Uploaded October 2023 | Updated September 2026, 1 day ago
Ninth part, about the liquid’s dielectric constant sometimes being irrelevant …
↓↓↓ Complete description, time index and links below ↓↓↓
In the eigth video we’ve successfully tested our setup with a reference sensor by measuring the levels of two liquids with vastly different dielectric constants – water and saline (link below). However, at the end I told you there was an oddity.
First we’ll have a look at that oddity and another. Then I attempt to explain them and prove myself wrong. Desperate I measure methanol too before coming up with the correct answer. Finally we verify everything by measuring vegetable oil.
00:00 Intro – oddities in the previous videos’ measurements
00:57 Oddities – dielectric constant irrelevant and thin film effect
03:45 Theory A – incomplete & wrong: only short field lines matter
08:10 Ethanol – measuring another liquid yields identical values
11:13 Theory B – complete & correct: liquid behaving as conductor
18:50 Rapeseed oil – isolating, low dielectric constant liquid
26:37 New physics – unfortunately not, it’s known in the industry
29:38 Wrap-up – there will be one more video, bye
Tutorials youtube.com/playlist?list=PLwq-2MnM58FKn3920rc1V0qoTsQDheTIw
Capacitive Liquid Level Sensing (1): Sensor Basics youtu.be/Jjcym2g2ruk
Capacitive Liquid Level Sensing (2): Measuring Capacity (1) youtu.be/h6ErXsIQWDU
Capacitive Liquid Level Sensing (3): Measuring Capacity (2) youtu.be/v-1B_c-3KQ4
Capacitive Liquid Level Sensing (4): Analog to Digital (1) youtu.be/6-uRvu_0WW8
Capacitive Liquid Level Sensing (5): Analog to Digital (2) youtu.be/BoutyoQyOQI
Capacitive Liquid Level Sensing (6): Analog to Digital (3) youtu.be/g8fjN2WKGN4
Capacitive Liquid Level Sensing (7): Reference Sensor (1) youtu.be/XDtQKoT6Zyo
Capacitive Liquid Level Sensing (8): Reference Sensor (2) youtu.be/pKZHFjDShpM
Capacitive Liquid Level Sensing (10): Errata, Miscellaneous, The End youtu.be/TdAnryA6h-M
My code drive.google.com/drive/folders/1nnl_Gb7OkkYhJTwuc848wvczO3PVb7s3?usp=sharing
Endress+Hauser, Dielectric constant (DC value) Compendium portal.endress.com/wa001/dla/5000894/4733/000/00/CP01076F00EN0114.pdf
Liquid Level Sensing Using Capacitive-to-Digital Converters | Analog Devices analog.com/en/analog-dialogue/articles/liquid-level-sensing-using-cdcs.html
TI Designs: Capacitive-Based Liquid Level Sensing Sensor Reference Design ti.com/lit/pdf/tidu736
#liquid #sensor #capacitance #capacity #capacitor #tutorials #tutorial #how-to #robertssmorgasbord
Ninth part, about the liquid’s dielectric constant sometimes being irrelevant …
↓↓↓ Complete description, time index and links below ↓↓↓
In the eigth video we’ve successfully tested our setup with a reference sensor by measuring the levels of two liquids with vastly different dielectric constants – water and saline (link below). However, at the end I told you there was an oddity.
First we’ll have a look at that oddity and another. Then I attempt to explain them and prove myself wrong. Desperate I measure methanol too before coming up with the correct answer. Finally we verify everything by measuring vegetable oil.
00:00 Intro – oddities in the previous videos’ measurements
00:57 Oddities – dielectric constant irrelevant and thin film effect
03:45 Theory A – incomplete & wrong: only short field lines matter
08:10 Ethanol – measuring another liquid yields identical values
11:13 Theory B – complete & correct: liquid behaving as conductor
18:50 Rapeseed oil – isolating, low dielectric constant liquid
26:37 New physics – unfortunately not, it’s known in the industry
29:38 Wrap-up – there will be one more video, bye
Tutorials youtube.com/playlist?list=PLwq-2MnM58FKn3920rc1V0qoTsQDheTIw
Capacitive Liquid Level Sensing (1): Sensor Basics youtu.be/Jjcym2g2ruk
Capacitive Liquid Level Sensing (2): Measuring Capacity (1) youtu.be/h6ErXsIQWDU
Capacitive Liquid Level Sensing (3): Measuring Capacity (2) youtu.be/v-1B_c-3KQ4
Capacitive Liquid Level Sensing (4): Analog to Digital (1) youtu.be/6-uRvu_0WW8
Capacitive Liquid Level Sensing (5): Analog to Digital (2) youtu.be/BoutyoQyOQI
Capacitive Liquid Level Sensing (6): Analog to Digital (3) youtu.be/g8fjN2WKGN4
Capacitive Liquid Level Sensing (7): Reference Sensor (1) youtu.be/XDtQKoT6Zyo
Capacitive Liquid Level Sensing (8): Reference Sensor (2) youtu.be/pKZHFjDShpM
Capacitive Liquid Level Sensing (10): Errata, Miscellaneous, The End youtu.be/TdAnryA6h-M
My code drive.google.com/drive/folders/1nnl_Gb7OkkYhJTwuc848wvczO3PVb7s3?usp=sharing
Endress+Hauser, Dielectric constant (DC value) Compendium portal.endress.com/wa001/dla/5000894/4733/000/00/CP01076F00EN0114.pdf
Liquid Level Sensing Using Capacitive-to-Digital Converters | Analog Devices analog.com/en/analog-dialogue/articles/liquid-level-sensing-using-cdcs.html
TI Designs: Capacitive-Based Liquid Level Sensing Sensor Reference Design ti.com/lit/pdf/tidu736
#liquid #sensor #capacitance #capacity #capacitor #tutorials #tutorial #how-to #robertssmorgasbord
