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| {{zip|ArduinoAmmeter.zip|112KB|Version from 05.02.2012}} | | {{zip|ArduinoAmmeter.zip|112KB|Version from 05.02.2012}} |
| + | |
| + | ==Resistor Values== |
| + | The values of the given resistors are in the breadboard |
| + | picture |
| + | (from left to right) 100K 10K, 0.47 Ohm, 220 Ohm, 100K, 2.2K (twice). |
| + | Henceforth, I refer to them as R1, R2, R3, R4, R5, R6 und R7 respectively, |
| + | |
| + | With those given values a maximum voltage of 55 Volt and |
| + | a maximum current of 10.6 Ampere can be measured. For different voltages |
| + | choose a differnt R2, für different currents a different R3. |
| + | |
| + | Following table lists different values of R2 and its corresponding maximum voltage; |
| + | for differnt values of R3 its maximum current. |
| + | Note that R2 and R3 can be chosen independently from |
| + | each other. |
| + | |
| + | {| class="wikitable" |
| + | |- |
| + | ! R2 !! U_max !! !! R3 !! I_max |
| + | |- |
| + | | 50K || 15V || || 0.47 Ohm || 10.6A |
| + | |- |
| + | | 10K || 55V || || 4.7 Ohm || 1060mA |
| + | |- |
| + | | 6.8K || 79V || || 47 Ohm || 106mA |
| + | |
| + | |} |
| + | In case you choose a different value you have to adapt that in the Arduino source, respectively, |
| + | Regarding R2, modify the initialization of variable V10K_RESISTOR, |
| + | for R3 the variable I0_47_RESISTOR. |
| + | |
| + | The value of the resistors R6 und R7 (here given as 2.2K) need not to be exactly like that, |
| + | for instance a value of 4.7K worked as fine. There is nothing to adapt in the code in this case. |
| + | |
| ==Logging== | | ==Logging== |
| [[Image:DS1307.jpg|thumb|timer DS1307]] | | [[Image:DS1307.jpg|thumb|timer DS1307]] |