L (Calibration; Low Temperature Point) - Keithley 263 Instruction Manual

IEEE-488 PROGRAMMING
4.7.6
L (Calibration; Low Temperature Point)
Purpose
Use to send calibration values to calibrate the low ("cold") temperature point for
the lG& lOG0 and 1OOGn resistors.
Format
Ln
Parameters
Ln.nnnnEnn Calibration value using exponent.
Description In general, each of the three gigaohm resistors are calibrated at two temperature
points so that temperature coefficient (TC) profiles can be established. Because the
instrument constantly measures its internal temperature and knows the actual TC
of each gigaohm resistor, it can calculate the actual resistance of the resistor at any
temperature. This is the temperature compensation feature of the instrument. The
L command is used to send the calibration value for each of the three gigaohm
resistors at the low ("cold") temperature point. The A calibration command is used
to calibrate the high ("hot") temperature point of the gigohm resistors (see paragraph
4.72).
Programming
1. Only as many significant digits as necessary need be sent. Example:
Notes
Send Ll.OlE9X instead of Ll.OllNE09X
2. The instrument will ignore the digits of any calibration value that exceeds 5%
digits. For example, if a calibration command value of 1.882067 is sent, the seven
will be ignored and 1.88206 will be displayed.
Programming
Example
CAUTION: The following example is only intended to show proper syntax. Only
send calibration commands when actually calibrating the instrument. The inadver-
tent sending of the L command may adversely affect calibration of the Model 263.
A complete IEEE-488 calibration program is contained in Section 8 (Maintenance)
of this manual.
,:,,JTp,jT 78:3 ,: 6 6 F<,F:4L1 :3:32'r3F,E'3>.:! ?
! Calibrate low temperature point of 1Gfl
resistor using the "ladder".
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