Signal Conditioning, 1 AC/DC/ground coupling | Fluke PM-3394B

USING THE COMBISCOPE INSTRUMENTS

3 - 39

3.7 Signal Conditioning

The INPut subsystem allows you to condition the input signals, such as AC/DC/GROund coupling, input filtering, and input impedance selection.

In the digital mode, the SENSe:VOLTage<n>:RANGe:AUTO command allows you to enable autoranging of the attenuation for each of the input channels <n> separately.

@1

@2

@3

@4

	INPut	SENSe
			:FUNCtion
	INPut[1]	:VOLTage[1]	:OFF
	INPut[1]	:VOLTage[1]	"XTIMe:VOLTage1"
			"XTIMe:VOLTage1"
			[:ON]
	INPut2	:VOLTage2	:OFF
	INPut2	:VOLTage2	"XTIMe:VOLTage2"
			[:ON]
			:SWEep
	INPut3	:VOLTage3	:OFF
	INPut3	:VOLTage3	"XTIMe:VOLTage3"
			[:ON]
	INPut4	:VOLTage4	:OFF
	INPut4	:VOLTage4	"XTIMe:VOLTage4"
			[:ON]
			Main Time Base
			ST7159

Figure 3.15 Signal conditioning

3.7.1AC/DC/ground coupling

The INPut<n>:COUPling command allows you to set the vertical input coupling at AC, DC, or GROund for each input channel separately. After a *RST command, all input channels are DC coupled.

PROGRAM EXAMPLE:

CALL	Send(0,	8,	"INPut:COUPling AC", 1)	’Sets channel 1 AC coupled
CALL	Send(0,	8,	"INPut2:COUPling GROund", 1)	’Sets channel 2 ground coupled

Image 58

Fluke PM-3394B, PM-3380B, PM-3390B, PM-3370B, PM-3384B user manual Signal Conditioning, 1 AC/DC/ground coupling

