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Unread 16-12-2008, 15:34
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Re: New Power Distribution/ Fuse Pannel Problem

Quote:
Originally Posted by mole View Post
Perhaps I can clairfy.

The battery voltage is 12 volts from the mains, going into the PD board. When you put the fuse in, the output from the terminal is 12 volts. However, when the fuse is removed, the output is STILL 12 volts.

It sounds to me like the board may indeed be faulty, as the output should be ZERO (I would think) after the fuse is removed. Otherwise, what is the purpose of a fuse if current/voltage is still allowed to pass through.
As Eric posted above you there is an internal connection between the battery input and the terminal outputs that bypasses the fuse through about 100kOhms of resistance.

This means that with no load, no current flows through that 100kOhms and you see the battery voltage at the output terminal even with no fuse in place. If a load is attached a very small amount of current will flow through this 100kOhms and the load and the 12V will be dropped across the 100kOhms (assuming the load resistance is << 100kOhms)

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