XITRON 2000I, Руководство пользователя

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2000I & 2000M User Guide, Rev B
Internal Calibration
You may command an automatic internal calibration of internal zero offsets
whenever desired. Remotely command an internal calibration via either
interface by sending the command string “
I”. The progress of the internal
calibration can be obtained (for both interfaces) by reading the 2000
instrument display data as described in the
Maintenance and Calibration
chapter.
The accuracy specifications presented in the Appendix A tables assume the
use of this function at least every 30 days, or for a temperature change of
greater than 5ºC from that at the previous internal calibration.
External Calibration
You may command an external calibration whenever desired. Remotely
command an external calibration via either interface by sending the command
string “
X”. To prevent unauthorized access, an optional password protection
scheme is used.
A one-year external calibration interval is recommended for normal use.
Reduce this interval if greater accuracies are required. While calibration at
23ºC ambient is highly recommended, this may be performed at any
temperature from 10ºC to 35ºC without degradation of accuracy
specifications. The accuracy figures in the Appendix A tables are valid for
temperatures up to 5ºC from this temperature. When used in less accurate
applications, the external calibration interval may be extended up to three
years, the accuracies achieved are shown in the respective tables.