Contents

Qvwuxphqw Trademarks About this Manual What this Manual Contains IIIInitializing the CombiScope Instrument Measuring Signal Characteristics 15.1.1 15.4.2 Error-reporting using the SRQ mechanismReadout of measurement data 15.1.2 Command Reference Application Program Examples . . . . . . . . . . . . . A-1 VII What this Manual Contains About this Manual About this Manual Getting Started with Scpi Programming System setupPreparations for Scpi Programming Programming environment Addresslist CommandCommands Constant -1 Ffff hex Program Example Programming Note How to switch between digital and analog mode How to reset the CombiScope instrumentHow to identify the CombiScope instrument Initializing the CombiScope Instrument Error Reporting ’Requests for error Format of the trace response data is as follows Acquiring TracesChannels and memory registers Example Send -- FORMat INT,16 Example Preparations How to acquire a single shot traceThis string data How to acquire repetitive traces Connect a probe from the Probe Adjust signal to channel MEASure? Measuring Signal CharacteristicsCONFigure + READ? INITiate + FETCh? How to make a single shot measurement How to make repeated measurements Using the Combiscope Instruments Introduction Using the Combiscope Instruments SAV Fundamental Programming ConceptsTRACe? CH1 RCL SYSTemKEY DISPlayMENU TRIGgerMeasurement instructions Single function programming using the instrument model Explanation of the Instrument Model Instrument setup Read ← blockdata Instrument setup Front panel simulation MEASure? query MEASureAC? Voltageparameters = expectedvoltage,resolution Benefits of using parametersGeneric form of a measurement instruction is as follows MEASureVOLTageAMPLitude? 10, @2 ExamplesMEASureAMPLitude? MEASureVOLTageFREQuency? 10E6, @3 Pulse characteristics Waveform measurements Measurefunctionmeasureparameters MEASureFALLTIME? @3MEASureRISETIME? 20,80 FTIMe = alias for Falltime RTIMe = alias for Risetime SENSeAVERage on Customizing settingsCONFigureAC SENSeAVERageCOUNT READRISEOVERshoot? CONFigureRISETIMEMultiple measurements Starts Acquisition Returns Multiple characteristics from a single acquisitionREADFREQuency? Starts a Next acquisition Returns New Frequency result INITiate Trigger control via GpibTRIGgerSOURce BUS FETChAC? Fetching characteristics from memory traces M12,CH2 Acquisition Acquisition control Using the Combiscope Instruments Trigger Source TriggeringTrigger Type Trigger Level Trigger Slope Trigger Coupling DC Coupling DC Coupling 0 Hz cutoff frequencyAC Coupling 10 Hz cutoff frequency HF-REJECT 30 KHz cutoff frequency LF-REJECT 30 KHz cutoff frequencyVideo triggering PAL NtscLines per frame Secam Line Trigger modesOFF BUS Commands State Description Pre- and post-triggering Trace External triggering Reading trace acquisitions 10 The trace acquisition flow Single-shot acquisition Repetitive acquisitions Conversion of trace data 11 Relation between screen position and trace value ’Array of 512 integers Byte1 = ASCMID$response$, J For 8-bit sample traces Ps = TsPs = Ts / 25600 * 100 = Ts Using the Combiscope Instruments Program Example ’1-byte samples Averaging Acquisition Data AVGn = ∑X1 + .. + Xn ⁄ n 13 The Trigger Model during acquisition averaging Channel Selection Programming tip Signal Conditioning 1 AC/DC/ground coupling Input polarity Input filteringInput impedance Vertical range and offset Autoranging attenuators Vs = Ts / 200 * PTPeak OFFSetLimitation Time base speed Time Base ControlNumber of samples MTB = 50 * SENSeSWEepTIME / TRACePOINts Ts = sampleindex * SENSeSWEepTIME / TRACePOINts Real time acquisition 16 Definition of a signal period Autoranging time base Select the source for the post processing function How to do post processingPost Processing Send → CALCulateFEED M21 ’M21 = source for CALC1 Math Standard AvailableMathematical calculations Optional Example Send → TRACe? M21 Check the result of the post processing functionRead ← tracebuffer ’Reads M21 trace Mathematical calculations Differentiating and integrating traces Relative FFT Frequency domain transformationsAbsolute FFT For 16-bit samples Ps = Ts 25600 Trace Point ValuesTrace data Example for attenuator setting 0.5 V/div This can be calculated as a signal levelVrms offset calculation