Vortex flowmeters measure a fluid flow’s velocity. The vortex shedding frequency governs the vortex flow transmitter. A technician compares the output vertex flow frequency with the signal of the input pulse using a calibrator that serves as a master calibrator.
The essential steps in the vortex flow calibration are as follows:
Step 1: Calculating the frequency of vortex shedding as follows:
Frequency of vortex shedding =conversion factor x reference factor x (value of upper range in U.S. gallons/Time).
In this case, the frequency of vortex shedding units is pulse per second or PPS, and the CF, RF, URV values as mentioned on the manual device.
Step 2: Setting 5 checkpoints for spans. A frequency generator is connected to the transmitter’s input signal. The calibrator’s output signal is connected to the transmitter’s signal.
Step 3: Setting the span and making changes as follows:
- The frequency generator is set at the upper range’s value while the fine span screw is adjusted to achieve 100 percent value. The output value is adjusted to zero.
- The frequency generator is disconnected while the signal lead is connected. Adjustment of zero to lower range value is made.
- Match the output and inputs by adjusting zeros
The process is performed for each of the five checkpoints for calibration to be complete.