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Zeile 17:
{{zip|ArduinoAmmeter.zip|112KB|Version from 05.02.2012}}
{{zip|ArduinoAmmeter.zip|112KB|Version from 05.02.2012}}
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==Resistor Values==
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The values of the given resistors are in the breadboard
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picture
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(from left to right) 100K 10K, 0.47 Ohm, 220 Ohm, 100K, 2.2K (twice).
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Henceforth, I refer to them as R1, R2, R3, R4, R5, R6 und R7 respectively,
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With those given values a maximum voltage of 55 Volt and
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a maximum current of 10.6 Ampere can be measured. For different voltages
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choose a differnt R2, für different currents a different R3.
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Following table lists different values of R2 and its corresponding maximum voltage;
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for differnt values of R3 its maximum current.
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Note that R2 and R3 can be chosen independently from
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each other.
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{| class="wikitable"
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|-
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! R2 !! U_max !! !! R3 !! I_max
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|-
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| 50K || 15V || || 0.47 Ohm || 10.6A
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|-
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| 10K || 55V || || 4.7 Ohm || 1060mA
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|-
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| 6.8K || 79V || || 47 Ohm || 106mA
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|}
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In case you choose a different value you have to adapt that in the Arduino source, respectively,
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Regarding R2, modify the initialization of variable V10K_RESISTOR,
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for R3 the variable I0_47_RESISTOR.
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The value of the resistors R6 und R7 (here given as 2.2K) need not to be exactly like that,
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for instance a value of 4.7K worked as fine. There is nothing to adapt in the code in this case.
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==Logging==
==Logging==
[[Image:DS1307.jpg|thumb|timer DS1307]]
[[Image:DS1307.jpg|thumb|timer DS1307]]