Diy power supply from an old computer psu: Difference between revisions
From wikiluntti
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=== The Fake Load === | === The Fake Load === | ||
10W 10Ω resistor between 5V (red) and GND lines. | 10W 10Ω resistor between 5V (red) and GND lines. The power resistor will give off a lot of heat and should be mounted on the metal wall for proper cooling (or a heat sink mount). | ||
Consider using a lighted 12v switch, which will act as the load necessary to turn on the power supply, or replace the 10W power resistor with the cooling fan that was originally inside the PSU, be careful with the polarity though - match the red and black wires to each other. | |||
== References == | == References == | ||
Revision as of 08:50, 11 June 2023
Introduction
Theory
12 V and 5 V.
Current
Wire Coloring
- Black: Ground (0V)
- Orange: +3.3V
- White: -5V
- Red: + 5V
- Purple: +5V standby
- Blue: -12V
- Yellow: +12V
- Grey: power is on indicator
- Green: ON/OFF switch; turn DC on by shorting to ground.
Power Switch
This system need to reverse the GND and 12V line.
- Yellow cable (12V) on the colored terminal,
- a black wire (GND) to the pin opposite,
- the green cable (ON/OFF) to the centre pin.
In normal operation illuminated SPST switches have 3 terminals
- the centre pin: green Power ON/OFF
- one is indicated either by a different colour or labelled GND.
- The terminal opposite would normally be wired with 12V,
The Fake Load
10W 10Ω resistor between 5V (red) and GND lines. The power resistor will give off a lot of heat and should be mounted on the metal wall for proper cooling (or a heat sink mount).
Consider using a lighted 12v switch, which will act as the load necessary to turn on the power supply, or replace the 10W power resistor with the cooling fan that was originally inside the PSU, be careful with the polarity though - match the red and black wires to each other.
