Tests dissipation factor

This is a resin-rich system. The stator is wound with pre-formed coils on similar lines as noted above. After thorough testing on each coil for the polarization index and dissipation factor (tan S), as discussed in Sections 9.5 and 9.6, and the impulse voltage withstand test, as discussed in Section 11.4.9, the individual coils are completely cured and toughened before inserting them into the slots. The rest of the process is as noted earlier. 

The result of the dielectric testing on these polymers was quite encouraging. All of the polymers that were tested demonstrated low dielectric constant and dissipation factor values. 

BS 7663, 1993. Methods of test for determination of permittivity and dissipation factor of electrical insulating material in sheet or tubular form. 

ASTM D1531, 2001. Standard test methods for relative permittivity (dielectric constant) and dissipation factor by fluid displacement procedures. 

Dielectric test methods are used to measure the cure of epoxy adhesives between two conducting electrodes. This method is especially appropriate for metal-to-metal joints because the substrates themselves can be used as the electrode. The adhesive is treated as a capacitor during the test. Its response (dielectric constant, dissipation factor, etc.) over a range of electrical frequencies is measured as a function of curing time. 

Figure 8 shows a set of load-displacement curves for HM5411EA tested at 1 mm/s. Following the EWF procedure, the plot of the specific work of fracture, uy vs. ligament length, / is produced (Fig.9). It can be seen that linear approximation fits the data very well. From the Intercept between the fitted line and the y-axes, the value of 25.18 kJ/m is obtained for the essential work of fracture. This value represents fracture toughness under plane stress conditions. The slope of the linear fit represents the plastic work dissipation factor, Pwp, where is a shape factor associated with the shape and size of the plastic zone, and Wp is the plastic work dissipation per unit volume of material. The values of fiwp for all cases are given in Table 1.

Constant, dissipation factor dielectric strength. A literature search indicated that little work of this nature has been done with expl materials. Further, such electrical measurements can be used as supplementary criteria for evaluating the purity, homogeneity and, with the exception of the dielectric strength determination, as possible nondestructive tests of expls. Hence the data listed in the following table were deed at Pic Arsn (Ref 2) for the common readily avail expls which are believed to be of interest in research... 

ASTM D 1673-79 (1989) Standard Test Methods for Relative Permittivity and Dissipation Factor of Expcmded Cellular Plastics Used for Electrical Insulation, 5 pp (Conun D-9)... 

Table V Indicates the good retention of electrical properties exhibited by the 40% glass-filled PPS at temperatures up to 147°C. In addition, exposure of test specimens to 50 per cent relative humidity for 5 days did not cause any appreciable change In either dielectric constant or dissipation factor. Thus, environmental factors do not have much effect upon the electrical behavior of polyphenylene sulfide resins.

Electrical Properties. The electrical properties of silicone gels are essentially the same as those of most clean, unfilled silicone elastomers and fluids. Typical values for dielectric constant and dissipation factor when tested at 25°C and 100 Hz are 2.7 to 2.9 and 0.001 to 0.002 respectively. Volume resistivity values, usually, fall in the 10 ohm- centimeter range. 

Dissipation factor (also known as "power factor" or "loss tangent") in electrical tests. Mechanical loss tangent under the uniaxial tension mode of deformation. 

Insert the test piece between the electrodes. Record the values of capaeitance and dissipation factor as C and Record the eell temperature to 0.1 C. 

Remove the test piece from the cell and fill the cell with the fluid chosen. Measure the capacitance and dissipation factor and record the values as Cj and /)v Insert the test piece into the cell. Measure the capacitance and dissipation factor and record the values as C4 and D4. Remove the specimen from the cell immediately after this measurement. 

Rheovibron (dynamic) viscometer is widely used for measurements of dynamic mechanical properties such as loss modulus, storage modulus, and dissipation factor, each as a function of temperature. In this instrument, the test specimen is clamped between strain gauges and subjected to low order of sinusoidal strain at a specified frequency. The value of tan d is directly read and the storage and loss moduli are calculated using sample dimensions and instrument readings. 

Dielectric constant Dissipation factor Sequential-environment tests... 

The main electrical properties related to organic materials are volume resistivity (for both conductive and nonconductive adhesives) and dielectric constant and dissipation factor (for insulative materials). Other electrical tests for conductive materials that are more application specific are electrical stability, current-carrying capacity, and interconnect resistance. 

As for dielectric constant, test methods for dissipation factor may also be found in ASTM D150. ... 

ASTM D150 Standard Test Methods for AC Loss Characteristics and Permittivity (Dielectric Constant) of Solid Electrical Insulation includes the determination of relative permittivity, dissipation factor, loss index, power factor, phase angle, and loss angle through specimens of solid electrical insulating materials when the standards used are lumped impedances. The frequency range that can be covered extends from less than 1 Hz to several hundred megahertz. 

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