Collection:Flow indicators
Flow indicators show through a window whether water or a water-based liquid is flowing in the line, without a power supply. An impeller turns behind the window, so a stopped flow is easy to see;... Read more
Flow indicators
Flow indicators show through a window whether water or a water-based liquid is flowing in the line, without a power supply. An impeller turns behind the window, so a stopped flow is easy to see; they give no measured value in l/min. Brass indicators have a Pyrex glass window and suit water and mild water-based liquids up to +90 °C (≈194 °F). Sizes up to G 1" are rated to 25 bar (≈360 psi), G 1 1/4" and G 1 1/2" to 15 bar (≈220 psi). They work in any mounting position and flow direction, and the impeller speed gives a rough idea of the flow.
The polycarbonate version suits water up to 1 bar (≈15 psi) and +55 °C (≈131 °F). It only shows flow or no flow, also at very low flow. Its built-in filter is cleaned by back-flushing, and the flow runs in one direction only.
Flow indicators are made only for water and non-aggressive water-based liquids. For oil, or for a value in l/min, choose a variable area flow meter; for an electrical signal, choose a flow switch. Replacement sight glasses for the brass indicators are listed under flow accessories.