Thomas Ales [M S E]
72 lines
2.0 KiB
Python
Executable File
72 lines
2.0 KiB
Python
Executable File
#!/opt/srasenv/bin/python3
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"""
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Test temperature scaling calculations.
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"""
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import math
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# Constants
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ADC_TO_VOLTS = 0.000244140625
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STEINHART_A = 0.0011279
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STEINHART_B = 0.00023429
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STEINHART_C = 8.7298e-8
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def test_main_temp_calculation(raw_adc):
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"""Test main temperature calculation with different circuit assumptions."""
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print(f"\n{'='*60}")
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print(f"Testing Main Temperature with RAW ADC = {raw_adc}")
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print(f"{'='*60}")
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v_thermistor = raw_adc * ADC_TO_VOLTS
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print(f"V_thermistor = {v_thermistor:.6f} V")
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# Try different circuit configurations
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configs = [
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(10000, 5.0, "10kΩ series, 5V ref"),
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(10000, 3.3, "10kΩ series, 3.3V ref"),
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(100000, 5.0, "100kΩ series, 5V ref"),
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(10000, 2.5, "10kΩ series, 2.5V ref"),
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]
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for r_series, vref, desc in configs:
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print(f"\n{desc}:")
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print(f" R_series = {r_series} Ω, Vref = {vref} V")
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if v_thermistor >= vref:
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print(f" ERROR: V_thermistor >= Vref")
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continue
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r_thermistor = r_series * v_thermistor / (vref - v_thermistor)
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print(f" R_thermistor = {r_thermistor:.2f} Ω")
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if r_thermistor <= 0:
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print(f" ERROR: Invalid resistance")
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continue
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# Steinhart-Hart
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ln_r = math.log(r_thermistor)
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inv_t = STEINHART_A + STEINHART_B * ln_r + STEINHART_C * (ln_r ** 3)
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temp_k = 1.0 / inv_t
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temp_c = temp_k - 273.15
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print(f" ln(R) = {ln_r:.6f}")
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print(f" Temperature = {temp_c:.2f} °C")
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def test_current_scaling(raw_adc):
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"""Test current scaling."""
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print(f"\n{'='*60}")
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print(f"Testing Current Scaling with RAW ADC = {raw_adc}")
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print(f"{'='*60}")
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current = raw_adc * 12.0 * ADC_TO_VOLTS
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print(f"Current = {current:.6f} A")
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if __name__ == '__main__':
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# Test with the reported raw values
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test_main_temp_calculation(2)
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test_main_temp_calculation(3)
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test_current_scaling(0)
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test_current_scaling(100)
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test_current_scaling(4095)
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