The battery-operated vacuum pump is designed to provide vacuum to suction lysimeters installed in the field. Suction lysimeters are frequently installed at locations where line power is not available. This small vacuum pump will draw enough vacuum (maximum vacuum 340 mbar) to extract pore water into suction lysimeters when the soil or porous matrix are relatively moist (matrix potential greater than -200 mbar).

In reality if the soil or porous material is dryer than a water content equivalent to –200 mbar matrix potential, the hydraulic conductivity of the soil immediately around the lysimeter is so low as to make extraction of soil pore water very difficult. This is especially true for sandy soils, and coarse textured materials.

The battery and vacuum pump are enclosed in a strong container. It measures 23 x 20 x 10 cm and weighs 2.7 kg. On a fully charged battery the pump can run continuously and draw vacuum for 3 to 4 days.