This DIY programmable diaphragm pump is ideal for lab use
— July 14th, 2025
If you have to transfer fluid from one vessel to a different, you’re most likely going to desire a pump of some variety. Typical cheap pumps are normally solely on or off, so you possibly can’t simply management the circulation charge. Those who do have some form of analog adjustment are normally imprecise, which is an issue in lab settings. To resolve that drawback on a price range, Marb designed a DIY programmable diaphragm pump unit.
The pump Marb used for this mission is only a 12VDC diaphragm pump you can get anyplace for just a few {dollars}. It solely has two leads: constructive and detrimental energy. Join these to a DC energy supply and the pump will run at a relentless charge. The opposite digital elements that Marb added, all of which match inside a pleasant aluminum enclosure, let the person set a circulation charge with a lot better precision than you’ll get by way of some type of analog management.
This works by adjusting the efficient common voltage to the diaphragm pump’s electrical motor by way of pulse width modulation (PWM). On this case, an Arduino Nano board tells an influence MOSFET module (supposed for 3D printer warmth beds) to modify on and off in a short time. The ratio of “off” to “on” determines the typical voltage and due to this fact the pump motor’s velocity and in the end the circulation charge.
The person can set that velocity by telling the Arduino what PWM worth to make use of. They do this by way of a easy interface consisting of a 16×2 character LCD and a KY-040 rotary encoder.
It’ll take some calibration to seek out out the real-world circulation charges that correspond to the PWM values. However afterwards, this must be exact and correct sufficient for a lot of duties within the lab.
