We received an enquiry from a customer who needed to dose an additive chemical into a main process line, in a fixed ratio, and keep that ratio accurate even as the main flow rate changes. That is exactly what the Contrec 515 AC01 Additive Controller is built for.
It works with volumetric frequency flowmeters on both the main flow and the additive flow, and controls a stroking dosing pump through either an output pulse or a 4-20mA signal. You set the process ratio in PPM (parts per million), and the controller calculates the Target Stroke Rate and the timing for each Stroke Output Pulse based on the dosing pump’s own parameters.
In actual application, it also keeps monitoring the main and additive flow continuously, working out the real Process Ratio and Sample Ratio as it goes, so you get an immediate PPM reading of how much additive is actually going in, not just what was set. Flow and deviation alarms, plus a permissive input, help keep the dosing under control if something drifts out of range.
Before we quote this, we would normally check your dosing pump type and stroke rate, your main and additive flowmeter signals, and the PPM ratio you are targeting.
Hope this helps.
