, addition order, liquid-arrival delay, mixing dwell and detection trigger.
Organize the sequence by actual architecture
- List each reagent dose, addition order, reaction vessel, mixing and measurement window specified by the water-analysis method. Check actual formulations and wetted configurations.
- Prime the relevant source path and confirm valve position. Deliver each dose using the plunger working stroke, recording actual liquid arrival time and volume received at the cup.
- Coordinate delivery with method-required mixing, temperature control and waiting. Open the measurement window only after these conditions are confirmed. Pump motion completion alone does not establish suitable reaction conditions.
- Recheck the first dose and complete reaction blank after bottle changes or standby. Record dosed vessels and waste status, and handle partial delivery and restart according to the method.
Define operating conditions for this task
| To define | Details |
|---|---|
| Actual operating conditions | Working volume, addition order, liquid-arrival delay, mixing wait and detection trigger |
| Acceptance target | Measure each reagent addition and its actual arrival at the water-analysis reaction vessel. Confirm the method-required addition order, mixing, temperature conditions and wait before opening the measurement window. |
| Fault localization | Partial delivery, retained droplets or delayed mixing can alter the reaction while the programmed measurement window stays unchanged. Source recovery does not repair a vessel whose reagent sequence is already uncertain. |
Compare product configurations by the roles on this page
| Product | Configuration option | Conditions to verify |
|---|---|---|
| EA standard piston pump | Finite-stroke metering | Compare configurations by routine dose, total cycle displacement and wetted materials |
| SM miniature piston pump | Discrete metering in compact installations | Check installation space first, then validate working doses and actual accuracy |
| TM ultra-miniature piston pump | Discrete metering in limited space | Check installation space and configuration before measuring actual delivery; an ultra-miniature design does not imply a smaller reliable dose |
Validate operation results at the receiver
Measure each reagent addition and its actual arrival at the water-analysis reaction vessel. Confirm the method-required addition order, mixing, temperature conditions and wait before opening the measurement window.
After bottle changes or standby, check the first dose and complete reaction blank. Assess the method response with the actual formulations rather than substituting commanded pump steps for received volume.
Locate abnormalities and restore the next operation
Partial delivery, retained droplets or delayed mixing can alter the reaction while the programmed measurement window stays unchanged. Source recovery does not repair a vessel whose reagent sequence is already uncertain.
Identify the affected reaction vessel and completed additions, then handle its partial reaction according to the method. Restore the source and priming destination and verify first-dose delivery, arrival and a complete reaction blank before returning to analysis.
Internal reagent metering and reaction timing are separate from field-sample representativeness. Both must meet the water-analysis method.