Arrangements for measuring currents or voltages or for indicating presence or sign thereof

GPHYSICS G01Measuring instruments G01RMEASURING ELECTRIC VARIABLES MEASURING MAGNETIC VARIABLES

G01R19/00Arrangements for measuring currents or voltages or for indicating presence or sign thereof

G01R19/0007Frequency selective voltage or current level measuring G01R19/0015separating AC and DC G01R19/0023Measuring currents or voltages from sources with high internal resistance by means of measuring circuits with high input impedance G01R19/003Measuring mean values of current or voltage during a given time interval G01R19/0038Circuits for comparing several input signals and for indicating the result of this comparison G01R19/0046characterised by a specific application or detail not covered by any other subgroup of G01R19/00 G01R19/0053Noise discrimination; Analog sampling; Measuring transients G01R19/0061Measuring currents of particle-beams, currents from electron multipliers, photocurrents, ion currents; Measuring in plasmas G01R19/0069measuring voltage or current standards G01R19/0076using thermionic valves G01R19/0084measuring voltage only G01R19/0092measuring current only G01R19/02Measuring effective values G01R19/03using thermoconverters G01R19/04Measuring peak values or amplitude or envelope of ac or of pulses G01R19/06Measuring real component Measuring reactive component G01R19/08Measuring current density G01R19/10Measuring sum, difference or ratio G01R19/12Measuring rate of change G01R19/14Indicating direction of current Indicating polarity of voltage G01R19/145Indicating the presence of current or voltage G01R19/15Indicating the presence of current G01R19/155Indicating the presence of voltage G01R19/165Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values G01R19/16504characterised by the components employed G01R19/16509using electromagnetic relays G01R19/16514using electronic tubes G01R19/16519using FET's G01R19/16523using diodes G01R19/16528using digital techniques or performing arithmetic operations G01R19/16533characterised by the application G01R19/16538in AC or DC supplies G01R19/16542for batteries G01R19/16547voltage or current in AC supplies G01R19/16552in I.C. power supplies G01R19/16557Logic probes G01R19/16561in hand-held circuit testers G01R19/16566Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533 G01R19/16571comparing AC or DC current with one threshold G01R19/16576comparing DC or AC voltage with one threshold G01R19/1658AC voltage or recurrent signals G01R19/16585for individual pulses, ripple or noise and other applications where timing or duration is of importance G01R19/1659to indicate that the value is within or outside a predetermined range of values (window) G01R19/16595with multi level indication G01R19/17giving an indication of the number of times this occurs G01R19/175Indicating the instants of passage of current or voltage through a given value G01R19/18using conversion of dc into ac G01R19/20using transductors G01R19/22using conversion of ac into dc G01R19/225by means of thermocouples or other heat sensitive elements G01R19/25using digital measurement techniques G01R19/2503for measuring voltage only G01R19/2506Arrangements for conditioning or analysing measured signals G01R19/2509Details concerning sampling, digitizing or waveform capturing G01R19/2513Arrangements for monitoring electric power systems G01R19/2516Modular arrangements for computer based systems; using personal computers (PC's) G01R19/252using analogue/digital converters of the type with conversion of voltage or current into frequency and measuring of this frequency G01R19/255using analogue/digital converters of the type with counting of pulses during a period of time proportional to voltage or current, delivered by a pulse generator with fixed frequency G01R19/257using analogue/digital converters of the type with comparison of different reference values with the value of voltage or current G01R19/28adapted for measuring in circuits having distributed constants G01R19/30Measuring the maximum or the minimum value of current or voltage reached in a time interval G01R19/32Compensating for temperature change