KEPCO BOP-GL 1KW Operator Manual Firmware Ver.3.05 and higher - Manual (Page 82)

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BOP-1K-GL 022814
±voltage protection (±V Protect) can be set to. If the programmed values are exceeded, a com-
mand error -201, Voltage Range error” occurs.
+V Protect and –V Protect are programmed using the VOLT:PROT commands (see PAR’s. B.29
through B.36 for details.) These commands program the ±voltage protection values. If load volt-
age reaches the ±voltage protection values, voltage will be clamped so ±voltage protection val-
ues cannot be exceeded.
3.5.5 PROGRAMMING TECHNIQUES TO OPTIMIZE PERFORMANCE
3.5.5.1 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 will go to the corresponding mode (voltage or current) with either the main
channel or the limit channel in control of the output (voltage or current), depending on the load
value. Each time there is a potential mode change, there is always an uncontrolled period of a
few fractions of milliseconds 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.
3.5.5.2 MAKING SURE THE PREVIOUS COMMAND IS COMPLETE
Some SCPI commands require a flash memory update and can take an indeterminate amount
of time to complete. These commands are:
• *SAV
• MEM:PACK
• MEM:UPD
• CAL:COPY
• CAL:SAVE
• SYST:PASS:NEW
• SYST:SEC:IMM
When sending these commands via the GPIB, these commands require a query to be added to
the command string to verify the previous command is complete. When the command is com-
plete, the unit updates the status byte and indicates MAV (Message Available, bit 4 - see Table
A-3) is true. MAV indicates that there is a response to be received by the computer, so when it