Basic electrical question

[Jerry M.]

Finally finished installing the new (L/L) wiring harness in my '62. Final step was to hook up the small harness from the voltage regulator to the generator. Noticed with the negative battery cable still disconnected, the red 12v wire from the dash harness to the BATT terminal on the voltage regulator will still show 12v if grounded to the negative battery post itself. It will not show voltage if grounded to other grounding points such as intake manifold or valve cover bolts.

Is this normal?

Thanks in advance
Jerry M

[Rich G.]

Re: Basic electrical question

Sounds normal if I’m reading your post correctly. Without the negative post connected the only place where “ground is ground” is the battery terminal.

[Richard M.]

Re: Basic electrical question

Normal & expected.

Bat+ solenoid post Black lead goes to Ammeter input. Ammeter output Red goes to VR.

So you will read battery voltage, since the Red wire is connected to Bat+ post, through Ammeter, with negative meter probe at Bat-.

[Jerry M.]

Re: Basic electrical question

Thanks Rich and Rich. Just wanted to make sure what I was seeing was normal and correct.
Now I have to find the info I've seen on installing the recommended fusible link(s).

[Richard M.]

Re: Basic electrical question

Jerry, In the Sticky above, see this file....

1956 to 1962 Corvette Ignition Fuse and C1 Fuse Points - Mozzetta et al mod.pdf

You could add a fusible link at the starter Bat+ feed to the wiring between the Black feed and Solenoid+. But if it should ever fail, getting at it would require raising the car up and splicing a replacement in. A problem if on the road away from home.

A 30A fuse at the Ammeter input would prevent a catastrophic event at the main feed with similar protection as the fusible link at the Solenoid+ concept. Caveat being it won't protect the Black wire from Solenoid+ to the Ammeter, only a short in the main feed following the Ammeter. Like if the VR or Horn relay feed shorted, or if the VR was stuck "ON" in overcharge, etc. Or if you drop a tool and short the VR Bat+ to Ground like I did once on a '60. The 30A Fuse saved the engine harness.

e.g.
C1fusesRev2.jpg

Another protection factor would be to add fuses at Ign, Clock, and Lighter. I've used 15A fuses for those. This is discussed in the PDF above.

Rich

[Jerry M.]

Re: Basic electrical question

Thanks Rich