Power Supply Control Example
Control a GW Instek GPD-4303S power supply using PyVISA to set voltage, current, and monitor operating modes.
This Python script uses PyVISA to control a GW Instek GPD-4303S power supply. It sets a voltage and current limits for two channels, reads their output values, and determines their operating modes (CV or CC). The interface here is Serial over USB.
import pyvisa
import time
# Create a resource manager
rm = pyvisa.ResourceManager()
# Connect to the power supply (update the VISA address as needed)
ps = rm.open_resource("ASRL/dev/ttyUSB0::INSTR",
baud_rate=115200,
write_termination="\\n",
read_termination="\\r\\n")
try:
# Print the power supply model
model = ps.query("*IDN?")
print(f"PSU model: {model}")
# Set voltage and current limits for channels 1 and 2
ps.write("VSET1:10.0") # Set CH1 voltage to 10V
ps.write("ISET1:0.5") # Set CH1 current to 0.5A
ps.write("VSET2:19.0") # Set CH2 voltage to 19V
ps.write("ISET2:0.1") # Set CH2 current to 0.1A
# Turn output on
ps.write("OUT1")
# Wait 2 seconds
time.sleep(2)
# Read voltage and current values
voltage1 = ps.query("VOUT1?")
voltage2 = ps.query("VOUT2?")
current1 = ps.query("IOUT1?")
current2 = ps.query("IOUT2?")
# Print voltage and current values
print(f"Channel 1: {voltage1} V, {current1} A")
print(f"Channel 2: {voltage2} V, {current2} A")
# Check if CH1 is in CC or CV mode
status = ps.query("STATUS?")
# Remember that all commands return strings
ch1_mode = "CV" if status[0] == '1' else "CC"
ch2_mode = "CV" if status[1] == '1' else "CC"
# Print channel modes
print(f"Channel 1 is in {ch1_mode} mode")
print(f"Channel 2 is in {ch2_mode} mode")
# Turn output off
ps.write("OUT0")
finally:
# Close connection
ps.close()
rm.close()How is this guide?
