Keithley 617 User Manual

!
I= ROS BY 617
-I
lSTAT”S BYTE ONLY)
I= ERROR
IA
I
1 =REAOING
OVERFLOW
1 = DATA STORE
1= READY I= READING DONE
Figure 3-10. SRQ Mask and Status Byte Format
Bit 6 provides a means for you to determine if SRQ was
asserted by the Model 617. If this bit is set, service was re-
quested by the instrument. Bit 5 flags a Model 617 error con-
dition, which can be further checked with the Ul corn-
mand. If this bit is set, one of the following errors has
occurred:
1. An illegal device dependent command (IDDC) or illegal
device dependent command option (IDDCO) was trans-
mitted.
2. The instrument was programmed when not in remote.
3. A trigger overrun has occurred (the instrument was trig-
gered while processing a reading from a previous trigger).
4. A number error has occurred (calibration or voltage source
values were out of limits).
Keep in mind that you can program the instrument to assert
SRQ under any of these conditions simply by setting bit 5 in
the SRQ mask (M32X). Paragraph 3.10.18 describes how to
use the Ul command to obtain information on the type of
error from the instrument. The LJl command is used to clear
the error bit and restore operation of SRQ on error after the
error byte is read.
The bits in the status (serial poll) byte have the following
meanings:
Reading Overflow (Bit O&Set when an overrange input is
applied to the instrument (except when a current overload oc-
curs in V/I ohms). Cleared when a non-overflowed reading is
available.
Data Store Full (Bit 1)-&t when all 1OO readings in data
store have been taken. Cleared by reading a stored reading
over the bus (B1X).
Reading Done (Bit 3)--S& when the Model 6l7 has com-
pleted the present reading conversion. Cleared by re-
questing a reading over the bus.
Ready (Bit4)-Set when. the instrument has processed all
previously received commands and is ready to accept addi-
tional commands over the bus.
Error (Bit 5)-Set when an error condition occurs, as describ-
ed above. Cleared by reading the error word with the U1
command.
RQS (Bit 6)--S& if the Model 617 has asserted SRQ.
Bits 2 and 7 are not used, and are always set to 0.
Note that the status bite should be read to clear the SRQ line
once the instrument has generated an SRQ. All bits in the
status byte will be latched when the SRQ is generated. Bit 6
(RQS) will be cleared when the status byte is read.
Even with SRQ disabled, the status byte can be read to deter-
mine appropriate instrument conditions. In this case, bits 0,
1, 3, and 4 will be continuously updated to reflect current in-
strument status; however, bit 5 (the error bit) will latch and
remain so until the U1 status word (paragraph 3.10.18) is
read, even if no SRQ occurs.
HP-85 Programming Example-Enter the following pro-
gram into the HP-85:
PROGRAM
COMMENTS
10 REMOTE 717 @ CLEAR 7
20 OUTPUT 727;“M32X”
30 OUTPUT 727;“KSX”
set up for remote
operation, clear
instrument.
Program for SRQ on
error.
Attempt to program
40 S = SPOLL(727)
illegal option.
Serial poll the instru-
ment.
50 DISP”B7 B6 85 84 83 B2 Bl
Identify the bits.
RW’
60 %R 1=7TO 0 STEP -1
70 DISP BIT (S.1):
80 NEXT I
90 DISP
100 END
Loop eight times.
Display each bit posi-
tion.
Once the program is entered and checked for errors, press the
HP-85 RUN key. The computer first places the instrument in
remote (line 10) and then programs the SRQ mode of the in-
strument (line 20). Line 30 then attempts to program an illegal
command option, at which point the instrument generates an
SRQ and sets the bus error bit in its status byte. The com-
puter then serial polls the instrument (line 40). and then
displays the status byte bits in proper order on the CRT. In
this example, the SRQ (B6) and error (B5) bits are set because
of the attempt to program an illegal command option (KS).
Other bits may also be set depending on instrument status.
3-29

Keithley 617 Specifications

General

Brand	Keithley
Model	617
Category	Measuring Instruments
Language	English

Summary

Warranty Information

Warranty

Details the warranty terms and conditions for the product and specific components.

Specifications

Specifications

Details the electrical and performance specifications for the Model 617 electrometer.

Safety Precautions

Safety Precautions

Advises on essential safety measures to avoid injury and instrument damage during operation.

Section 1: General Information (Continued)

Unpacking and Getting Started

Details unpacking, inspection, and initial steps to operate the Model 617.

Section 2: Operation

2.2 Power Up Procedure

Details the steps for connecting power and turning on the instrument.

2.3 Power Up Self Test and Display Messages

Explains the self-test routine and potential display messages upon startup.

Section 2: Operation (Continued)

2.4 Front Panel Familiarization

Provides an overview of the Model 617's front panel layout, controls, and indicators.

2.7 Basic Measurement Techniques

Introduces fundamental procedures for making voltage, resistance, charge, and current measurements.

2.7.2 Input Connections

Details how to connect input signals to the rear panel INPUT connector.

2.7.4 Guarded Operation

Explains the concept and application of guarding to minimize leakage and improve measurements.

2.7.5 Making Current Measurements

Details the procedure for measuring low-level currents, including picoampere ranges.

2.7.6 Making Charge Measurements

Describes how to measure charge using the Model 617's coulombs ranges.

2.7.7 Resistance Measurements

Explains how to measure resistance using constant current and voltage methods.

2.8 Using The Voltage Source

Explains how to use the Model 617's built-in voltage source for V/I measurements.

2.10 Using External Feedback

Explains how to extend capabilities using external feedback networks.

