DEC standard power wire colour coding
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					DEC PDP-11's generally use a common system of colours in the power harness which leads from the power supply to the backplanes, etc.
It is:
| Line | Colour | 
|---|---|
| +20V | Orange | 
| +15V | Grey | 
| +15B (sometimes +12B) | White | 
| +5V | Red | 
| +5B | Red/white stripe | 
| Ground | Black | 
| -5V | Brown | 
| -15V | Blue | 
| -15B (sometimes -12B) | Green | 
| ACLO | Yellow | 
| DCLO | Purple | 
| LTC | Brown |