In this section:
Verification and adjustment procedures ................................... 1-1
Verification interval ................................................................... 1-1
Recommended adjustment ...................................................... 1-1
Recommended test equipment ................................................ 1-2
Optimal test conditions ............................................................. 1-2
Verification tests ....................................................................... 1-3
Amplitude and flatness verification procedures ........................ 1-3
AC amplitude verification for high impedance .......................... 1-6
Verification and adjustment security ....................................... 1-13
Verification procedure and verification item adjustment tests. 1-14
Equipment setup .................................................................... 1-15
Verification and adjustment procedures
This manual contains procedures for verification and adjustment of the Keithley Instruments 3390.
The instrument features closed-case electronic calibration. Internal mechanical adjustments are not
required. The instrument calculates correction factors based upon the input reference value you set.
The new correction factors are stored in nonvolatile memory until the next adjustment is performed.
Nonvolatile FLASH calibration memory does not change when power has been off or after a remote
interface reset.
Verification interval
The instrument should be verified and adjusted on a regular interval determined by the measurement
accuracy requirements of your application. For most applications, verification and adjustment is
adequate for a 1-year interval. Only if the instrument is adjusted at regular verification and adjustment
intervals are the accuracy specifications warranted.
Recommended adjustment
Whatever verification interval you select, Keithley Instruments recommends that complete
readjustment should always be performed at the verification interval. This will assure that the Keithley
Instruments 3390 will remain within specification for the next verification interval. This criterion for
readjustment best provides long-term stability. Performance data measured, using this method, can
be used to extend future calibration intervals.
Section 1
Verification procedures