Flow Measurement : Magnetic Flow meters -Application Advantages and Disadvantages Installation

Application of Magnetic Flow Meters : Magnetic Flow meter measures the volumetric rate of flow any liquid that has adequate electrical conductivity. Most petroleum hydrocarbons have insufficient conductivity to be measured with a magnetic flow meter. It is rarely used in Petroleum Industry. Magnetic Flow meters are widely used on slurries <img src="/uploads/default/56/5c9c5b146c7a39a8.gif" alt="Magnetic Flow meter working Priciple"width=“520” height=“271”>

Advantages of Magnetic Flow Meter : 1.They respond only to the velocity of Fluid .Independent Density Viscosity and Static Pressure 2.High Rangebility 10:1 3.Bidirectional Flow Measurement 4.Fluid Temperature range -40 Deg C to +260 Deg C 5.Pressure Drop is negligible 6.Wide Variety of Size

Disadvantages of Magnetic Flow Measurement 1.Conductivity of the process fluid should be greater the 2 micromhos per centimeter 2.Special care is required for erosive application 3.Difficulties in on site calibration 4.High cost 5.Large Sizes are very heavy

Installation Consideration : Magnetic Flow Meter consist of two parts Primary elements installed directly in the processline Secondary elements is an electronic transmitter Magnetic flow meter tube may be installed in any position but it must run full of liquid for accurate measurement

I have a electromagnetic flow meter which gives 4 to 20mA. I want to use this to control a pump speed.would u like to help me how can i write a program in LAD language