2.11 Using Zero Correct and Baseline Suppression

Covers instrument offset cancellation and baseline value storage.

2.11.2 Using Suppression

Details how to store an offset value and subtract it from subsequent readings.

2.13 External Triggering

Explains how to trigger the instrument using external BNC connectors.

2.4.1 Controls

Describes the function and operation of each front panel control button.

2.5.3 Calibration

Introduces the digital calibration program for front panel or IEEE-488 bus use.

2.7.3 Making Voltage Measurements

Provides step-by-step instructions for measuring DC voltages with the Model 617.

2.8.1 Basic Operating Procedure

Guides on connecting and adjusting the voltage source output.

2.11.1 Zero Correct and Zero Check

Explains how to use Zero Correct and Zero Check to cancel internal offsets.

2.12 Data Storage

Describes the internal 100-point data store mode for logging readings.

2.13.1 External Trigger

Details continuous and one-shot triggering modes via the external trigger input.

2.14 Measurement Considerations

Discusses factors affecting measurements at low signal levels.

2.8.2 V/I Resistance Measurements

Describes how to measure high resistances using the voltage source and electrometer.

Section 3: IEEE-488 Programming

Section 3: IEEE-488 Programming (Continued)

3.4 Bus Commands

Covers device commands, grouped into uniline, multiline, and device-dependent categories.

3.7.2 Bus Connections

Details how to connect the Model 617 to the IEEE-488 bus using appropriate cables.

3.7.3 Primary Address Programming

Explains how to check and set the instrument's primary address for bus communication.

3.8 Software Considerations

Discusses software aspects for IEEE-488 controllers like HP-85 and IBM-PC.

3.9 General Bus Command Programming

Covers general bus commands like DCL, REN, IFC, LLO, GTL, SDC, GET, SPE, SPD.

3.10 Device-Dependent Command Programming

Details commands controlling modes like function, range, trigger, and data format.

3.10.2 Function (F)

Describes commands to select measurement functions like Volts, Amps, Ohms, Coulombs.

3.10.3 Range (R)

Explains commands for controlling instrument sensitivity and selecting measurement ranges.

3.10.4 Zero Correct and Zero Check (Z and C)

Details commands for canceling internal offsets and zeroing the instrument.

3.10.5 Baseline Suppression (N)

Explains commands to store an offset and subtract it from subsequent readings.

3.10.9 Voltage Source Value (V)

Details commands for programming the built-in voltage source output.

3.10.10 Voltage Source Operate (O)

3.10.12 Non-Volatile Memory Storage (L)

3.10.14 Trigger Mode (T)

3.10.15 SRQ Mask (M) and Status Byte Format

3.11.2 Number Error

3.4.5 Device-Dependent Commands

Describes commands specific to device configuration, controlling functions like mode and range.

3.10.8 Data Store Mode

Explains how to use the data store for logging readings and setting intervals.

3.10.11 Calibration Value (A)

Describes commands for setting calibration values for ranges and functions.

3.10.18 Status (U)

3.11.1 Bus Error

Section 4: Applications

4.2 Insulation Resistance Measurements

Details how to measure high insulation resistances using constant current and voltage methods.

Section 4: Applications (Continued)

4.3 High Impedance Voltmeter

Explains using the Model 617 as a high-impedance voltmeter with minimal circuit loading.

4.5 Diode Characterization

4.6 Capacitor Leakage Measurements

4.4 Low-Level Leakage Current Measurements

Guides on measuring low-level currents like nanoamperes and picoamperes.

4.7 Capacitance Measurement

4.10 Using The Model 617 With External Voltage Sources

Section 5: Performance Verification

Section 5: Performance Verification (Continued)

5.5 Verification Procedures

Provides detailed procedures for verifying accuracy of volts, ohms, amps, and coulombs functions.

5.5.3 Coulombs Verification

5.5.4 Volts Verification

5.5.5 Ohms Verification (2kΩ–20MΩ Ranges)

5.5.7 Voltage Source Verification

5.5.1 Input Current Verification

5.5.6 Ohms Verification (200MΩ and GΩ Ranges)

5.5.2 Amps Verification

Section 7: Maintenance

7.2 Line Voltage Selection

Section 7: Maintenance (Continued)

7.3 Fuse Replacement

7.4.5 Front Panel Calibration

Provides step-by-step instructions for calibrating from the front panel.

7.4.7 Calibration Sequence

7.4.11 Amps Calibration

Provides calibration steps for the amps function across various ranges.

7.4.12 Coulombs Calibration

Details the procedure for calibrating the coulombs function.

7.4.14 Ohms Calibration

Provides calibration steps for the ohms function across various ranges.

7.4.15 Voltage Source Calibration

Details the procedure for calibrating the instrument's internal voltage source.

7.6 Disassembly Instructions

7.7.2 Power Up Self Test

7.7.7 A/D Converter and Display

7.7.8 Input and Ranging Amplifiers

7.4 Calibration

Introduces digital calibration capabilities and recommendations.

7.4.6 IEEE-488 Bus Calibration

Details procedures for calibrating the instrument via the IEEE-488 bus using a computer.

7.4.8 Input Offset Adjustment

Describes steps to null any small offset in the input amplifier.

7.4.13 Volts Calibration

Outlines the calibration steps for the volts function across different ranges.

7.7 Troubleshooting

Offers guidance for diagnosing and resolving instrument problems.

7.7.3 Self Diagnostic Program

7.4.9 Input Current Adjustment

Details procedures to null input current in the input stage for temperature compensation.

7.4.10 Permanent Storage of Calibration Parameters