Keithley 2611A User Manual

A-8 Return to Section Topics 2600AS-900-01 Rev. B / September 2008
Appendix A: Frequently Asked Questions Series 2600A System SourceMeter
®
Instruments User’s Manual
Figure A-4
Connecting channels in parallel for higher current
How do I make contact check measurements?
Contact check connections
The contact check function prevents measurement errors due to excessive resistance in the force
or sense leads caused by poor contact at the DUT, failing relay contacts on a switching card, or
wires that are too long or thin. The contact check function will also detect an open circuit that may
occur with a four-point probe is misplaced or misaligned.
Figure A-5 shows Model 2601A/2602A/
2611A/2612A contact check connections, and Figure A-6 shows Model 2635A/2636A contact
check connections. R
C
is the resistance of the mechanical contact at the DUT, and R
S
is the series
resistance of relays and cables.
Figure A-5
Model 2601A/2602A/2611A/2612A contact check connections

Chan B
Chan A
2602A #1,
2612A #1,
or
2636A #1
+

+

Chan B
Chan A
2602A #2,
2612A #2,
or
2636A #2
+

+
DUT
I1 I2
I3
I4
IT = I1 + I2 + I3 +14
S LO
LO
CHANNEL A
LO GLO HI G G G HI
SS
KEITHLEY Model 2601A/2602A/2611A/2612A
HI
S HI
DUT
R
S
R
S
R
S
R
S
R
C
R
C
R
C
R
C
Cable/relay
resistance
Contact
resistance

Keithley 2611A Specifications

General

Brand	Keithley
Model	2611A
Category	Measuring Instruments
Language	English