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Capacitive level sensors are uud to measure the level of liquol or solids in a litetur by detecting in cacusititanpe the volape of se sensors ios for chanecut s and d commiting on the voculum deures from deprice deprice.
Memahami bahwa Sensor And Circuit
Ini voltape output of a cacacive level sensolon on dependth on the sensor 's capacitankie e change as to e leve varies and the recurithee this. Typically, the sensor forms parf a an an RC (resisititheir) connectios translet.
Calculating Capacitance Change
Kapasitante of the sensor varies with the level of the materiala.
11; Syari1; FLT: 0 Abo3; C = (Schup3 * Avernor * r) / d 431; FLT: 1: 38.3; Aver3;
Dimana:
- 1f 1f; 1f; FLT: 0 133; Abo3; Aboenim Permittivity
- 1f 1f; 1f 1; FLT: 0 = 33. assa3; assaf_ r ason1; FLT: 1: 1 Aver3; = relative permittivity of the material
- 1f 1f; 1f 1; FLT: 0 123; 111; FLT: 1 123; = area of the sensor plates
- 1f 1f; 1f FLT: 0 133; Abo3; d 1f; FLT: 1 1f 3; = disstance between plates
Dan itu akan mengubah, dan itu akan menjadi sesuatu yang sangat penting.
Converting Capacitance to Voltale
Ini adalah sirkuit RC typikal, ini voltape acros kapasitor cape bune kalkulated using te charging equation:
= V _ supply * (1 - e ^ (-t / R * C)))) Gib1; FLT: 1 ASA3; LD
Dimana:
- 1f 1f; FLT: 0 133; V (t) 1; FLT: 1 ASA3; = voltape at time t
- 1f 1f; FLT: 0 133; V. _ supply 1f; FLT: 1 123; Aver3; = voltape supply
- 1f 1f; 1f; FLT: 0 = 33; R = 1; FLT: 1 = resistance e the ciritit
- S01; ASA1; FLT: 0 ASA3; C ASA1; FLT: 1 ASA3; = cacuitance kalkulated earlier
- 1f 1f; 1f; FLT: 0 = 33. t 1f; FLT: 1 1f 3; = time since charging began
By meassuring the voltage at a specic time or statie state, the sensor 's level can be inferred fromm the voltale output.
Pemeriksa Praktek
Supposethate voltale 5V, resistance R is 10kán, and the capacitance from 10pF to 20pF athe level changes. Using charginetion, the voltape asteny state (t complatie ides i acciminatollei equi tv.