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Fluid path
Wavie moves every liquid through one shared path: a pump, a rotary valve and the cell.
A peristaltic pump driven by a small stepper motor (NEMA 11). Rollers squeeze a length of tubing, so liquid only ever touches the tube.
| Resolution | About 2,300 motor steps per millilitre, so one step moves roughly 0.0004 mL |
| Direction | Both. The pump fills the cell and empties it |
| Calibration | Each unit is calibrated by weight, in both directions, and the result is stored on the unit |
The tubing wears and is replaceable.
A stepper motor (NEMA 17) turns the valve to one of eight ports, 45° apart.
| Ports | Use |
|---|---|
| 6 | Reagents |
| 1 | Tank sample |
| 1 | Waste |
There is no spare port: six reagents, sample and waste use all eight.
A limit switch marks the home position. Wavie homes the valve before every test, then counts steps to reach a port, and takes the shortest way round. If the count ever disagrees with the switch, it reports a fault instead of guessing.
The cell holds up to 3.5 mL. The firmware treats that as a hard limit and refuses any step that would overfill it. A stirrer under the cell mixes the sample after each addition.
The valve, the pump and the cell are joined by flexible tubing through a printed manifold. Tubes for the six reagents, the sample and the waste leave the tower at the side.
The parts
System
Owning one