Keithley 6430 User Manual

Digital I/O Port, Interlock, and Output Configuration 12-9
GUARD
With this output-off state, the current source is selected and set to 0A. Voltage compliance is
set to 0.5% full scale of the present voltage range. This output-off state should be used when
performing 6-wire guarded ohms measurements or for any other load that uses an active
source.
NOTE When changing the output-off state with the output off, the selected output-off state
will be entered immediately.
Output off states and inductive loads
The output off state you select for inductive loads depends on how much energy the inductor
holds. The Normal output off state is not recommended as it lowers the compliance setting. The
Zero or the Guard state are better suited, as Zero does not change the compliance setting and
the Guard output off state would change the voltage source to a current source with a voltage
compliance. The Guard state is typically used only for guarded ohms measurements.
To protect the unit from inductive energy, the application may require a spark gap across the
INPUT HI and LO terminals. The SourceMeter does not have internal spark gap protection, as
some leakage current (nA) is associated with the protection circuits.
Remote output configuration
Output configuration commands
Table 12-2 summarizes output configuration commands. These commands include those to
enable and disable the interlock as well as commands to control output off states. See Section
17, OUTPut subsystem and SOURce subsystem for more information.
Table 12-2
Output configuration commands
Command Description
:OUTPut:INTerlock:STATe <state>
:OUTPut:INTerlock:TRIPped?
:OUTPut:SMODe <name>
:SOURce:CLEar
:SOURce:CLEar:AUTO <state>
:SOURce:CLEar:AUTO:MODE <name>
Enable/disable interlock (state = ON or OFF).
Query interlock tripped state (1 = tripped).
Select output-off mode (state = NORMal, ZERO, or GUARd).
Turn output source off when in idle state.
Enable/disable auto output-off. State = ON (output off after
measurement) or ON (output stays on).
Auto clear mode. Name = ALWays (every reading; default) or
TCOunt (ON when trigger layer entered; OFF when leaving
trigger layer).

Keithley 6430 Specifications

General

Type	Sub-Femtoamp Remote SourceMeter
Compliance Voltage	200 V
Maximum Output Voltage	200 V
Maximum Output Current	100 mA
Compliance Limit	Programmable
Interface	GPIB, RS-232
Input Impedance	>10^14 Ω

Summary

Safety Precautions

3 Basic Source-Measure Operation

Basic Source-Measure Procedure

Details setup for source-measure operations: function, values, limits, and output control.

5 Source-Measure Concepts

Compliance limit

Discusses compliance limits, values, and determination.

Operating boundaries

Covers voltage/current boundaries for source, sink, I-source, V-source, and source-measure modes.

6 Range, Digits, Speed, and Filters

Range and digits

Discusses available ranges, limits, manual/autoranging, and display resolution.

Speed

Filters

Provides information on 3-stage filtering to reduce reading noise.

7 Relative and Math

Math Operations

Details math (FCTN) operations: power, offset ohms, varistor, etc.

9 Sweep Operation

Configuring and Running a Sweep

Discusses setup, configuration, delay setting, and performing sweeps.

10 Triggering

Trigger Model

Discusses trigger model, layers, event detection, delay, and device action.

Configuring Triggering

Details how to configure various triggering aspects.

Remote Triggering

Details remote trigger model, commands, and basic triggering example.

11 Limit Testing

Types of Limits

Discusses three limit types: compliance, coarse, fine; summarizes grading and sorting modes.

Configuring and Performing Limit Tests

Describes configuration for limit tests and typical test procedure.

Remote Limit Testing

12 Digital I/O Port, Interlock, and Output Configuration

Digital I/O Port

Safety Interlock

Describes using Digital I/O Port as a safety interlock.

Front Panel Output Configuration

14 Status Structure

Programming and Reading Registers

Status Byte and Service Request (SRQ)

Explains programming Status Byte for SRQs and using serial poll to detect SRQs.

15 Common Commands

Command Summary

Lists IEEE-488.2 common commands used by the SourceMeter.

Command Reference

Provides detailed reference for common commands, excluding status structure.

16 SCPI Signal-Oriented Measurement Commands

Command Summary

Configuring Measurement Function

Provides detailed info on commands to configure measurement function.

Acquiring Readings

Describes commands to acquire post-processed readings, trigger, acquire, and single measurement.

17 SCPI Command Reference

18 Performance Verification

Verification Test Requirements

Recommended Test Equipment

Performing the Verification Test Procedures

Details restoring factory defaults, setting ranges, and output values.

Mainframe Verification

Covers procedures to verify mainframe accuracy alone.

19 Calibration

Recommended Calibration Equipment

Unlocking Calibration

Mainframe Calibration

Includes procedures to calibrate the mainframe without the Remote PreAmp.

20 Routine Maintenance

Line Fuse Replacement

Covers procedure and part numbers for replacing the line fuse.

Front Panel Tests

F Measurement Considerations

Floating measurement safety concerns

Discusses safety concerns for measurements up to 42V above chassis ground.

Low current measurements

Leakage currents and guarding

Explains reducing leakage currents using insulators, humidity control, and guarding.