Faria Tachometer wiring

[Cat-a-tonic]

I have a Faria Tachometer wired into my boat with signals from the alternator to the SIG terminal. The other terminals are BAT (12V), GND and a spade terminal for lighting.


There is also what appears to be some sort of resistor bridging between SIG and BAT. Zoom the attached photo to see the the green blob. Can anyone explain the function of this bridge? The Tacho has been working with this configuration (until the needle stuck) but I would like to understand it better.

[ranger58sb]

We had Faria tachs on a previous boat. No resistor like that.

FWIW, signal to our unit was from the shaft, not the alternator... so maybe that's a difference. Also, I've read dual-station installations may use a different model of tach... but perhaps a resistor in there somewhere could accomplish the same thing.

At the time, Faria offered repair services. Our models incorporated an engine hour display, and the Faria repair process erased previously elapsed hours. (Lauderdale Tach, or some such, might have had a better process for that... can't remember...)

-Chris