Need to make variable DC power supply 0 -100 v current 2 amps. With coarce snd fine addjustments for voltage with 3 1/2 digit meters for both volt and current
Hi Swatagam, could you please explain to me in detail the formula, resistance in parallel. I understand how to calculate for two resistors in parallel but don’t know how to calculate for more then two, beyond many textbooks just stating the formula as 1\R1+ R2+R3+R4…. Please detail this concept of reciprocals. P.s. I’m a hobbyist. Thank you very much for caring and sharing such a wonderful site. P.s. I’m a hobbyist.
Ksmani says
Need to make variable DC power supply 0 -100 v current 2 amps. With coarce snd fine addjustments for voltage with 3 1/2 digit meters for both volt and current
Swagatam says
If you use a linear approach, there will be a lot of heat dissipation. Better to use a transformer based design.
A linear design is shown below:
https://www.homemade-circuits.com/universal-variable-power-supply-circuit/
you can upgrade it to 100V by replacing the power transistors accordingly, and by changing R3 to 10K 1 watt
moboy says
Hi Swatagam, could you please explain to me in detail the formula, resistance in parallel. I understand how to calculate for two resistors in parallel but don’t know how to calculate for more then two, beyond many textbooks just stating the formula as 1\R1+ R2+R3+R4…. Please detail this concept of reciprocals. P.s. I’m a hobbyist.
Thank you very much for caring and sharing such a wonderful site. P.s. I’m a hobbyist.
Swagatam says
Thank you moboy, It is actually very basic, here’s the formula for calculating resistors in parallel:
1/R = 1/R1 + 1/R2 + 1/R3….1/Rn