# Model an NTC thermistor with the B parameter equation # Copyright (C)2024, Philip Munts dba Munts Technologies. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # * Redistributions of source code must retain the above copyright notice, # this list of conditions and the following disclaimer. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE # POSSIBILITY OF SUCH DAMAGE. __author__ = "Philip Munts " from math import exp, log class Model: # Constructor def __init__(self, B, R0, T0 = 25.0): # Celsius self.B = B self.R0 = R0 self.T0 = T0 + 273.15 # Kelvins # Calculate Kelvin temperature as a function of thermistor resistance def Kelvins(self, R): return self.B/log(R/self.R0/exp(-self.B/self.T0)) # Convert to Celsius def Celsius(self, R): return self.Kelvins(R) - 273.15 # Convert to Fahrenheit def Fahrenheit(self, R): return 1.8*self.Celsius(R) + 32.0