Diy psu

[ktnch]

Got bored so made myself a 13.8v 50amp psu, with 3-30v 0-10amp adjustable psu, has 2 x usb 3amp outlets,

Just designing a reverse polarity protection board not just diodes and fuses thinking of an IRF53005PBF, using diodes there will be quite a lot of voltage drop

[ktnch]

Protection pcb

Mosfets are IRF53005PBF, rated at 55v and 31amp each, running two in parallel, some may notice the Drain and Source are reversed, This orientation is necessary so that the slight leakage current through the FET's intrinsic body diode will bias the FET on when the polarity is correct and block current when reversed, thus shutting off the FET, the gate voltage is kept down via the 10k resistor and the 10v zener diode, then on the output a 10uf 50v cap

[ktnch]

Going to add pwm fan cooling with temp readout, also thinking of touchscreen as the v2 model will see, also in the pipe line is an adjustable dc load/discharger with auto cut off

[stevec]

nice project.

are you using a shunt resistor on the amp meters?

I have one of those and was wondering what the maximum amps you can measure it without a shunt.

/Steve

[ktnch]

5-10 amp, the adjustable side is using on board shunt, the main power side external shunt