[TR] TR3 Cigarette Lighter Install

[Randall]

> Given the fact that it is two wire, is there still a concern 
> with grounding through the case/bracket?

Depends on the adaptor.  Safest thing is to check with a powered test lamp
or ohmmeter, for continuity between the mounting and either power lead.
Some do, some don't.

> Ia m assuming that I 
> keep the polarity the same and ground the positive.

Right.

> I assume I would tie into that with the negative lead from 
> the socket and then find a good spot to ground the positive 
> lead.

That's right.

> Given that, again, is there concern with the mounting? 

As above, you need to check whether your adaptor has the outer plug
electrically connected to the mounting.  If not, you are good to go.  If it
does, I'd suggest looking for one that doesn't.

> He also mentioned the need for a fuse. How do I determine a good size.

Ideally it should be sized to the wire gauge you use.  But 10 amps (American
rating) should do.  Your GPS should only take an amp or two maximum, but you
might want to power something else in the future.  If you think you might
want to use a cigarette lighter, then use heavier wire and a 20 amp fuse.

Randall