Question about Gauges

[mav6759]

Ok, I was replacing some wiring on my boat. And all of my gauges were working except for the tach. I removed all the gauges to clean all the contacts and make sure I had clean connection. When I was replacing the gauges, I noticed that my voltage gauge did not work anymore. I was getting power to the gauge and had a good ground. I could not figure out why the gauge wasn't working.. Then I was told by a older guy that if I tighten the center bracing nut to tight, it will peg the needle. (Its raining here now can't test the theory). But wanted to know if anyone heard anything about, if you tighten the center nut of the gauges in the instrument panel to tight, it will peg the needles and they won't work.

 

[dingbat]

But wanted to know if anyone heard anything about, if you tighten the center nut of the gauges in the instrument panel to tight, it will peg the needles and they won't work.

In theory, it’s possible to distort the face of a cheap gauge enough to inhibit the free movement of the needle, but would not “peg” the gauges.

A more likely scenario is that you connected a wire to the wrong terminal

 

[sam am I]

So if the wires are all re-attached properly what else can happened is that when you tighten the nut/s up on the hookup studs, a stud can rotate.......If the stud rotates too far it can literally break a internal wire.

The studs, as we know are used as a feed-through electrical connections HOWEVER, internally on some manu's gauges, they use a ring lug (as opposed to a PCB trace) on these studs with a small gauge wire attached to tap off the Sig/Power/Gnd. As mentioned, when rotated too far and if the ring lug is rotating along with the stud , it can break those tiny hookup wires off at the ring lug.......Been there done that.

I reckon something similar could also happen with PCB's copper traces too but, would be less adapt to happen as the stud should just rotate about the pad BUT! Enough force could tear the traces ..........