R1.7 PULSE LOADS In many applications the resistor will be subjected to pulse loads. We make distinctions between periodical/repetitive loads and pulse trains; on one hand, where the pulse is repeated at a certain frequency, and on the other separate pulses where a possible repetition will occur after so long time that the resistor has recovered its original ambient temperature. R1.7.1 Periodic pulse loads...
R1.1 RESISTIVITY (ρ) The resistivity, ρ, is a material constant. The higher the resistivity in the resistor material, the higher its resistance. The connection can be described as .............................. HereR = resistancel = conductor lengthA = conductor area. Depending on what units we express l and A in we get different units of ρ. A common way is by expressing l in m(eter) and...
C1.6 CATEGORY CONCEPTS AND DERATING Recommendation for voltage derating means that the actual capacitor shall be used in the application at lower voltage than rated voltage. Derating is expressed usually by percentage of rated voltage that shall be subtracted. For example 20% derating means that the capacitor shall be used at 80% of rated voltage at the specific applications (10V capacitor to be used...
C 1.5. Ripple Current and Power Load Capacitors are naturally limited by its capability to handle/dissipate ripple current and pulse energy load. The limitation may be significantly different by each capacitor technology but also within a specific product type individual series. In general, the impact of inrush and ripple current can be divided to three time zones: high current immediate surge spiketransient load dI/dt...
C1.4 ENERGY CONTENTS / FORCE MANIFESTATIONS C 1.4.1 Energy contents The energy stored in a capacitor can be described as …………… C 1.4.2 Force action from electromagnetic fields Parallel current carrying conductors are surrounded by magnetic fields exerting forces on each other. If currents flow in the same direction the fields (and the conductors) attract each other. If the current flows in opposite directions...
