help me with dielectric sensor for testing mango

[mamu_s]

dielectric sensor

helo...I am trying to make dielectric sensor for testing mango. i used parallel plates which same theory as capacitor. at this stage, i just used free air as dielectric to test the parallel plates. It doesn't work. my circuit is only voltage divider with low resistor and ac signal. I gave 5Vp. Area plate, A=0.0025m2 and distance, d= 0.0025m. It my pleasure, if somebody can give me any suggestions. thanks

 

[kender]

Re: dielectric sensor

It doesn't work.

Could you give us more details. What were your expected observations? What are your actual observations?

 

[fsahmed]

Re: dielectric sensor

Take a test mango, check the capacitance using an LCR meter, with the mango and without the mango... if it works, note the change in capacitance and build a bridge circuit in accordance to the change.

 

[rikie_rizza]

dielectric sensor

what metal is the plate made of?

 

[kender]

Re: dielectric sensor

what metal is the plate made of?

Do you suspect that the plate reacts with the mango and produces an electrochamical current? It may happen. But I think, AC excitation and AC coupling the output should remove the problems caused by electrochemical effects.