DBμV offset calculation DBm 50Ω offset calculationDBm 600Ω offset calculation DBμV = 1 μV 1.0E-6 V at 50Ω impedance Trace Point Frequencies SettingFs = sampleindex * 1250 / TRACePOINts * MTB Program Example Amplitude belt = peak-to-peak range Histogram functionsFrequency filtering Trace Memory 20 Trace memory control Extended Channels Memory Registers StandardPM33x0B 512 +EXT Trace formatting Copying traces to memory ’Queries for CH3 trace Writing data to trace memorySend → TRACe? CH3 Read ← trace block Reading data from trace memory Display functions Screen/Display FunctionsBrightness control Menu Meastype,measvalue,suffixunit Measurement ValueMEAS1/MEAS2 Data Description Type Unit Description Cursors DataMath FFT Data Call Send0, 8, DISPlayMENU MEASure Program Example 2 text as block data Display of user-defined textSelection of softkey menus Hpgl Print/Plot FunctionsDevice Type Hplaser 22 Hardcopy of screen on printer/plotter Real-Time Clock Auto Calibration = okay Status Reporting Status data for the CombiScope instruments CALibrating Digital modeOperation status data RANGing VOLTage TEMPeratureQuestionable status data CALibration How to reset the status data Status Register Data Structure Preset Value How to enable status reporting Program example using the status byte STB ’Defines SRQ-routine How to report errors Error-reporting routine ’Sends error query How to save/restore a setup via instrument memory Saving/Restoring Instrument SetupsHow to restore initial settings How to save/restore a setup via the Gpib controller Row 201 How to simulate the pressing of a front panel keyFront Panel Simulation Row 801 How to simulate the operation of a softkey menu Autoset Simulation DISPlayMENU ACQuireSYSTemKEY 3 toggles on/off Functions not Directly ProgrammableEnvelope MULTiple-shot Non-terminal symbols Syntax specification notationsMeta symbols Terminal symbols Between the square brackets, without DefaultNot contain the message element MEASureVOLTageDC? is the same An explicit decimal point and may or may not be Data typesPreceded by a sign, e.g Examples This is a string Bit codesDouble quotes ’This also’ Command Summary Feed Gate State Command Reference ParametersMenu Name DATA? Read TYPE? Auto Baud DTRRTS Bits ALL Type PAL Secam Ntsc Hdtv Measurefunction Measureparameters Expectedvoltage ,resolutionTimeresolution Referencelow ,referencehigh,expectedtime Command Descriptions Front panel compliance ErrorsSpecifies the compliance with front panel operations Calibration okay Calibration not okay CAL? CALibrationSyntax *CAL? Response 0 Limitation 16COMMAND Reference Clear Status Ation Complete bits to be summarized in the Status Event Status EnableByte Register. Alternative commands *ESE #B10001 *ESE #H11 Response Integer Description 18COMMAND ReferenceEvent Status Register PON URQ CME EXE DDE QYE RQC OPC ESR IDN? Identification Syntax *IDN? Query form *OPC? Response Description 20COMMAND ReferenceOperation Complete Restrictions OPT? Option identification Ieee EXT EM MP 22COMMAND Reference Recall instrument setupSyntax RCL numericdata Description Function Default Settings RST ResetSyntax *RST Description Math 1 Beeper Hardcopy Print & Plot Plotter Hpgl Pass/Fail testingMeasure 1 Cursors Save instrument setup Syntax SAV numericdata Description 26COMMAND Reference Service Request EnableRequest Enable Register STB? Status Byte Syntax STB? Response Integer Description TRG Trigger Syntax *TRG Description Syntax *TST? Response 0 TST? Self-testSelf-test okay Self-test not okay Command Reference Syntax ABORt Description Configures for AC-RMS valueABORt Aborts the current acquisition CALCulatenDERivativePOINts CALCulatenDERivativeSTATe Switches the differentiateFunction on CALCulatenFEED Filter function turned off Filter function turned on CALCulatenINTegralSTATe Integrate function turned off Integrate function turned on Switches MATH2 function on CALCulatenMATHEXPRession Switches MATH1 function on CALCulatenMATHSTATe Query form CALCulatenTRANsformFREQuencyTYPE? Response ABS REL Selects relative MATH2-FFT calculation Switches MATH2-FFT onSelects MATH2-FFT-HANNing window CALCulatenTRANsformHISTogramSTATe SwitchesHistogram function turned off Histogram function turned on Syntax CALibrationALL Query form