The concept of the project is taking a power source measuring 51.8VDC and 23.8mA, and using this to operate multiple small fans. The fan I have chosen is battery operated by 2 Dcell batteries. I have a limited physics based understanding of circuits, but unfortunately my math isnt translating well to realworld applications.
I have attached a photo of some concept circuits, and associated thoughts about each. The first hurdle I encounter is: What current is really needed to run this fan? Theres a port for an AC adapter that says 3VDC, 500mA, however Im obviously getting no where near 500mA on 2 batteries. With my trusty multimeter I measure a total of 2.4Ohms of resistance through the fan, and 3.4V / 8.6mA on a pair of new batteries. This doesnt make sense to my limited V=IR education.
The second hurdle is using resistors. I thought in a series circuit that current remain constant and voltage dropped across resistors, however upon adding a resistor between my meter and the power source I noticed a drop in voltage, but also a significant drop in current. Hence by the time I apply enough resistors to get down to 3V, I have no current left.
I know there are several components out there (voltage regulators, diodes, etc..) that I probably need, but these are beyond my basic understanding. I would greatly appreciate any help, or anyone who could diagram the correct circuit to ideally power as many fans as possible given this fan and power source.
I have attached a photo of some concept circuits, and associated thoughts about each. The first hurdle I encounter is: What current is really needed to run this fan? Theres a port for an AC adapter that says 3VDC, 500mA, however Im obviously getting no where near 500mA on 2 batteries. With my trusty multimeter I measure a total of 2.4Ohms of resistance through the fan, and 3.4V / 8.6mA on a pair of new batteries. This doesnt make sense to my limited V=IR education.
The second hurdle is using resistors. I thought in a series circuit that current remain constant and voltage dropped across resistors, however upon adding a resistor between my meter and the power source I noticed a drop in voltage, but also a significant drop in current. Hence by the time I apply enough resistors to get down to 3V, I have no current left.
I know there are several components out there (voltage regulators, diodes, etc..) that I probably need, but these are beyond my basic understanding. I would greatly appreciate any help, or anyone who could diagram the correct circuit to ideally power as many fans as possible given this fan and power source.
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