Keithley 2182, Quick Reference Manual, Page: 25 / 30

Quick Reference Guide 19
Basic Delta calculation:
where: V1t1 is the voltage measurement on the positive phase of the current source.
V1t2 is the voltage measurement on the negative phase of the current source.
Delta Calculation using Filter and Rel:
where:
• FiltV1t1 and Filt V1t2 are filtered voltage measurements on the positive and nega-
tive phases of the current source. The “FILT” annunciator will be on when Filter is
enabled.
• RelV1 is the Rel value established for DCV1. The “REL” annunciator will be
on when Rel is enabled.
Delta is selected by pressing the SHIFT key and then the V1-V2 key. The “(Vt1-Vt2) / 2”
message appears briefly before displaying the result of the calculation. Delta is disabled by
selecting a single measurement function (DCV1, DCV2, TEMP1, or TEMP2) or by
selecting Ratio.
NOTE Delta measurements by the Model 2182 require the use of an alternating polarity
source. The source must have external triggering capabilities that are compatible
with the external triggering capabilities of the Model 2182. See Section 5 of the
Model 2182 User’s Manual for details.
Remote ratio and delta programming
SCPI commands
Table 11 summarizes commands used for ratio and delta.
Table 11
Ratio and delta SCPI commands
Command Description
:SENSe:FUNCtion ‘VOLtage’ Select voltage function.
:SENSe:CHANnel <chan> Select range control channel: 1 or 2.
:SENSe:VOLTage[:DC]:RATio <b> Enable or disable Ratio (V1/V2).
:SENSe:VOLTage[:DC]:DELTa <b> Enable or disable Delta. Not valid with
TEMP1 or TEMP2 selected.
:SYSTem:FAZero[:STATe] <b> Enable or disable Front Autozero. To double
the speed of Delta, disable Front Autozero.
Delta
V1t1 V1t2 –
2
-------------------------------- =
Delta
FiltV1t1 FiltV1t2
–
2
--------------------------------------------------- RelV1 – =