KEPCO KLP Series (older -1200 models) Operator Manual - Manual (Page 60)

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KLP073008
3.6.1 SCPI MESSAGES
There are two kinds of SCPI messages: program messages from controller to power supply,
and response messages from the power supply to the controller. Program messages consist of
one or more properly formatted commands/queries and instruct the power supply to perform an
action; the controller may send a program message at any time. Response messages consist of
formatted data; the data can contain information regarding operating parameters, power supply
state, status, or error conditions.
3.6.2 COMMON COMMANDS/QUERIES
Common commands and queries are defined by the IEEE 488.2 standard to perform overall
power supply functions (such as identification, status, or synchronization) unrelated to specific
power supply operation (such as setting voltage/current). Common commands and queries are
preceded by an asterisk (*) and are defined and explained in Appendix A. Refer also to syntax
considerations (PARs 3.4.3 through 3.4.6).
3.6.3 SCPI SUBSYSTEM COMMAND/QUERY STRUCTURE
Subsystem commands/queries are related to specific power supply functions (such as setting
output voltage, current limit, etc.) Figure 3-3 is a tree diagram illustrating the structure of SCPI
subsystem commands used in the KLP Power Supply with the “root” at the left side, and specific
commands forming the branches. The following paragraphs introduce the subsystems; sub-
system commands are defined and explained in Appendix B.
3.6.3.1 ABORT SUBSYSTEM
This subsystem allows pending trigger levels to be cancelled.
3.6.3.2 DISPLAY SUBSYSTEM
This subsystem returns the character string displayed in the Status display.
3.6.3.3 TRIGGER SUBSYSTEM
This subsystem enables the trigger system. When an internal trigger is enabled, the triggering
action will occur upon receipt of a GPIB , *TRG or TRIGger command. When an external
trigger is enabled, the triggering action occurs when a ground is applied to J2, pin 14. If a trigger
circuit is not enabled, all trigger commands are ignored.
3.6.3.4 LIST SUBSYSTEM
The LIST subsystem is represented by the 100 memory locations (groups of settings) which are
stored in the volatile memory. Each setting contains values for: Current, Voltage, Dwell, and
Relay. The range for the first two values is the maximum available range for the specific power
supply. The range for the dwell time is between 0.01 and 655.36 seconds. If the relay is config-
ured to LIST (see PAR. 3.2.11.3), it can be set to 1 (on, energized) or 0 (off, de-energized).
3.6.3.5 MEASURE SUBSYSTEM
This query subsystem returns the voltage and current measured at the power supply's output
terminals.