Trying to figure out these thermistor tables...? October 02, 2012 11:56PM |
Registered: 12 years ago Posts: 160 |
// Thermistor lookup table for two different thermistors. /* This table doesn't depend on the type of electronics, but on the type of thermistor(s) you use. You want one table for each thermistor type you use. */ // How many thermistor tables we have. #define NUMTABLES 2 // Names for our tables, so you can use them in config.h. // Table numbering starts at 0. #define THERMISTOR_EXTRUDER 0 #define THERMISTOR_BED 1 /* You may be able to improve the accuracy of this table in various ways. 1. Measure the actual resistance of the resistor. It's "nominally" 4.7K, but that's ± 5%. 2. Measure the actual beta of your thermistor: [reprap.org] 3. Generate more table entries than you need, then trim down the ones in uninteresting ranges. In either case you'll have to regenerate this table with createTemperatureLookup.py, which requires python, which is difficult to install on windows. Since you'll have to do some testing to determine the correct temperature for your application anyway, you may decide that the effort isn't worth it. Who cares if it's reporting the "right" temperature as long as it's keeping the temperature steady enough to print, right? */ // The number of value pairs in our table. // Must be the same for all tables. #define NUMTEMPS 49 uint16_t const temptable[NUMTABLES][NUMTEMPS][2] PROGMEM = { // Table for the Extruder. // EPCOS 100K Thermistor B57540G0104F000 // Thermistor lookup table for RepRap Temperature Sensor Boards (http://reprap.org/wiki/Thermistor) // Made with the online thermistor table generator by nathan7 at [calculator.josefprusa.cz] // r0: 100000 // t0: 25 // r1: 0 // r2: 4700 // beta: 4066 // max adc: 1023 { {1, 841}, {22, 328}, {43, 272}, {64, 243}, {85, 224}, {106, 209}, {127, 198}, {148, 188}, {169, 180}, {190, 173}, {211, 167}, {232, 161}, {253, 156}, {274, 151}, {295, 147}, {316, 142}, {337, 138}, {358, 135}, {379, 131}, {400, 128}, {421, 124}, {442, 121}, {463, 118}, {484, 115}, {505, 112}, {526, 109}, {547, 106}, {568, 103}, {589, 100}, {610, 97}, {631, 94}, {652, 91}, {673, 88}, {694, 85}, {715, 82}, {736, 79}, {757, 76}, {778, 73}, {799, 70}, {820, 66}, {841, 62}, {862, 58}, {883, 54}, {904, 49}, {925, 44}, {946, 37}, {967, 30}, {988, 19}, {1009, 1}, }, // Thermistor table for the Heatbed. // The thermistor used for this table was an NTC b4400 100k // Thermistor lookup table for RepRap Temperature Sensor Boards (http://reprap.org/wiki/Thermistor) // Made with the online thermistor table generator by nathan7 at [calculator.josefprusa.cz] // r0: 100000 // t0: 25 // r1: 0 // r2: 4700 // beta: 4400 // max adc: 1023 { {1, 649}, {22, 285}, {43, 240}, {64, 216}, {85, 200}, {106, 188}, {127, 178}, {148, 170}, {169, 163}, {190, 157}, {211, 151}, {232, 147}, {253, 142}, {274, 138}, {295, 134}, {316, 130}, {337, 127}, {358, 123}, {379, 120}, {400, 117}, {421, 114}, {442, 111}, {463, 109}, {484, 106}, {505, 103}, {526, 101}, {547, 98}, {568, 95}, {589, 93}, {610, 90}, {631, 88}, {652, 85}, {673, 83}, {694, 80}, {715, 77}, {736, 74}, {757, 72}, {778, 69}, {799, 66}, {820, 62}, {841, 59}, {862, 55}, {883, 51}, {904, 47}, {925, 42}, {946, 36}, {967, 29}, {988, 19}, {1009, 3} } };
Re: Trying to figure out these thermistor tables...? October 06, 2012 03:40PM |
Registered: 13 years ago Posts: 1,780 |
Re: Trying to figure out these thermistor tables...? October 07, 2012 03:57AM |
Registered: 12 years ago Posts: 160 |
Re: Trying to figure out these thermistor tables...? October 07, 2012 09:30AM |
Registered: 13 years ago Posts: 1,780 |
Re: Trying to figure out these thermistor tables...? October 07, 2012 06:54PM |
Registered: 12 years ago Posts: 160 |