What does a potentiometer do?

Alicat-O-Lantern full mass flow

Alicat-O-Lantern at full mass flow of 500 sccm

What does a potentiometer do?

To answer this question–“What does a potentiometer do?”–we needed a visible way to demonstrate the ease of use of a potentiometer, or “pot,” and our IPC in particular. Being so close to Halloween, we also wanted to make use of a pumpkin in some way. My colleague Jesse mentioned our burner control application, which would beautifully demonstrate the flow rate increasing and decreasing by the brightness of the flame. Combine this with a pumpkin, and you have the Alicat-O’-Lantern!

I carved Alicat’s logo into a large pumpkin over the weekend and tested it with a tealight candle. Success! Now we needed to add burner control via our IPC-equipped mass flow controller. So, I bought the smallest bunsen burner I could find, a mere 2-1/2 inches tall. Attaching a small canister of propane provided the fuel for the burner. I placed a MC-series mass flow controller between the propane source and the burner to provide precise flow control. This controller has a range of 500 sccm and is equipped with our IPC and a color backlit TFT display–perfect for a nighttime video shoot!

Alicat-O-Lantern mass flow demonstration

At lunchtime, we set up the components for our video answer, but there was a problem: propane burns blue. The photo at left shows the blue flame burning in the pumpkin. You could see it, but we needed more impact. Then we found a solution: use a camping lantern mantle around the bunsen burner. We tested a small mantle, and the yellow flame was gorgeous! Then we tested a longer mantle that we suspended from the lid of the pumpkin. The brightness was astounding. We had found our answer.

Alicat-O-Lantern gas select menu

Alicat-O-Lantern, showing Gas Select menu
(and propane now selected!)

Alicat was abuzz as dusk approached. It was time to start filming. A few kind souls stayed after hours to help me make this shoot a success, including Marcus, whose hand is turning the IPC in the daylight shot. We filmed the Alicat-O’-Lantern as the setting sun was bathing the mountains in pink and purple hues of light. It was beautiful, and the shoot was a success…after I changed the Gas Select from air to propane! (“The best laid plans of mice and men often go astray!”) I love the sound that the gas makes inside the pumpkin when it is fully lit at a flow rate of 500 sccm!

The Alicat-O’-Lantern shows how easy it is to change your setpoint using a “pot” like the one in our Integrated Potentiometer Control. Just like turning up the volume on your car stereo, you simply turn up the flow rate for your mass flow controller or pressure controller. But the video also shows how much fun we have at Alicat. We truly enjoy solving problems, and we hope you will give us a chance to solve yours!