CALibrationALL? CALibrationALLResponse 0 Description Reads condition register Starts auto calibrationConditions Syntax CONFigureVOLTagemeasurefunction CONFigureSyntax elements are specified with the MEASure? query Channel 2 AC coupled Signal on channelExpected voltage 600 mV Initiates + fetches AC-RMS Response NR3 DISPlayBRIGhtnessQuery form DISPlayBRIGhtness? MINimum MAXimum NR30.00E00 .. .00E00 DISPlayMENUNAME DISPlayMENUSTATe Switches TB Mode menu display onDisplay turned off Display turned on Syntax DISPlayWINDow1TEXTnDATA? Type Analog Mode Digital ModeDISPlayWINDow1TEXTnDATA? Response is peak-peak value of 608.4 mV MEAS1 Display on DISPlayWINDow2TEXT1CLEar Clears all user text Sends 25 decimal DISPlayWINDow2TEXT1DATAAs text Character byte Command Reference DISPlayWINDow2TEXT1STATe FETChVOLTagemeasurefunction? 54COMMAND ReferenceFETCh? Voltageparameters, measureparameters Restrictions Acquisition FORMatDATA INT,8 HCOPyDATA? HCOPyDEVice INITiateCONTinuous Response 1 Trigger level becomes INITiateIMMediateSyntax INITiateIMMediate Single shot acquisition INPutnCOUPling Query form INPutnFILTerLPASsSTATe? INPutnFILTerLPASsSTATe INPutnFILTerLPASsFREQuency?Response 2.00E+07 Common low pass filter off Common low pass filter on INPutnIMPedance After a *RST command, the impedance is 1 MΩSyntax INPutnIMPedance NRf MINimum MAXimum 1E6 INPutnPOLarity Response Norm INV Description DIG INSTrumentNSELect INSTrumentSELectResponse DIG Anal Anal Channellist = MEASure?Measurefunction measureparameters Falltime High PDUTycycle Referencemiddle Signal. The peak to peak value is the difference betweenFirst falling edge equals the REFerence MIDDle until Ratio percentage of the positive width PWIDth Risetime Measureparameters Referencemiddle is volt Expectedperiod = NRf DEFault Executed. The unit of timeresolution is secondFrequencyresolution = NRf DEFault Periodresolution = NRf DEFault Limitations Description 74COMMAND Reference Syntax READVOLTagemeasurefunction? Example SENSeAVERageSTATe Response Scal SENSeAVERageCOUNt SENSeAVERageTYPE?Syntax SENSeAVERageCOUNt NRf 8 16 SENSeAVERageTYPE? Initiates trace averaging SENSeFUNCtionOFF SENSeFUNCtionON SENSeFUNCtionSTATe? Addition of channel i+j is off Addition of channel i+j is on Limitations SENSeSWEepOFFSetTIME SENSeSWEepPDETectionSTATe Slope = either pos. or neg Real-time mode switched off Real-time mode switched onSENSeSWEepREALtimeSTATe Reads AC-RMS Query form SENSeSWEepTIME? MINimum MAXimum MTB values in the digital modeSENSeSWEepTIME Base range is limited to 10 μs non-alternating time base Reads sweep time Coupled valuesRequests sweep time Requests nr of trace points Sets trigger source CH1 Autoranging MTB switched off Autoranging MTB switched onSENSeSWEepTIMEAUTO Sets autoranging MTB on SENSeVOLTagenDCRANGeAUTO Switches CH1 onSwitches CH2 on Autoranging CH2 SENSeVOLTagenDCRANGeOFFSet Channel SENSeVOLTagenDCRANGePTPeak Query form SENSeVOLTagenDCRANGePTPeak? MINimum MAXimum 100 mV/div Peak-to-peak =Sensitivity = 0.8 / 8 = Trigger source = Response NR1 Description BIT Decimal Meaning Number Value Following table defines the effect of STATusPRESet STATusPRESetSyntax STATusPRESet Status Register Filter / Enable Preset Value Response NR1 Description Enables report of TEMPerature too high/low 0 TEMPerature too high or too lowReturned value 16 equals bit 4 set temperature too high/low Enables report of TEMPerature within allowed limits 1 STATusQUEueNEXT? No errorError number is -222 and the meaning is Data out of range 350,Queue overflow Beeps on error Beeper disabled Beeper enabledReads the error queue SYSTemBEEPer SYSTemBEEPerSTATe Response on Stan Wire controlStan Even ODD None XONNone Response 7 1200 Response XON NoneNo X-on/X-off handshaking Becomes SYSTemDATE Sets the system date to Nov 7 SYSTemERRor? SYSTemKEY Response NR1 Front Panel KEY Enables Utility softkey menu Returns the last key simulation SYSTemSET Nodenr nodelength firstbyte ... lastbyte SYSTemTIME Syntax SYSTemVERSion? *RST command doesn’t change the current Scpi versionSYSTemVERSion? Response YYYY.V TRACeCOPY TRACeDATA Response definiteblock Initiates single acquisition Queries peak-to-peak Requests channel 1 traceReads channel 1 trace Reads peak-to-peak TRACePOINts Requests M23 trace Number of trace points for allReads M23 trace Sets