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Live testing. Earth fault loop impedance testing: this test is to check that if a fault did occur, that the system meets requirements to cause a disconnection of the supply within the time limit specified by standards Insulation resistance testing Polarity test: a test to check that the connections are connected in the right sequence
[1] [2] In the case of two windings wound around the same core in parallel, for example, the polarity will be the same on the same ends: A sudden (instantaneous) current in the first coil will induce a voltage opposing the sudden increase in the first and also in the second coil, because the magnetic field produced by the current in the first ...
to test series and interpoles (commutating) fields from a DC motor; to determine phasing and polarity in multiwinding armatures; to test rotors in rotating frequency changers, as well as in wound rotors; to test shorts between turns in taped coils before installation into an armature or a stator; as a low voltage isolation transformer
The polarity index is a measure of the polarity of the solute-solvent interactions. It depends strongly on the organic solvent, and somewhat on the polar groups present in the stationary phase. 23 compounds were analyzed with varying mobile phases and compared to the lipophilicity and polarity indices.
Modifying the polarity of a weakly ionic group (e.g. carboxyl) on the surface is easily accomplished by adjusting the pH to be within two pH units of that group's pKa. For strongly ionic functional groups of the surface (i.e. sulfates or phosphates) one could instead use a lower amount of buffer so the residual charge is not completely ion paired.
Saturate, Aromatic, Resin and Asphaltene (SARA) is an analysis method that divides crude oil components according to their polarizability and polarity. The saturate fraction consists of nonpolar material including linear, branched, and cyclic saturated hydrocarbons ( paraffins ).
There are several types of electrical currents used in magnetic particle inspection. For a proper current to be selected one needs to consider the part geometry, material, the type of discontinuity one is seeking, and how far the magnetic field needs to penetrate into the part.
Time-of-flight diffraction (TOFD) method of ultrasonic testing is a sensitive and accurate method for the nondestructive testing of welds for defects. TOFD originated from tip diffraction techniques which were first published by Silk and Liddington [1] in 1975 which paved the way for TOFD. Later works on this technique are given in a number of ...