Measuring fuel level

[makki]

.. but robust.

Well, also thought that, two dead in 4 years.. Let's try these..

Makki

[Warichet]

Maxbotix's TechSup is quite helpfull (unlike another sensor manufacturer... )
Their recommendation for tank management:

The sensor that works best for tank level measurement in the HRXL-MaxSonar-WR line is the MB7369 or MB7389. The difference between the 2 is the serial output. The MB7369 has an RS232 serial output, while the MB7389 outputs data in a TTL serial format. You can click this link to view our tank test.

Pointer to a test
But ... the price is quite different, 105$ instead of 35$ for my low cost thing.

Forgot to mention ... the "F-option" is recommended for fuel tank, hence an additional 40$, sooo 145$ total

[makki]

I'm fed up and neither have the time nor fun on trying, so I'll order the Tecson (for any "virgin"-reader: this story goes on for some years now!)

Will share my results

Makki

[Warichet]

I'll order the Tecson

Why not the Elsner Elektronik, ELS 70151 KNX SO250, 456€ (sensor and converter)

It would be interesting to know what type of sensor they are using ;-)

[makki]

The Elsner is US, I'd still prefer a pressure-based one (if it's then working for more than 6 months ))
US was/is already in place, some pages above, for 1/10th of the cost but it's nasty to mount and operate - with alle the stuff hanging around in my zisterne..

Makki

[Warichet]

After almost a month of fiddling and testing the ultrasonic sensor, I noticed that the output of the sensor is not consistent.
To be noted that the sensor has been tested in an office environment (not in the tank) and was quite reliable.

The cause of the trouble has to be found "outside" the sensor itself. A fellow member hinted me to "disturbances" of the sonic part of the sensor, mainly the noise of the fuel pump and the noise of the fuel return flow back to the tank. This might be an explantion why some readings are higher than the previous (without tank refill of course).

My personal conclusion:
Ultrasonic sensors are inappropriate for fuel level monitoring. Although, they might be fine for water level monitoring.

I'll order the Tecson

I'll do the same. Any reference, please ?
Thanks

[anlo007]

just as a remark in that question:
my Prognitz-Sonde is still working very accurate in the oil-tank... nearly 3 years now.

[Warichet]

my Prognitz-Sonde is still working very accurate in the oil-tank... nearly 3 years now.

Nice to know it works for you.
I've also a Prignitz sensor (based on the pressure difference, not sonic), for my water pit.
It's defective since a year https://knx-user-forum.de/images/icons/icon8.gif and Prignitz didn't bother to reply to my many mails, so I wan't buy anything from them anymore.https://knx-user-forum.de/images/icons/icon13.gif

[anlo007]

I know, that you were hesitating to put it into fuel, but fuel is easier than water, because it is isolating and there is no conterminations with alga.

But it shows, that the prinzipal of measuring the pressure works quite well over the time. There are certainly others (more friendly) companies, who will supply such equipment. Just as an idea, where to serarch.

I will look up some more suppliers on monday.

[Warichet]

I know, that you were hesitating to put it into fuel

Indeed, and I'm still hesitating, because of the ATEX specifications. That's why I liked the idea of an ultra-sonic sensor.... there is no physical contact with the medium. Let's take an extreme case, with a pressure type sensor, installed in the tank. Instead of feeding it with 24VDC for the current loop, you make a mistake and put 220V to the sensor. This might eventually ignite the fuel (low level fuel, hot external temperature and fuel vapor inside the tank)

it shows, that the prinzipal of measuring the pressure works quite well over the time.

I agree, this is certainly true for small to medium distances, i.e. 3-4m, but I'm questioning distances of 18m like in my water pit. Imho, if it has been sold, it should work or taken back

I will look up some more suppliers on monday.

Thank you for your kind help, much appreciated.

[ur63]

If you are into electronics, you could do your own design of measuring hydrostatic pressure (translates into fluid level...) outside of the fluid. Just use a pipe that sticks into the fluid (down to the bottom) and install the electronics at the top of the pipe, outside of the fluid.

If you calibrate the output signal properly, the signal could be proprtional to the fluid level and simply measured by voltage measurement (eg. 0-5V = 0...5m)

Just a thought starter...

[Warichet]

If you are into electronics

I was ... long ago

you could do your own design of measuring hydrostatic pressure (translates into fluid level...) outside of the fluid. Just use a pipe that sticks into the fluid (down to the bottom) and install the electronics at the top of the pipe, outside of the fluid.

Clever idea, indeed, but beyhond my modest capabilities. Also, I'd prefer a solution based on standard components easy to fix by someone else than me.

[ur63]

I was ... long ago

Clever idea, indeed, but beyhond my modest capabilities. Also, I'd prefer a solution based on standard components easy to fix by someone else than me.

Then look for hydrostatic pressure sensor or fluid level sensor or similar.
There are several companies out there selling that stuff. Tecson was just one example.

[Warichet]

Then look for hydrostatic pressure sensor or fluid level sensor or similar.

OK, thanks.
I would appreciate a reference from a working installation. I'm not specially lazy, but it's sometimes difficult for me to read the german web sites.

[makki]

We went through all the stuff for years now I guess
I'll report if it works - once again..

Makki