high-pass filter on Pass BooleanSets high-pass filter off Low-pass filter active High-pass filter active HF-reject DC coupling HF-reject AC coupling KHz LF-reject Automatically switchesFilter Frequency LOW-PASS on HIGH-PASS on Low-Pass filter off TRIGgerSTARtFILTerLPASsFREQuency NRf TRIGgerSEQuence1FILTerLPASsFREQuency NRfTRIGgerSEQuence1FILTerLPASsSTATe Boolean TRIGgerSTARtFILTerLPASsSTATe Boolean Frequency LOW-PASS on HIGH-PASS on FilterSets cutoff frequency = 30 KHz TRIGgerSEQuence1HOLDoff TRIGgerSTARtHOLDoff TRIGgerSTARtLEVel NRf MINimum MAXimum TRIGgerSEQuence1LEVel NRf MINimum MAXimumTRIGgerSEQuence1LEVelAUTO Boolean TRIGgerSTARtLEVelAUTO Boolean Div. sensitivity Trigger source BecomesChannel Continuous initiation Trigger level becomes 0.2 POS After a *RST command, the trigger slope is POSitiveTRIGgerSEQuence1SLOPe TRIGgerSTARtSLOPe NEG Triggering is done at positive Configures AC-RMS CH2Sets real-time mode on Rising and negative falling IMM TRIGgerSEQuence1SOURce TRIGgerSTARtSOURceEXT Trigger source Configures AC-RMS CH1Input channel 1 becomes Single initiation Edge TRIGgerSEQuence1TYPE TRIGgerSTARtTYPESelects edge triggering Selects lines triggering Numb Selects video lines Linenr = linenr + 625/2 linenr = linenr 625/2Selects TV video Selects video line Secam Ntsc Hdtv Scam Secam Scam Lines/frame Selects Secam SelectsLines/frame Selects Lines/frame Selects Hdtv Positive video signal polarity selected Response POS NEG 123 Selects Negative Video Signal polarity PAL or Secam From 1 to Error reporting is invoked as follows Call errorcheck Making a Hardcopy of the Screen Pass/Fail TestingApplication Program Examples FETChNWIDth? Making automatic measurementsApplication summary Application program ’Termination Receive on EOI Making programmed measurements Acquiring Waveform Traces Reading measurement values Saving/Recalling Instrument Setups Save/recall settings to/from internal memory Application summary Application program CombiScope Instrument Making a Hardcopy of the ScreenIeee Pass/Fail Testing Saving a pass/fail test setup Application program Restoring a pass/fail test setup Running a pass/fail test DISPlayMENU MEASure Cross References Cross Reference Front Panel Keys / CommandsChannel 4 is external trigger input for PM33x0B Page Cross Reference Softkey Menus / Commands Acquire menu Programmable with the *SAV/*RCL and Systset commands Cursors menu Display menu Ext instead of ch4 for PM33x0B Mathplus Math menu Other functions with RCL/SAV and Systset Yes no Page Measure menu DTB DEL’D TB menu Setups menu SAVE/RECALL menu TB Mode menu Systset RCL/SAV Analog Mode Trigger menu Logic Wire Utility menu Ieee Vertical menu Inpfilt Onoff INP1IMP INP2IMP INP3IMP INP4IMP Cross Reference Functions / Commands BW Limit Function + KEYS/MENUS Related Scpi Commands AutosetAverage Calibration Autocal Delayed Timebase DEL’D TB DelayDelay Measurement Differentiate Mathplus Hold OFF FFT ON/OFFHistogram Mathplus CH1 Magnify Horizontal Integrate MathplusLogic Trigger Main Time Base Power Supply Function + KEYS/MENUS Related Scpi Commands MathematicsPass Fail Testing Mathplus SAV, *RCL Measure Menu Remote Control RS-232 Remote Control IEEE-488.2Remote Setup Probe Utilities Subtract Mathematics Function + KEYS/MENUS Related Scpi CommandsStatus Screen Text OFF Multi TrigSingle Roll Trigger Level Trigger CouplingTrigger DEL’D TB Trigger Main TB Util Menu User TextUtil Screen & Sound DISPlayWINDow1TEXT12DATA? Abbreviations Used IEC IDYIDN IFC RQC Manual Conventions RAMREN RQS List of Tables Glossary of Symbols Used4MANUAL Conventions List of Figures Documents Referenced Standards Information TRIGgerSEQuence1 STARtVIDeoFORMatTYPE type command PurposeScpi Conformance Information Or abbreviation, e.g., type = Hdtv List of Implemented IEEE-488.2 Syntactical Elements Program Data Separator Command Program HeaderStandards Information Program Message Unit Separator Program Header Separator Probe scale settings End node settingsChannel 1/2/3/4 settings Common vertical settings Cursor settings Delayed timebase settingsEvent trigger delay settings Cursor autosearch settings Trace intensity settings MATH1/2 settingsDisplay settings Display trace position settings Numerics Index Index Index Index Index Index Index Index Index Index Index Index