Electromagnetic flowmeter features

Features of electromagnetic flowmeter

The electromagnetic flow meter is a velocity flow measurement device. It measures the volume flow of conductive liquids. It not only has on site display. It can provide standard current signals like 4-20ma. for recording and adjust controls to realize automatic detection and long-distance signal transmission. It can measure the flow of many kinds of liquids. Like slurries in water, wastewater, chemical, dairy, and so on. It can use in many kinds of industries. Food and beverages. Pharmaceutical and medical. Petrochemical and steel. Paper and mining, etc. The structure of the instrument has compact and remote type.

  • There are no moving parts in the measuring tube, so it is convenient for maintenance. No flow-blocking parts, so it has a quite low-pressure loss.
  • The lowest conductivity of the tested liquid is ≥20μs/cm, with various lining materials. It can use to measure the flow of various acids and alkalis. Salt solutions, slurry, mineral pulp and paper pulp, etc.
  • The performance of the instrument is not affected by the properties of the materials. Such as corrosiveness, viscosity, pressure, density, acidity, and alkalinity. The induction voltage signal of the sensor has a linear relationship with the average flow rate. It ensure high accuracy.
  • It has low-frequency rectangular wave excitation. But it does not affect by the power frequency and various interferences. so that it ensures stable and reliable measuring.
  • Not affected by the direction of the fluid, both positive and negative flow can be accurately measured.
  • With LCD backlit display, parameters can be modified on site conveniently. With empty pipe detection/alarm function, the unit can detect if the pipe is full or drained /empty.

Installation guidelines

Please pay attention to the following requirements when choosing the installation location of an electromagnetic flowmeter. It needs to ensure the stable and reliable performance of the sensor,

  • Keep away from equipment with a strong magnetic field as far as possible. Such as large motors, large transformers, frequency conversion equipment
  • Please better install in a dry and ventilated place, not a humid
  • The environment temperature should not more than 60 °C and relative humidity not more than 95%.
  • Choose a place where is convenient for operation and to avoid negative pressure. The flow sensor should not install at the pump inlet. But at the pump Valves should always be mounted on the downstream side of the flow sensor.

Installation requirements

Please pay attention to the following requirements when choosing the line position.

  • The flow sensor needs to mount on a vertical position. If the flow sensor is mounted vertically, the flow direction should always be upwards.
  • The medium should always be full-filled in the pipe from the installation location. It helps to avoid gas adhering to the line.
  • When sensor is not fully filled, it can raise end pipeline of flow meter and makes its full
  • The front and rear straight pipes are ≥10DN at the front of the flowmeter and ≥5DN at the back

Flowmeter wiring

  • The remote type signal cable should use a customized dedicated cable.
  • A Yz medium-sized rubber sheathed cable is optional for the excitation cable. Its length is the same as that of the signal
  • Signal cables are strictly separated from other power sources.
  • The signal cable and excitation cable should be as short as possible. The excess cables should not roll. The excess cables should cut off and the joints should be re-welded.
  • When the cable is connected to the electrical interface of the sensor, insert a U-shape at the port. It prevent rainwater from penetrating into the sensor

Flow meter earthing

Electric potential difference is not allowed between measuring sensors and shells. Also converter protection grounding. A separate ground connection is preferred for the electromagnetic flowmeters. If grounding together with other instruments or electrical devices. The leakage current in-ground wire may produce series mode interference to the measurement signal. it could cause the electromagnetic flowmeter can not to work.

  • Measurement sensors must be properly grounded;
  • Earthing wire should not transmit any interference voltage;
  • Grounding wires are not allowed to connect to other electrical equipment.