High Current Power Supply Circuit with 2N3055

This is a unregulated dc power supply circuit which have ability to handle high current load.

Component parts:

R1_________ 680 Ohm 1/4 Watt Resistor
C1_________ 20,000 - 50,000uF 20-40 Volt Capacitor
C2, C3_____ 100uF/50 Volt Capacitor
C4_________ 0.1uF 50 Volt Capacitor
C5_________ 0.01uF 50 Volt Capacitor
D1_________ Zener Diode
Q1_________ 2N3055 Or Other
T1_________ Transformer
BR1________ Bridge Rectifier
S1_________ SPST 250 VAC 10 A Switch
MISC_______ Case, Line Cord, Heatsink For Q1, Binding Posts For Output

NOTES:

D1 should be rated at about one volt higher than then desired output of the supply. A half watt diode will do.
Q1 can be a transistor similar to the 2N3055.
T1 should be about 5 volts higher than the desired output of the supply, and rated for about one amp more of current. The voltage overhead is required by the regulator section. The extra current is to keep the transformer from over heating.

The choice of BR1 will depend on the voltage and current of your transformer. The rectifier should be rated for 50 volts more than the transformer, and 5 amps more than the transformer.

The value of R1 will be smaller when supplying high currents. Expiriment until you get what you need.
You are going to need to heatsink Q1 and BR1. Use a small PC case style fan unless you are going to run large heatsinks.

Comments

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