Collection:Magnetic flow meters for conductive and dirty liquids

A magnetic flow meter, also called an electromagnetic or mag meter, measures electrically conductive liquids. The liquid passes through a magnetic field, and its movement creates a small voltage that two electrodes pick up. The voltage rises with the flow speed. Because nothing turns or projects into the bore, the meter measures liquids with solids or fibers without clogging. It works only on conductive liquids, which covers most water-based process liquids but rules out oils and other non-conductive media.

The 8041 and the 8045

Both are insertion meters and measure the same way. They differ only in whether the flow is shown at the pipe:

• Bürkert 8041: the standard meter, with a 4 to 20 mA signal, a pulse output, and a relay contact, but no display. It suits installations where the flow is read from a control panel.
• Bürkert 8045: adds a built-in display for a reading at the pipe, alongside the same output signals.

The S020 insertion fitting

The 8041 and 8045 do not connect to the pipe directly. Each meter is a measurement probe that sticks into the pipe through a mounting fitting, the Bürkert S020. The S020 is available in different pipe sizes and connection types (weld end, thread, clamp, flange, or solvent socket), which allows the same meter to be used for many different pipes. Each S020 fitting has a K-factor that the meter uses to read the correct flow rate for its pipe. The meter and a matching S020 are ordered together; without the fitting the meter cannot measure.

Frequently asked questions

Why pick magnetic over a paddle wheel meter?

A magnetic meter has no moving parts in the flow, so solids and fibers pass through without jamming it, and it is accurate even on dirty liquids. A paddle wheel needs a clean liquid to spin freely. The trade-off: a magnetic meter measures only conductive liquids.

Can a magnetic meter measure oil or pure water?

No. The measurement relies on the liquid conducting electricity. Oils, fuels, and demineralized water do not conduct, so a magnetic meter cannot measure them. For a clean non-conductive liquid, choose a paddle wheel meter.