Home made Power supply unit.
This is my Home-made 50 amp Power supply, Its fixed voltage set for 13.8 volts dc , I built this supply a few years ago, Its really a hoch-potch of parts, Basically what i had to hand at the time. The Transformer cam from a Radio show, The Box i bought of a buddy, It originally had a 1.5 amp variable supply in it but it didnt work, The capacitor is 66,000 MF.
The supply has a soft start cicuit at switch on, This is Just a high wattage resistor in cucuit with the mains input, After a short time the relay energises ad the resistor is switched out of curcuit by the relay.
The supply also has proberbly the most important protection cucuit of all, A 'Over voltage' curcuit This uses the realy to switch of the mains and at the same time the capacior is shorted out by a resistor, For the Over voltage curcuit i use a Motorola MC3423 over voltage IC, The curcuit turns of the supply if it goes over 15 volts for any reason.
The supply also has a Thermally switched fan, There is a sensor on the heatsink, This monitors the temperature and tunrns the fan on and off.
I have a video of the supply on Youtube, Here is a link to it. http://www.youtube.com/watch?v=sM6CcxLuw90
The supply has a soft start cicuit at switch on, This is Just a high wattage resistor in cucuit with the mains input, After a short time the relay energises ad the resistor is switched out of curcuit by the relay.
The supply also has proberbly the most important protection cucuit of all, A 'Over voltage' curcuit This uses the realy to switch of the mains and at the same time the capacior is shorted out by a resistor, For the Over voltage curcuit i use a Motorola MC3423 over voltage IC, The curcuit turns of the supply if it goes over 15 volts for any reason.
The supply also has a Thermally switched fan, There is a sensor on the heatsink, This monitors the temperature and tunrns the fan on and off.
I have a video of the supply on Youtube, Here is a link to it. http://www.youtube.com/watch?v=sM6CcxLuw90