Agilent Technologies N3280A manual Overvoltage Protection, Output Current, Output Mode

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5 - Programming the DC Source

Overvoltage Protection

The dc source will turn off its output and open the output relays if the output voltage exceeds +11.5V ( ±0.3V) or −11.5V ( ±0.3V) when measured at the output terminals. Overvoltage protection is only available when operating in voltage priority mode. It is enabled with:

VOLT:PROT:STAT<bool>,(@<channel list>) where <bool> is the protection state (0 OFF; 1 ON).

CAUTION: If overvoltage protection is disabled, the dc source or the equipment under test will not be protected from excessive external voltages.

Output Current

When operating in voltage priority mode, the dc source has a programmable current limit, which applies to both positive and negative output currents. The command to program the current limit is:

CURR:LIM <n>,(@<channel list>) where <n> is the current limit in amperes.

If the load attempts to draw more current than the programmed limit, the output voltage is reduced to keep the current within the limit.

To query the maximum output current limit that can be programmed, use:

CURR:LIM? MAX,(@<channel list>)

When operating in current priority mode, the dc source has a programmable output current. The maximum output current that can be programmed in current priority mode is ±0.5125 mA. The command to program the current is:

CURR <n>,(@<channel list>)

To query the programmed output current setting for output 1, use:

CURR?,(@<channel list>)

Output Mode

You can program the unit to operate in either voltage priority or current priority mode. In voltage priority mode the output is controlled by a constant voltage feedback loop, which maintains the output voltage at its programmed setting. In current priority mode the output is controlled by the constant current feedback loop, which maintains the output load or source current at its programmed setting.

Use the following command to configure the output mode:

FUNC:MODE <mode>,(@<channel list>)

where <mode> is the operating mode (VOLT CURR)

NOTE: If the output is on, changing the output mode will cause the output to turn OFF, cycle modes, and then turn ON. Also, there is no interaction or coupling between modes. Switching back and forth between modes does not change the programmed values.

