Conductivity

Conductivity-type level transmitters and switches operate by utilizing the electrical conductivity of a liquid—typically a water-based or acidic medium—to complete an electrical circuit between a sensing electrode and a reference point, such as the tank wall or a secondary probe. When the liquid level rises and makes contact with the probe, it creates a low-resistance path that allows a small, low-voltage current to flow, triggering a signal that indicates the presence of the fluid. While switches are used for point-level detection to control pumps or prevent overflows, conductivity transmitters can provide multi-point or continuous monitoring by using multiple probes of varying lengths, making them a robust and low-maintenance solution for conductive liquids where no moving parts are desired.