Title :
Highly sensitive humidity sensor for dielectric measurement (water absorption) in glass-fiber resins
Author :
Matko, V. ; Donlagic, D.
Author_Institution :
Fac. of Electr. Eng. & Comput. Sci., Maribor Univ., Slovenia
Abstract :
The humidity sensor using the sensitive capacitive-dependent crystal is described. Presented is the probe sensitivity (dependence of df on the dCx). In addition, the new idea of excitation of the entire humidity sensor with stochastic test signals is described, and the humidity surface-measuring method is given. It includes the influence of test signals on the weighting function uncertainty and on the A/D-D/A conversion. The results of the air-humidity measurement and water absorption measurement in glass-fiber resins are shown experimentally. The uncertainty of the surface humidity measurement is less than 0.2% (T=15-25°C and air-humidity=50 to 98%)
Keywords :
atmospheric humidity; correlation methods; dielectric measurement; digital instrumentation; glass fibre reinforced plastics; humidity sensors; sorption; stochastic systems; water; 15 to 25 C; A/D-D/A conversion; H2O; air-humidity measurement; dielectric measurement; excitation; glass-fiber resins; humidity sensor; humidity surface measurement; probe sensitivity; sensitive capacitive-dependent crystal; stochastic test signals; water absorption; water absorption measurement; weighting function uncertainty; Absorption; Autocorrelation; Capacitance; Capacitive sensors; Capacitors; Dielectric measurements; Equations; Humidity; Probes; Testing;
Conference_Titel :
Instrumentation and Measurement Technology Conference, 1998. IMTC/98. Conference Proceedings. IEEE
Conference_Location :
St. Paul, MN
Print_ISBN :
0-7803-4797-8
DOI :
10.1109/IMTC.1998.676881
