Python-script-for-load-transient-test/Program file.py at main · Malegowda1/Python-script-for-load-transient-test · GitHub

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# Automated Load Transient Test
import pyvisa            # Instrument communication
import time              # Delay & timestamps
import csv               # CSV logging
from datetime import datetime


# Test Parameters
INPUT_VOLTAGE = 5.0
LOAD_LOW = 0.5            # Amps
LOAD_HIGH = 2.0           # Amps
STEP_TIME = 0.01          # 10 ms
MAX_UNDERSHOOT = 0.2      # Volts (200mV)
MAX_OVERSHOOT = 0.2

CSV_FILE = "load_transient_results.csv"

# Connect to Instruments

rm = pyvisa.ResourceManager()

psu = rm.open_resource("USB0::PSU_ADDRESS::INSTR")
eload = rm.open_resource("USB0::ELOAD_ADDRESS::INSTR")
scope = rm.open_resource("USB0::SCOPE_ADDRESS::INSTR")

print("Instruments connected")

# Configure Power Supply

psu.write("VOLT {}".format(INPUT_VOLTAGE))
psu.write("OUTP ON")

# Configure Electronic Load

eload.write("MODE CC")              # Constant Current
eload.write("CURR {}".format(LOAD_LOW))
eload.write("INPUT ON")

# Configure Oscilloscope

scope.write("TIM:SCAL 1E-3")         # 1ms/div
scope.write("TRIG:EDGE:SOUR CH1")
scope.write("TRIG:EDGE:LEV 3.0")

# Open CSV File

with open(CSV_FILE, mode="w", newline="") as file:
    writer = csv.writer(file)
    writer.writerow([
        "Timestamp",
        "Undershoot (V)",
        "Overshoot (V)",
        "Pass/Fail"
    ])

    # Run Load Transient Test
    print("Starting load transient test")

    # Apply high load
    eload.write("CURR {}".format(LOAD_HIGH))
    time.sleep(STEP_TIME)

    # Return to low load
    eload.write("CURR {}".format(LOAD_LOW))
    time.sleep(0.05)

    # Measure using Scope

    undershoot = float(scope.query("MEAS:VMIN? CH1"))
    overshoot = float(scope.query("MEAS:VMAX? CH1"))

    # Pass / Fail Decision

    if abs(undershoot) <= MAX_UNDERSHOOT and abs(overshoot) <= MAX_OVERSHOOT:
        result = "PASS"
    else:
        result = "FAIL"

    timestamp = datetime.now().strftime("%Y-%m-%d %H:%M:%S")

    # Log to CSV
    writer.writerow([
        timestamp,
        undershoot,
        overshoot,
        result
    ])

    print("Test Result:", result)

# Turn OFF Instruments
eload.write("INPUT OFF")
psu.write("OUTP OFF")

print("Test completed")