Difference between revisions of "electrical equations"
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The voltages are proportional to the resistances. | The voltages are proportional to the resistances. | ||
+ | <pre> | ||
Vout = Vin * (R2 / (R2 + R2)) | Vout = Vin * (R2 / (R2 + R2)) | ||
Vin = Vout * ((R1+R2)/R2) | Vin = Vout * ((R1+R2)/R2) | ||
+ | </pre> | ||
<pre> | <pre> |
Revision as of 07:05, 20 January 2014
P = E^2 / R
Contents
Voltage Divider
Voltage Divider No Load
The voltages are proportional to the resistances.
Vout = Vin * (R2 / (R2 + R2)) Vin = Vout * ((R1+R2)/R2)
Vout+ O Vout- O | | | | R1 | R2 | +--/\/\/--+--/\/\/--+ | | | | Vin+ Vin-
Voltage Divider Under Load
Rload +--/\/\/--+ | | | | Vout+ O Vout- O | | | | R1 | R2 | +--/\/\/--+--/\/\/--+ | | | | Vin+ Vin-
Vout = Vin (
Picking a value for R1 and R2
Assume you have a restive sensor to test. Out of circuit you would test the sensor to determine its minimum resistance and maximum resistance. Then pick
R2 = sqrt (Rmin * Rmax)