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Michael A. Terrell Michael A. Terrell is offline
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Default lighted switch help


"Dave Plowman (News)" wrote:

In article ,
Michael A. Terrell wrote:
What is the rated power output of the power supply? If it's a small
one only feeding a pre-amp it likely can't drive the 5 watt or so lamp
in the switch. Which could take over 500mA at switch on. A better
choice would be an LED - only about 20mA or so.

Generally car stuff like this isn't too concerned about efficiency.


Did you look at the link? There is no way the lamp is 5 watts. It
would melt the switch's body. It should be 10 to 50 mA. Think 'Grain
of Wheat' lamp.


Whatever. But the principle remains - filament lamps have a high start up
current which could be too great for a small regulated supply.



Where did he say the supply was that small? If it won't handle the
preamp & the lamp at the same time its too damn small, anyway. Even
small wall warts start around 200 mA.


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