KEPCO BOP-MG 1KW, Руководство оператора

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BOP HIPWR 111315
Refer to Table 2-11 for input/output signal allocations for communication via the GPIB, Table 2-5
for RS 232, and Table 2-2 for the BITBUS. All power supply functions available from the keypad
can be programmed via remote SCPI commands. In addition, some features that are not avail-
able from the keypad may be implemented using remote commands (see PAR. 3.5.1).
This section includes a discussion of GPIB bus protocols (PAR. 3.5), instructions for changing
the GPIB address (PAR. 3.5.3.1.1), a discussion of the VISA (Virtual Instrumentation Software
Architecture) driver supplied with the unit (PAR. 3.5.5), RS 232C Operation (PAR. 3.5.6), fol-
lowed by a detailed explanation of SCPI programming (PAR. 3.6).
3.5.1 OPERATING FEATURES AVAILABLE ONLY BY REMOTE COMMANDS
The following paragraphs describe features of the BOP that are not available from the front
panel, but can be implemented using remote commands.
3.5.1.1 EXPANDED WAVEFORMS AND PROGRAMS
Refer to the documentation supplied with the VISA driver included with the BOP for more
detailed information regarding waveforms and programs, including examples of how to create a
table to load the variables.
3.5.2 PROGRAMMING TECHNIQUES TO OPTIMIZE PERFORMANCE
3.5.2.1 PROGRAMMING VOLTAGE/CURRENT LIMIT AND CURRENT/VOLTAGE LIMIT
Kepco's auto-crossover digital supplies can operate in either voltage mode with current limit, or
current mode with voltage limit. The operating mode is determined by the voltage and current
commands received, as well as the load. Each time voltage and current commands are
received, the unit must evaluate the commands and the load conditions to determine the neces-
sary operating mode. Reducing the number of times this evaluation must be made is desirable
because Kepco's digital auto-crossover supplies employ two separate feedback loops. Each
time there is a potential mode change, there is always an uncontrolled period of a few millisec-
onds while the two feedback loops compete for control of the output. By changing only the
active parameter (e.g., voltage for voltage mode), there is no doubt as to what the operating
mode will be, so the unit is never uncontrolled, response is quick and no transients are possible.
Recommended programming techniques are:
1. Minimize programmed mode (voltage or current) changes. Unless absolutely required by the
test parameters, allow the power supply to automatically switch modes as determined by the
load. This will improve response time and reduce undesirable transients.
2. Once the mode (voltage or current) is programmed, program the active parameter to zero
and the complementary limit parameter to the maximum anticipated for application. Then
program only the active parameter. The active parameter is the parameter that controls the
output, e.g., voltage controls the output in voltage mode.
3. Never program both the active and complementary limit parameter to zero. This can result in
long response times. Set the active parameter to zero and the complementary limit parame-
ter to a minimum, e.g., 10% of maximum, to ensure that the active mode is defined.