What do these products do in this instrument?
Syringe pumps: aspiration, holding and reagent dispensing
In syringe-metered branches, connect reagent sources to delivery points and use valve positions for aspiration, holding and dispensing. Compare with piston configurations by actual architecture and schedule replenishment within permitted detection windows.
HLD and HMD organize aspiration/dispensing paths with rotary and solenoid valves respectively. Capacity budgets include useful volume, holding stages and replenishment points; valve states and pump actions together create each delivery.
Organize syringe metering around aspiration, holding and dispensing
Syringe drives use controlled displacement for aspiration, holding and dispensing. With direct contact, source liquid enters the metering chamber; with system-liquid drive, sample can remain at the probe tip or a designated tube segment. Define wetted coverage before capacity, cleaning and replenishment. For repeated dispensing, track current inventory, delivered volume and next replenishment time.
Further technical reading
Map valve connections to every action
Check port connections, opening/closing sequence and power-off state separately for rotary- and solenoid-valve configurations. Changing source does not automatically remove old liquid from the chamber or shared tubing. Plan flushing for formulation and residue requirements, then evaluate the first dose after switching and dose-to-dose variation.
Translate actual branch conditions into configuration requirements
| Condition | To confirm |
|---|---|
| Stored volume and timing | Define volume per operation, consecutive dispensing count, holding time and permitted replenishment window. |
| Valve positions and destinations | Provide a source, receiver and waste port diagram with open/closed and power-off states. |
| Liquid changes and first dose | Check shared residue, priming destination and actual received volume after standby or source changes. |
| Operation | Specific operating conditions |
|---|---|
| Sample aspiration and transfer | Actual sample volume, remaining source volume, probe-tip height, aspiration/dispensing speed and system liquid |
| Metered reagent dispensing | Dose per operation, total cycle volume, replenishment/bottle-change interval, backpressure and receiving geometry |
Compare product configurations by the roles on this page
| Product | Configuration option | Conditions to verify |
|---|---|---|
| HLD rotary-valve syringe pump | Aspiration, holding and dispensing with a rotary valve | Check source/outlet valve positions, capacity budget and replenishment timing |
| HMD solenoid-valve syringe pump | Metered aspiration and dispensing with solenoid valves | Check open/closed and power-off states, working volume and replenishment cycle |
Related operations and architecture comparisons
Sample aspiration and transfer
Low remaining volume, probe contact with a wall and aspiration/dispensing reversals may alter delivery. First measure error in the target container, then assess residue using a blank after a concentrated sample; one calibration cannot address both issues.
Metered reagent dispensing
For repeated dispensing, record usable doses per fill and replenishment points. Confirm restoration of the liquid column after replenishment before evaluating the first dose. Retrying an interrupted action must also avoid duplicate addition to the same cuvette.
Confirm product roles in actual operation
| Operation | Measurements and observations | Priority checks |
|---|---|---|
| Sample aspiration and transfer | Measure actual delivery at the receiver, covering routine small volumes and maximum task volume, first dose after idle, sample changes and high/low concentration sequences | Air aspiration, clots/particles, probe contact with a wall or leakage alter actual delivery |
| Metered reagent dispensing | Use actual media to check first, middle and last doses and delivery after bottle changes; confirm received volume and timing rather than substituting commanded steps for volume | Empty sources, bubbles, nozzle droplets and backpressure changes affect first or last doses |
Check delivered volume, first dose after idle and residue after high/low concentration switching at the receiving location.
For repeated dispensing from one chamber, is checking total volume enough?
Measure each received dose, especially the first and last. Even when total volume is near target, individual errors may differ. Relate replenishment, valve switching and receiving actions to each result.
The assay determines sample suitability; full-scale metering specifications cannot replace small-dose and complete-instrument results.