How to measure this capacitance using a capacitance meter

1. Jul 16, 2015

nst.john

I posted this picture in another thread but I now have a specific question for the capactance measurement between both transducers (the middle C). How can I measure the capacitance of this using an LCR meter. Where should the leads be put and what are some averages of a capacitance I should be getting for transducers about 4-5inches apart with a 3 inch diameter apporximately with a glass beaker with water between them? Thank you for your help!

2. Jul 16, 2015

tech99

Two metal plates of the dimensions you mention may give about 30pF with the water dielectric. I suggest joining the two leads of each transducer together. You could also experiment using metal plates. C= 0.088 kA/d (where C is the capacitance in pF, A is the area of one plate in cm2, d is the spacing in cm and k is the relative permittivity of the dielectric, about 81 for water).

3. Jul 16, 2015

nst.john

Sounds like a plan. Thanks so much for the help