Model SR715 Model SR720 LCR Meters

SR715/720 LCR METERSeries and Parallel circuit modelsRs in capacitors is often referred to as ESR orequivalent series resistance. It includes things likedielectric absorption in addition to the ohmic lossesdue to the leads. It is often listed on data sheetsfor electrolytic capacitors used in switching powersupplies. At high frequencies, the ESR is thelimiting factor in the performance of the capacitor.The quality factor, Q, is the ratio of the imaginaryimpedance to the real impedance. For inductors, ahigh Q indicates a more reactively purecomponent. A low Q indicates a nearly pureresistor. Q varies with frequency. Q is commonlyused to describe inductors. With resistors, often allthat is stated is that the resistor has lowinductance.The dissipation factor, D, is equal to 1/Q and is theratio of the real impedance to the imaginaryimpedance. A low D indicates a nearly purecapacitor. D is commonly used when describingcapacitors of all types.ix