What do these products do in this instrument?
Piston pumps: discrete metering for fixed probes
Provide controlled displacement in the corresponding fixed-needle metering configuration, using a system-liquid or direct-contact path for delivery. Compare syringe-driven options for working stroke, capacity and installation conditions.
EA, SM and TM provide options for comparing capacity, wetted configurations and installation space. Verify actual doses from working stroke and the complete wetted path; check system-liquid drive and direct sample contact with the pump head separately.
Distinguish piston displacement from actual received volume
Piston pumps use controlled displacement for discrete aspiration and dispensing. Sample may enter the head directly or remain at the probe tip while system liquid transmits displacement; wetted coverage, priming and cleaning differ. Map aspiration, holding, dispensing and replenishment paths first, then relate stroke to probe-tip delivery.
Combine metering, valve positions and container actions into a complete cycle
Delivery requires coordination of metering drive, source switching and receiving-end actions. Usable capacity must cover working volume and other cycle displacements, with replenishment in permitted windows. Check tip droplets, bubbles and shared residual liquid through the complete path; remeasure received volume after changing pump heads, tubing lengths or interfaces.
Translate actual branch conditions into configuration requirements
| Condition | To confirm |
|---|---|
| Working stroke | Budget the fixed-probe transfer or dispensing sequence, including usable stroke, any system-liquid displacement and the permitted refill window. |
| Liquid contact and pressure | Define the fixed probe, its actual sample-contact or system-liquid path, source/receiver geometry and valve-state pressures. |
| Delivery and recovery | Measure actual receipt at each intended vessel or well with the fixed probe, including low source volume, idle periods, refills and internal/external probe washing. |
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 |
Confirm product roles in actual operation
Measure fixed-probe delivery with the actual liquids and receiving vessels or wells, including idle periods, refills and repeated dispensing. Evaluate probe washing and carryover through the complete sequence; disposable-tip handling is a separate architecture.
Are piston pumps of equal capacity directly interchangeable?
Also check wetted materials, interfaces, mounting, drive and pressure conditions. After replacement, recheck delivery, cleaning and first-dose recovery with the original sequence and actual liquids. Capacity is only one comparison criterion.
Nominal capacity and volume per step do not establish the minimum reliable pipetting volume. Disposable tips and reusable probes require different cleaning strategies.
References
View references (4)
- [1]FOREACH EA standard piston pump: configurations and specifications
- [2]FOREACH SM miniature piston pump: configurations and specifications
- [3]FOREACH TM ultra-miniature piston pump: configurations and specifications
- [4]Hamilton air-displacement pipetting channels, tips, monitoring and motion technologies