S-30-Delta-Standards

00000BLOCK DIAGRAMDELTASTANDARDactual capacitance of these strays is approximately 10 to20 wufd.No effort is made to standardize this value.Asthe switch is rotated,capacitors are switched into the cir-cuit to provide a change (or "Delta")of capacitance as in-dicated.In the 0 uufd position,an additional 3 uufd hasbeen added in addition to the strays.S-30 DELA STANDARDSNOTELater models of the Type S-30 have the capaci-tance ranges marked in picofarads.Since onepicofarad equals one micromicrofarad the actualvalue of capacitance selected remains unchanged.Calibration of Capacitance RangesCalibration of the capacitance ranges is possible withmost commercial bridges.The procedure is to measure thecapacitance of the S-30 in the -3 uufd position,then switchto the 0 uufd position and determine if the "Delta"changeis 3 uufd 1%.Adjustment of C-2 will be necessary if not1within tolerance.Continue to switch to each range andmeasure the capacitance,adjusting the trimmer as indicatedin Table I to give the correct"Delta"changes.TABLE ISwitch PositionTypical ValueAdjustmentFig.6-1.The $-30 Delta Standards.-3 uufd13 uufdNone04μfd16 uufdC-2The S-30 Delta Standards provides a means for calibrat-ing the Type 130 L-C Meter.The accuracy of the S-30 is+3 mufd194μfdC-4+10μfd26 uufdC-61%or better in all ranges.+30μfd46 mufdC.7The S-30 provides seven calibrated capacitance ranges,+1004ufd116fdC-9two precision resistors,and one standard inductance of 300+3004μtfd316 pufdC-11uh at 140 kc.Equipment Required for Calibration of DeltaCalibration of Resistance RangesStandardsTwo precision resistors of identical manufacture are usedA commerical impedance bridge with tolerances ofto standardize the resistance compensation.These can beone quarter of one per cent for capacitance,and one perchecked for resistance value with any reliable bridge.Ifcent for inductance.either resistor is out of tolerance,it is advisable to changeInductance Standardizer,to be constructed from the fol-both to maintain the balance of capacity,unless a resistorlowing specifications in the circuit diagram preceding allof similar manufacture is available.sections on the $-30 Delta Standards.The value of thecapacitor and resistor must be within 2%of those shownFigure 6-2 is a pictorial representation of the completedCalibration of Inductance RangesInductance Standardizer.Standardization of the 300 uh inductance is somewhatOperationcomplicated since its value cannot be read directly with a"Bridge"type device.This is due to the fact thot the cir-Only the stray capacitance of the connector and switchcuit has stray capacitance in parallel with the inductanceassembly is in the circuit in the -3 uufd position.Thewhich will give false indications on a bridge due to the6-1Q®1