Since my page was first posted, I have received a number of emails asking
about a high current power supply. I looked around, but couldn't find one that
was suitable. So, I designed this. It is a linear supply, which might have a few
of you rolling your eyes, but it takes very few parts, is simple to build and
can supply huge currents.
Schematic
Parts
|
Part |
Total Qty. |
Description |
Substitutions |
|
R1 |
1 |
680 Ohm 1/4 Watt Resistor |
|
|
C1 |
1 |
20,000 - 50,000uF 20-40 Volt Capacitor |
|
|
C2, C3 |
2 |
100uF 50 Volt Capacitor |
|
|
C4 |
1 |
0.1uF 50 Volt Capacitor |
|
|
C5 |
1 |
0.01uF 50 Volt Capacitor |
|
|
D1 |
1 |
Zener Diode (See Notes) |
|
|
Q1 |
1 |
2N3055 Or Other (See Notes) |
|
|
T1 |
1 |
Transformer (See Notes) |
|
|
BR1 |
1 |
Bridge Rectifier (See Notes) |
|
|
S1 |
1 |
SPST 250 VAC 10 A Switch |
|
|
MISC |
1 |
Case, Line Cord, Heatsink For Q1, Binding Posts For Output |
|
Notes
1. D1 should be rated at about one volt higher than then desired output of
the supply. A half watt diode will do.
2. Q1 can be a transistor similar to the 2N3055. I chose the 2N3055 for it's
availability and power handling (150 watts).
3. 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.
4. 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.
5. The value of R1 will be smaller when supplying high currents. Expiriment
until you get what you need.
6. Heatsink and fans are absolutely necessary!