Liquid Level Transmitter, Waterproof 5m Cable 12‑32VDC 4‑20mA Water Level Transducer, Liquid Level Sensor Detector(0-4m)

I've got about 3 weeks testing in water and about 3 weeks in a fuel oil tank and here are some things I have learned:1. The documentation sucks, but if you follow what another reviewer put here for a schematic, you will not have any problems.2. Isolate your two power supplies. If you don't you will smoke your 4-20mA to 0-5v converter. Also mentioned by another reviewer. I used two wall warts, ungrounded. I tied the shielding on the twisted pair and the sensor together and let that float.3. It is very noisy (regardless of the shielding configuration) so plan to use either a running average or kalman filter for data smoothing.3. VERY important-and not mentioned anywhere I noticed. DO NOT use a compression gland to seal or strain relieve the cable. There is a plastic capillary tube inside that provides an atmospheirc pressure balancing (unless you are making a barometer). First image included with this review is historical barometric pressure juxtaposed against my data. Second image shows how long it takes for the capillary to collapse and start being a barometer.Good luck. I would have given 5-stars if not for #1 above. There is no good reason for the marginal documentation.Edit: if you're trying to make a 0-1m level sensor look at the ST VL53L0X laser tof. Ultimately simpler (hardware wise) cheaper and more accurate. I'm running both for now to see which is more reliable. I found ultrasonic completely unreliable.

This product did exactly what it promised. I have had it installed for a few weeks now with no problems. The reason for the four stars is the documentation is terrible. I was an instrument/automation engineer for almost 45 years (certified by ISA in fact) so I understand 4-20 mA loop powered devices, how they are used, and what to watch out for. Someone without that experience would struggle to figure out how do I get a voltage out of this thing, and then because they specify the power supply needed with zero resistive load, might pick an in appropriate power supply and wonder why is this not working with a dropping resistor? A few diagrams and some text would really help the average home automation devotee. But they are none existent.

Seems to work as a expected. At a depth of 0 meters, the current is 3.6mA (with a 400 Ohm bias resistor). At a depth of 2 meters, the current is 8 mA. This suggests that I have a 5 meter version.I plotted current vs. depth for 5 data points. The transfer function is fairly linear, but not exactly. Good enough for my application.

Buena calidad. Recomiendo hacer pruebas antes de usarlo, para verificar valores.

It doesn’t give me right level of the water tank.