4 June 15

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Yesterday we went to Sandvik for a tour of the facilities in Fairlawn. They also brought along their NHRA Top Fuel Dragster and its team and driver. We were given demonstrations on the CNC tools and high precision drilling as well as techniques used for high speed milling. On Tuesday we have a minor incidence with a beagleboard. We overloaded one of the input pins and that somehow has Bricked the board. Unfortunately some of our new programs were on the board, however most of our important code was saved to Github. We were trying to read serial GPS data from the sensor so only that code was lost. Today we received our thermistors so today we will be learning about thermistors and how to use their values to obtain temperature. Our goal is to have a program that will be able to read temperature from the thermistor resistance by the end of the day.

Thermistor Data:

Resistance 1,000 Ohm
Tolerance ±10.0%
Accuracy 25 °C [77 °F]
Beta 3348
Operating Temperature -60 °C to 300 °C [-76 °F to 572 °F]
Diameter 2,0 mm [0.080 in]
Termination Material Tinned copper-clad steel
Lead Length 28,6 mm [1.125 in]
Time Constant in Air 4.0 s
Dissipation Constant 2,5 m/W°C
Series Name 135
Curve

From Adafruit:
Where T is the measured temperature, T naught is room temperature in Kelvin (298.15), B is the beta value above, R naught is the resistance above, and R is the measured resistance.

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