Keithley SourceMeter 3A 2420, Service Manual

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B-8 Command Reference
:DATA?
(:CALibration:PROTected:SENSe:DATA?)
(:CALibration:PROTected:SOURce:DATA?)
Purpose
To request the calibration constants for the active range.
Format
:cal:prot:sens:data?
:cal:prot:sour:data?
Response
Four comma-separated ASCII floating-point constants
Description
The :CAL:PROT:SENS:DATA? and :CAL:PROT:SOUR:DATA? queries re-
quest the calibration constants for the active range of the sense and source
functions respectively. The four returned constants are in ASCII floating-
point format delimited by commas.
Note
To request the appropriate constants, (1) select the source or sense function,
(2) choose the desired range, and (3) send the desired :DATA? query.
Example
:SENS:FUNC 'VOLT:DC'
Select DC sense function.
:SENS:VOLT:DC:RANGE 0.2
Choose 200mV range.
:CAL:PROT:SENS:DATA?
Request cal constants.
Detecting calibration errors
If an error occurs during any calibration step, the Model 2420 will generate an appropriate
error message. Several methods to detect calibration errors are discussed below.
Reading the error queue
As with other Model 2420 errors, any calibration errors will be reported in the error queue.
(You can read the error queue by using the :SYST:ERR? query.)
Error summary
Table B-4 summarizes calibration errors. These errors will occur under the following condi-
tions.
Error 500/501 — These errors will occur if you do not set the calibration date or calibration due
date.
Error 502
— This error will occur when the :CAL:PROT:SENS or :CAL:PROT:SOUR com-
mand is sent with a parameter that cannot be placed into any of the defined numeric ranges.
Error 503/504 — Will occur when the source/compliance DAC calibration constants generate
an invalid DAC setting. All of the source/compliance DAC calibration constants are verified
each time a :CAL:PROT:SOUR command is processed and when the Model 2420 is first turned
on. This error generally occurs when the Model 2420 source circuitry is defective.