Controlling the output of a water pump

Hello,

I want to use the following Peristaltic Liquid Pump with Silicone Tubing:

Motor voltage: 12VDC
Motor current: 200-300mA
Flow rate: up to 100 mL/min

My question is, is there any solution on how to gather feedback of what amount of water does it emits? Ok, the obvious solution is if I open it for 2 min to multiply and calculate (100ml/min) * 2 mins = 200 min. But is there something more accurate?

How I control it? I thought of a ON-OFF relay, but is there any other method?

Thanks...

alex5678:
My question is, is there any solution on how to gather feedback of what amount of water does it emits? Ok, the obvious solution is if I open it for 2 min to multiply and calculate (100ml/min) * 2 mins = 200 min. But is there something more accurate?

I'd be inclined to run it for a while and measure how much water is dispensed. Possibly you may need to account for differences when starting and stopping.

How I control it? I thought of a ON-OFF relay, but is there any other method?

Logic level MOSFET?

Hi,
Your calibration method is what I use for these little pumps. They seem pretty consistent as long as the 12VDC is decently regulated.

I use this for chlorine dosing in my swimming pool: works great. Never any algae or cloudiness as long as free chlorine NEVER goes below 2 ppm. (Photo HERE )

12V at 200 mA is easy. Relay from Arduino, or a power FET with logic level input, like THIS one..

or a relay like THIS one..

DISCLAIMER: Mentioned stuff from my own shop... which is what I know best ...

In cars membrane fuel pumps are sometimes used. As I understand each stroke delvers a certain quantity. Just count the strikes and multiply by the volume of each stroke.
What accurasy do You really need?

There us a device called a flow sensor, you need to chose one that will work with what you are passing through it and will measure in the range you are pumping. Your selection of a Peristaltic Liquid Pump with Silicone Tubing is a great choice. They are used in many applications to meter liquids. The pump which may be the obvious solution is probably the most cost effective solution. Then you only have to monitor the motor rotation, which can be driven with a simple mosfet or consider the uln200x which is available on shields for less then a dollar. There are encoders that can be mounted on the pump to count rotation or fractions there of. The desired accuracy and your budget determines how to measure it. A simple timer may be your best solution!
Good Luck & Have Fun!
Gil

In my experience peristaltic pumps are pretty consistent in volume per time, and work great for dosing fertiliser in my hydroponic system. My runtimes are typically in the tune of 10-200 seconds, for very short runtimes I would expect less accuracy due to starting up of the motor and the way the pumps themselves are constructed: the liquid comes out in pulses. I calibrate the pumps by letting them run for 1 minute and measure the weight of the water that is pumped out.

A way of dosing very small quantities or very low flows accurately is a peristaltic pump run by a stepper motor. That allows for very precise control of how much you rotate the pump, and how much liquid is pushed out.