Automatic liquid mixing & dispensing using feedback of level & flow measurement

Hello guys,

This is my first post here and I’m really looking forward to receiving some valuable inputs from you guys.

I have been trying to design an automatic fluid dispensing or make-up system for my CNC machine. A Level transmitter will be fitted to my sump and I will use a refractometer to send concentration readings in 4-20 mA to a PLC.

Water & coolant concentrate have to be pre-mixed before being sent to the sump. Water shall be supplied to the dispensing system under gravity & coolant can be transferred from a drum/barrel placed on the ground.

Once everyday, a make-up cycle is required to be run which will use the inputs from the level transmitter & refractometer to decide the quantity of liquid to be topped up.

Since the water will be fed under gravity, can I use a flow control valve with a flow transmitter on that pipeline? And for the coolant concentrate, flow control valve with transmitter on the delivery end of the pump.

Also, I was wondering if I can use a Venturi Injector (Ejector) for mixing the liquids? Or maybe use PWM.

Feel free to let me know if the information given above is inadequate.



Yes, definitely you can use a simple control Valve and a Flow meter.

If process suits then you can use a simple turbine flow meter for your application.

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