Flowline DL10-01 EchoPod Ultrasonic Level Transmitter, GP ultrasonic Level Sensor, 1″ NPT, 4-20 mA, with Fob

These level sensors are easy to program and have worked well for us. You need to buy at least one of the USB programming fobs, and this one came with a fob. I bought another one of these sensors elsewhere without the fob since we needed only one fob to program multiple sensors.We've been running these for six months or so, and I've only experienced one glitch. One of them began putting out a noisy and erratic signal. Tracing everything in the loop, it came down to the level sensor itself. I was afraid it had gone bad, but disconnecting it and then reconnecting it so that it had to do a "reboot" fixed it, and it's been running for a week or so without issue.We did buy a spare to have on hand in case one of these does experience a "hard failure".We're using these to tell a PLC what the water levels are in some water treatment plant filters. The PLC then controls the speeds of the effluent pumps for the filters or the positions of the effluent valves (if we're running filter-to-waste). The PLC is set up to run PID algorithms to control the valves and pump motor VFDs.For the price, they're pretty amazing, with resolution that is probably better than we really need for this application.