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Contents USER’S Guide Agilent Technologies Model N3280A Component Test DC SourceWarranty Information CertificationSafety Summary GeneralSafety Symbols Declaration Acoustic Noise Information Printing HistoryTable of Contents Types of Scpi Commands Scpi Command Completion Using Device ClearExternal References Gpib Capabilities of the DC Source Introduction to ScpiScpi Programming Commands At a Glance Calibration Commands Measurement CommandsOutput Commands Status CommandsSystem Commands Trigger CommandsCommon Commands Voltage Priority TestsRipple and Noise Tests Error Number List 103Transient Response Tests Page Safety Considerations Document OrientationOptions and Accessories DescriptionRemote Programming Option DescriptionOutput Characteristics Voltage Priority OperationOutput Characteristic Current Priority Current Priority OperationMeasurement Characteristics Start of a Measurement Cleaning InspectionDamage Packaging Material Additional ItemsLocation Bench OperationRack Mounting Do not block the fan exhaust at the rear of the unitPower Connections Connect the Power CordOutput Connections Turn the unit off before connecting any wiresOutputs 1 Current Ratings Voltage Drops and Lead ResistanceAmpacity and Resistance of Stranded Copper Conductors AWG No Maximum Ampacity Resistance at 20 deg. C Free airCoaxial Guard Connections Guard Connections for Test FixturesExternal Trigger Connections Computer ConnectionsMaintaining Stability OVP ConsiderationsSettings for Power Module Configuration Switch Switch SettingSwitch Setting Address Gpib AddressFront Panel Description Procedure Checkout ProcedureExplanation Selftest Error Messages Runtime Error MessagesPower-On Selftest Errors Case of TroublePage External References Gpib Capabilities of the DC SourceGpib References Scpi ReferencesIntroduction to Scpi Types of Scpi CommandsConventions Used in This Guide Multiple Commands in a Message Including Common CommandsUsing Queries Moving Among SubsystemsMessage Unit Types of Scpi MessagesChannel List Parameter Scpi Data Formats Scpi Command Completion Suffixes and MultipliersResponse Data Types Class Suffix Unit Unit with MultiplierUsing Device Clear Outputstate ExamplePage Power-on Initialization IntroductionProgramming the Output Enabling the OutputOvervoltage Protection Output ModeOutput Current Oscillation Protection Triggering Output ChangesOutput Trigger Model Enabling the Output Trigger System Setting the Voltage and Current Trigger LevelsSelecting the Output Trigger Source Generating Output Triggers Making MeasurementsAverage Measurements Power Line Cycles Measurement Samples and Time IntervalTriggered Measurements Current RangesWindow Functions Returning All Measurement Data From the Data BufferEnabling the Measurement Trigger System Measurement Trigger ModelSelecting the Measurement Trigger Source Selecting the Sensing Function Output Settling DelayGenerating Measurement Triggers Pre-trigger and Post-trigger Data Acquisition Pre-trigger and Post-trigger AcquisitionProgramming the Status Registers DC Source Status ModelBit Configurations of Status Registers Operation Status GroupQuestionable Status Group Standard Event Status GroupStatus Byte Register MSS and RQS BitsDetermining the Cause of a Service Interrupt Servicing Operation Status and Questionable Status EventsCommon Commands Subsystem CommandsProgramming Parameters Subsystem Commands Syntax Scpi Programming Commands At a GlanceSave new cal constants in non-volatile memory Mode mode, @list DELay FUNCtion Mode mode, @list VOLTageSets the output voltage in voltage priority mode Sets the triggered output voltage in voltage priority modeCommon Commands Syntax ESE nSRE n Output Programming ParametersCalibration Commands CALibrateCURRentCALibrateCURRentLIMitPOSitive CALibrateCURRentLIMitNEGative CALibrateCURRentMEASureCALibratePASSword CALibrateDATACALibrateDATE CALibrateLEVelCALibrateSTATe CALibrateSAVECALibrateVOLTage Measurement Commands FETChARRayCURRent? FETChARRayVOLTage?FETChCURRent? FETChVOLTage? Query SyntaxMEASureARRayCURRent? MEASureARRayVOLTage? MEASureCURRent? MEASureVOLTage?SENSeCURRentRANGe Enter values greater than 0.015ASENSeFUNCtion SENSeSWEepNPLCyclesSENSeSWEepOFFSetPOINts Query Syntax SENSeFUNCtion? @channel listSENSeSWEepTINTerval SENSeSWEepPOINtsSENSeWINDow Output Commands OUTPutOUTPutOSCProtect OUTPutPROTectionCLEarDefault Suffix SOURceCURRentIMMediate SOURceCURRentTRIGgeredSOURceCURRentLIMitIMMediate SOURceCURRentLIMitTRIGgered SOURceCURRentLIMitBWIDthSOURceDELayMODE SOURceDELaySOURceCURRentMODE SOURceCURRentLIMitMODE SOURceFUNCtionMODE SOURceVOLTageALCBWIDthSOURceVOLTageIMMediate SOURceVOLTageTRIGgered Query Syntax SOURceFUNCMODE? @channel listSOURceVOLTageMODE SOURceVOLTagePROTectionSTATeQuery Syntax SOURceVOLTagePROTectionSTATe? @channel list NR10 orStatus Commands STATusOPERationENABleBit Configuration of Operation Status Registers STATusOPERationEVENt?STATusPRESet Parameters Preset ValueCommand Syntax STATusPRESet Parameters None Examples STATusOPERationNTR STATusOPERationPTRSTATusQUEStionableENABle Query Syntax STATusQUEStionableENABle? @channel listSTATusQUEStionableCONDition? STATusQUEStionableNTR STATusQUEStionablePTRSYSTemERRor? System CommandsSYSTemVERSion? Trigger Commands ABORtINITiateNAME TRIGgerACQuireTRIGgerACQuireSOURce TRIGgerTRANsientSOURceTRIGgerTRANsient RST ValueCommon Commands Command Syntax *CLS Parameters NoneParameters Power-On Value Examples Bit Configuration of Standard Event Status Enable RegisterExample Field InformationQuery Syntax *OPT? Returned Parameters Aard Power-on Value RST SettingsBit Configuration of Status Byte Register Query Syntax TST? Returned Parameters NR1Table A-1. Specifications Table A-2 Supplemental Characteristics Output Common Mode SafetyDimensions WeightFigure A-1. Output Impedance Graphs all outputs Equipment Required Performance & Verification Tests Measurement TechniquesElectronic Load Test SetupProgramming Program Commands Voltage Priority TestsVoltage Programming and Readback Accuracy Positive Current Limit +CLAction Program Commands Negative Current Limit -CLCurrent Priority Tests Current Programming and Readback AccuracyLoad Effect Tests Voltage Priority, Constant Voltage Load EffectVoltage Priority, +Current Limit Load Effect Voltage Priority, -Current Limit Load Effect TestCurrent Priority Constant Current Test Source Effect TestsVoltage Priority, Constant Voltage Source Effect Voltage Priority, +Current Limit Source Effect Voltage Priority, -Current Limit Source EffectCurrent Priority, Constant Current Source Effect Ripple and Noise Tests Voltage Priority Ripple and NoiseTransient Response Tests Voltage Priority, Transient Recovery TimeCurrent Priority Ripple and Noise Current Priority Transient Recovery Time Figure B-2. Transient Waveform Voltage PriorityPerformance Test Equipment Form Figure B-3. Transient Waveform Current PriorityPerformance Test Record Form Performing the Calibration Procedure Enable Calibration ModeNegative Current Limit Calibration Positive Current Limit Calibration5A Range Current Measurement Calibration 100Saving the Calibration Constants 15mA Range Current Measurement Calibration101 Changing the Calibration Password Calibration Error MessagesTable B-3. Gpib Calibration Error Messages Error MeaningTable C-1. Error Numbers Error Number List103 Error Messages 104Error Messages C 105Page Line Voltage Selection 107Page Earlier Version Output Connectors Mating Connector Part NumbersRear Panel Pinout Assignments CHG-2010-J01010-KEPPage Index 111Index 112113 Scpi114 United States Latin America Canada Australia/New ZealandEurope Asia Pacific JapanManual Updates