Arbiter Systems 931A, Operation Manual

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Appendix A
RS-232C Commands
A.1 Introduction
The following appendix contains a listing of commands, definitions and
examples that may be used to control and communicate with the Model
931A via the RS-232C serial interface.
Commands that request information from the instrument return either
current or previously logged data. Numeric data is returned as an ASCII
string of numeric characters, with leading sign and embedded decimal point
as needed. The string is terminated with carriage return and line feed
characters.
Take care to completely set up the desired measurement prior to
issuing a data request command. Verify that the following items are setup
properly:
Channel 1 and 2 Input Signal: Use Channel 1 if only one signal is
to be measured. Set Channel 1 to measure AC voltage and Channel 2 to
measure AC current, if measuring power quantities (power, VARS, VA, or
power factor).
Measurement Bandwidth: To measure fundamental frequencies only,
select the narrow-band mode. Select the wide-band mode for measure-
ments to include all harmonics up to 3.05 kHz.
Minimum and Maximum: Set the display for each parameter for the
desired minimum, maximum, average or present values. Before requesting
data, set the display using the MMN command.
Note 1: Use the EEP command to permanently store Calibration Data
in the EEPROM.
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