Volumetric Calculation for metering systems
Calibration columns are an effective way of performing a volumetric calculation on a metering system.
Installed onto the suction line to the chemical metering pump, two isolation valves are required to be installed one to isolate the main inlet line from the tank, the second to isolate the calibration column. The top of the calibration column should be vented back to the storage tank.
1) Fill the calibration column to the top mark, isolate the main inlet from the storage and open the calibration column valve.
2) Switch on the chemical metering pump and draw down for 30 seconds.
3) Switch the pump off. The reading on the right side of the cylinder is a direct readout.
4) Alternatively, observe the volume withdrawn on the ml scale. There are two scales on the cylinder for US Gph and ml. To convert to LPH or GPH use the following formula
LPH = 3.6 x (ml) / Time ( sec)
GPH = 0.951 x (ml) / Time ( sec )