Digital gas flow meter with 4-20mA output

Gas flow meters needs signal transmission

With the progress of modern industry, field gas flow measuring instruments with only local display can no longer meet the development of various industries. With the development of PLC, DCS and other industry systems, gas flowmeters have added the function of remote transmission signals, generally with 4-20mA signal output to access the control system.

Why choose 4-20mA for gas flow meter signal?

• 1. The flowmeter voltage signal is unstable, it is easily disturbed during long-distance transmission, and however the current signal is relatively stable. The current signal is selected during transmission; while the voltage signal is selected for detailed control in DCS system.
• 2. The signal with a range of 0~20mA cannot be distinguished from the fault signal. Less than 4 mA indicates that the line is faulty, or there is a possibility of zero drift. The birth of the two-wire system gas measuring instrument promoted the revision of the specification, and the new specification of the current signal was set at 4-20 mA.
• 3. 4-20mA is set for the two-wire gas flow sensor. The current of 0-4mA is for small flow measurement. If 0-20mA is selected, when the gas flow signal is small, the gas flowmeter sensor will not be accurate.

In fact, regarding the 4-20 mA signal, the DCS system usually counts more than 20.2 mA and less than 3.8 mA as a fault signal.

In summary, the 4-20 mA current signals have been used as a standard configuration in the instrument industry, facilitating automated production in all industries. In the process of new construction or replacement, it facilitates and simplifies the procedure to maximize benefits. .

The gas flow meter provided by Silver Automation Instrument has 4-20Ma output

For example, the gas flowmeter, the vortex gas flowmeter, the turbine gas flowmeter, the rotor gas flowmeter, etc., all have a 4-20ma output.