KEPCO BHK-MG 200W (Full Rack) Series - Manual (Page 75)

BHK-MG (OPR) 022014
3-31
FIGURE 3-6. TYPICAL EXAMPLE OF BHK-MG POWER SUPPLY PROGRAM USING SCPI COMMANDS
3.6 REMOTE PROGRAMMING USING ANALOG PROGRAMMING TERMINALS
The BHK-MG power supply is designed with separate, but similar, circuits for analog voltage
programming (Figure 3-7) and analog current programming (Figure 3-8). The voltage program-
ming circuit is used for programming output voltage if the unit is in voltage mode, or voltage limit
if the unit is in current mode. Similarly, the current programming circuit programs output current
in current mode, and current limit in voltage mode.
For each circuit, the digital programming section provides a voltage (DP (V) for voltage, DP (C)
for current), between zero and -10V d-c, applied to the input of a summing and correction ampli-
fier. This amplifier drives, in turn, the voltage error amplifier and the pass element to produce the
output. Each circuit also includes an uncommitted amplifier which can be configured to be
summed with the output of the digital programming section at the input of the summing and cor-
rection amplifier. Configuration of the uncommitted amplifiers is accomplished at the ANALOG
PROGRAMMING TERMINALS at the rear panel: VOLTAGE PROG. terminal strip TB2 for volt-
age, CURRENT PROG. terminal strip TB3 for current.
/**************************************************************************/
/* Sample Program For KEPCO power supply, using National Instruments */
/* GPIB interface card and IBM PC or compatible computer */
/**************************************************************************/
#include
#include "decl.h"
char rd_str[80]; // Input buffer
char dat_str[80]; // Output buffer
int bd,adr;
main() {
adr = ibfind("DEV6"); // Open DEV6 (defined by IBCONF)
bd = ibfind ("GPIB0"); // Open GPIB card
ibsic (bd); // Send Interface Clear
ibsre(bd,1); // Set remote line true
strcpy(dat_str,"VOLT 5;CURR 1"); // Define a set command
strcat(dat_str,"\r\n"); // Append delimiter
ibwrt(adr,dat_str,strlen(dat_str)); // Send string to power supply
strcpy(dat_str,"MEAS:VOLT?;CURR?"); // Define a measure command
strcat(dat_str,"\r\n"); // Append delimiter
ibwrt(adr,dat_str,strlen(dat_str)); // Send string to power supply
strset(rd_str,'\0'); // Clear input buffer
ibrd(adr,rd_str,64); // Read result of measure
printf("received : %s\n",rd_str); // Print voltage and current
}