Phase angle measurement

Phase-angle measuring or otit of step relay Further reading ... 

The power from the amplifier to the Ling vibrator was maintained at 84 watts. The range of frequencies, F, studied was 30 to 100 c.p.s. The resonant frequency for the d2/d — 2 annulus ratio was 37 c.p.s. for the d2/dx = 3, 40 c.p.s. Amplitudes, H, of vibration varied from 0.02 to 0.5 inch. Force and phase angle measurements were made at each test condition, so that power required for vibration could be calculated. 

The results of observations are presented in Table 2, which contains the date of the observations, spectral band (BC 4450/67 ", GC 5256/57 RC 7129/62, V the standard band of UBV-system), phase angle, measured values of polarization degree, position angle, position angle of scattering plane X and planetocentric longitude L of the center of the illuminated and visible part of Mercurian disk. 

The standard phase angle measuring system has been replaced with a lock-in amplifier (Princeton Applied Research Model 5204) to simplify automation of the measurement, to improve resolution of small angles, and to extend the range of tan 6 measurements. 

In Figs. 4 and 5 the results of complex modulus and phase angle measuring as functions of MR concentration are presented. The drop lines indicate the interval of change corresponding parameters for pure LYS. As seen, MR can both increase and decrease the viscoelastic parameters of LYS adsorption layers depending on coneentration. The eflfeet is more expressed at low frequeneies. 

The resistance of membranes can be measured by AC impedance methods [85,86], using the four-point-probe technique. The test membrane is placed in a cell consisting of two Pt-foil electrodes, spaced 3 cm apart, to feed the current to a sample of 3 x 1 cm and two platinum needles placed 1 cm apart, to measure the potential drop (see Fig. 4.3.26). The cell is placed in a vessel maintained at constant temperature by circulating water. The impedance measurements are then carried out at 1-10 kHz using a frequency-response analyzer (e.g., Solatron Model 1255HF frequency analyzer). After ensuring that there are no parasitic processes (from the phase angle measurements, which should be zero), one can measure the resistance directly. The membrane resistance can also be obtained directly from the real part of the impedance (see typical data in Fig. 4.3.27). 

Intuitive interpretation of experiences. One of the direct applications of the relation between the value of the evolution mode and the behavior of energy is that an immediate diagnosis can be made without a computer, by hand, of what happens in the system under study. The phase angle measured by the slope of a Nyquist (Cole-Cole) plot or a Bode plot gives directly the proportion of conserved energy during the process for a given frequency. 

Phase-angle measuring or out-of-step protective relay... 

Kumar S et al. (2012) Phase Angle Measurement in Healthy Human Subjects through Bio-Impedance Analysis. Iranian Journal of Basic Medical Sciences Vol. 15, No. 6, 1180-1184... 

Bode plot A type of frequency response diagram used for analysing the frequency response of a system to a disturbance signal. It is the plot of the logarithm of the amplitude ratio with the logarithm of the phase angle measurements. 

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