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Electromagnetic flowmeter output pulse signal method description

The electromagnetic flowmeter outputs 4~20mA and sends it to the system for display, or enters the secondary meter for display. This signal is used to display the instantaneous flow, but if it is in the system or in the secondary meter, the flow of this point needs to be accumulated. That is the pulse signal. A pulse signal corresponds to a certain flow value and is superimposed in the system to calculate the cumulative flow. These two signals do not interfere with each other.

The electromagnetic flowmeter pulse output mode is mainly used for metering mode, and outputs a pulse, representing an equivalent flow rate, such as 1L or 1M3. Pulse output equivalent: 0.001L, 0.01L, 0.1L, 1L, 0.001 M3, 0.01 M3, 0.1 M3, 1 M3; , 0.001UKG, 0.01UKG, 0.1UKG, 1UKG, 0.001USG, 0.01USG, 0.1USG, 1USG . When selecting the pulse equivalent, the user should pay attention to the flowmeter flow range and pulse equivalent. For the volume flow, the formula is as follows: QL=0.0007854×D2×V (L/S

Or QM=0.0007854×D2×V×10-3(M3/S)

Where D - diameter (mm);

V — flow rate (m/s)

If the flow rate is too large and the pulse equivalent is too small, the pulse output will exceed the upper limit. Therefore, the pulse output frequency should be limited to 2000P/S or less. Of course, the small flow rate and the excessive selection of the pulse equivalent will cause the meter to output a pulse for a long time.

In addition, the pulse output is different from the frequency output, and the pulse output is accumulated by one pulse equivalent to output one pulse, and therefore, the pulse output is not very uniform.

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