Magnetic Flowmeters are designed to measure the flow of electrically conductive liquids in a closed pipe. There are no moving parts to wear and no pressure drop other than that offered by the section pipe of equal length and inside diameter. They measure the flow of rate based on the voltage created between two electrodes as the water passes through an electromagnetic field. The voltage depends on magnetic field strength. This is also known as electromagnetic flowmeters or induction flowmeters. This places electric coils around the pipe for the flow to be measured and sets up a pair of electrodes across the pipe wall or at the tip of the flowmeters. These are used to measure flow of conductive liquids in both forward and reverse directions. They do not work with hydrocarbons distilled water and many non-aqueous solutions. The advantage of these flowmeters is no obstruction to flow, minimal head loss, wide range of sizes and no moving parts. This is based on Faraday's law.