KEPCO KLP Series (older -1200 models) Operator Manual - Manual (Page 69)

KLP073008
3-29
3.7 REMOTE PROGRAMMING USING ANALOG SIGNALS
The voltage and current inputs (Vref and Cref, respectively) of the Analog I/O Port (see J2, Fig-
ure 2-2 and Table 2-2) are normally inactive. These are activated by connecting pin 12 of J2 to
one of the four GND pins: J2 pin 9, 11, 13 or 15 before turning the power supply on. Once the
power supply is turned on the status display reads aRem. While the power supply is in analog
remote mode, digital queries related to status and readback will be accepted and executed. The
following paragraphs provide detailed information for using analog programming signals.
NOTE: Optimum resolution is achieved with 10V programming input which is equivalent to full
scale. Decreasing the analog voltage equivalent to full scale (see PAR. 4.3.3) will
cause a corresponding decrease in programming resolution.
With the exception of Vref and Cref, all the other Analog I/O Port functions are active regardless
of the status of the analog control signal applied to J2 pin 12. These include internal relay:
RELAY_NO (pin 2), RELAY_COM (pin 4), RELAY_NC (pin 10); voltage and current readbacks:
VOLT_RBACK (pin 6) and CURR_RBACK (pin 7); external trigger: EXT_TRG (pin 14) and
remote inhibit: REM_INH (pin 8).
3.7.1 ENABLING/DISABLING THE OUTPUT USING ANALOG CONTROL
Enabling and disabling the output is accomplished via the analog I/O port using pin 8. Logic 0
(ground) turns the output off, Logic 1 (open) turns the output on.
FIGURE 3-5. TYPICAL EXAMPLE OF KLP POWER SUPPLY PROGRAM USING SCPI COMMANDS
/**************************************************************************/
/* 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
}