Search results
Results from the WOW.Com Content Network
In the power systems analysis field of electrical engineering, a per-unit system is the expression of system quantities as fractions of a defined base unit quantity. . Calculations are simplified because quantities expressed as per-unit do not change when they are referred from one side of a transformer to t
They are based on "steady-state (equilibrium) ampacity" calculations. Emergency ratings are based on transient equations and models: they provide permissible overload ratings for a short and adjustable time (typically 5 to 30 minutes). Forecasting methods have been developed to determine intraday and day-ahead ampacity forecasts.
IEC 60853 Calculation of the cyclic and emergency current rating of cables; IEC TR 60854 Methods of measuring the performance of ultrasonic pulse-echo diagnostic equipment; IEC 60855 Live working – Insulating foam-filled tubes and solid rods; IEC 60856 Prerecorded optical reflective video disk system 'Laser vision' 50 Hz/625 lines – PAL
Average power calculation rating depends on some assumptions about how the device is going to be used. For example, the EIA rating method for loudspeakers uses a shaped noise signal that simulates music and allows peak excursion of 6 dB, so an EIA rating of 50 Watts corresponds to 200 Watts peak rating.
The power transformer or battery-to-grid are critical aspects of power distribution and sizing and modelling of batteries or transformers depends on the load profile. [1] The factory specification of transformers for the optimization of load losses versus no-load losses is dependent directly on the characteristics of the load profile that the ...
The test is conducted on the high-voltage (HV) side of the transformer where the low-voltage (LV) side (or the secondary) is short-circuited. A wattmeter is connected to the primary side. An ammeter is connected in series with the primary winding. A voltmeter is optional since the applied voltage is the same as the voltmeter reading.
The burden (load) impedance should not exceed the specified maximum value to avoid the secondary voltage exceeding the limits for the current transformer. The primary current rating of a current transformer should not be exceeded, or the core may enter its non-linear region and ultimately saturate. This would occur near the end of the first ...
Control of solid state loads with transformer isolation: 60947-5-1 AC-14: Control of small electromagnetic loads: 60947-5-1 AC-15: Control of A.C. electromagnetic loads: 60947-5-1 AC-20: Connecting and disconnecting under no-load conditions: 60947-3 AC-21: Switching of resistive loads, including moderate overloads: 60947-3 AC-22