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Insulation system. The electrical insulation system for wires used in generators, electric motors, transformers, and other wire-wound electrical components is divided into different classes by temperature and temperature rise. The electrical insulation system is sometimes referred to as insulation class or thermal classification.
IEC 60269 unifies the electrical characteristics of fuses that are dimensionally interchangeable with fuses built to earlier British, German, French or Italian standards. [ 2] The standard identifies application categories which classify the time-current characteristic of each type of fuse. The application category is a two-digit code.
Thermodynamic pump testing is a form of pump testing where only the temperature rise, power consumed, and differential pressure need to be measured to find the efficiency of a pump. These measurements are typically made with insertion temperature probes and pressure probes fitted to tapping points on the pump's inlet and outlet. [1]
Operating temperature. An operating temperature is the allowable temperature range of the local ambient environment at which an electrical or mechanical device operates. The device will operate effectively within a specified temperature range which varies based on the device function and application context, and ranges from the minimum ...
Ratings found in centrifugal fan performance tables and curves are based on standard air SCFM. Fan manufacturers define standard air as clean, dry air with a density of 0.075 pounds mass per cubic foot (1.2 kg/m 3 ), with the barometric pressure at sea level of 29.92 inches of mercury (101.325 kPa) and a temperature of 70 °F (21 °C).
Theoretical temperature rise is: [29] = () / with T 1 and T 2 in degrees Rankine or kelvins, p 2 and p 1 being absolute pressures and = ratio of specific heats (approximately 1.4 for air). The rise in air and temperature ratio means compression does not follow a simple pressure to volume ratio.
IEC TR 60943 Guidance concerning the permissible temperature rise for parts of electrical equipment, in particular for terminals; IEC 60944 Guide for the maintenance of silicone transformer liquids; IEC 60945 Maritime navigation and radiocommunication equipment and systems – General requirements – Methods of testing and required test results
Motor velocity constant, back EMF constant. is the motor velocity, or motor speed, [ 2] constant (not to be confused with kV, the symbol for kilovolt ), measured in revolutions per minute (RPM) per volt or radians per volt second, rad/V·s: [ 3] The rating of a brushless motor is the ratio of the motor's unloaded rotational speed (measured in ...