I finally got my instrument cluster installed; have the 1950 repo manual, I've converted to 12 volt because I have 1990 Crown vic donor, so.....

I need insight on wiring in the ammeter (not stock; from 1989 Econoline Van) , so it reflects total current draw on the electrical systems. My thoughts are to source 30 Amp circuit from my fuse panel, which is only hot when ignition key is on; to feed to the original 30 amp breaker attached to the instrument cluster, which in turn will feed series power to the instrument gauges. Do I have to parallel the other loads, in order to get a true draw through the ammeter.

Julie , the clock is ticking. I do have the period wiring diagrams, but obviously with 12 volt this will vary a bit.

Come back.

 

Being 6 or 12 volt isn't as crucial as how you are flowing your power distribution, and how you are running your charging circuit (Alternator? Generator?). You can't use the existing breakers on the panel, they are for 6 volt.

You should have your generator/alternator charge going straight into your hot fuse panel (for items that are powered all the time - ie headlights, brake lights, horns, courtesy lights, etc) - then up to "BATT" stud on the ignition switch. From there up through the ammeter then out to the battery cable post of the starter solenoid.



The power going to a second fuse panel for the items that come on with the ignition should come down from the "ACC" post of the ignition switch. The gauge will only show an accurate charge or discharge if it has power flow capability from both sides generator/alternator on one side and battery on the other.

Here's a drawing that wil help you hook up the actual amp gauge if it's not the traditional induction loop:

 

I'll have to study this wiring for a while, til I can get back on the wiring next week.

Working at aligning front sheet metal, am so close....

Later

Tom

 

the problem with the Ammeter approach is that ALL the power has to go THRU the gauge, before it goes anywhere else..

the new voltage meters don't need to do that.. (and why they were built really, to stop having to drag ALL the power to the dash area

sam

 

Tom, just a quick heads up, you ammeter isn’t, it’s a volt meter calibrated to read in amps. It should be wired in parallel, just wired to 12v hot / switched and ground not in series with everything going thru it.

Julie, I did not read your complete post, no time this AM, so you might have said that, just wanted to catch Tom before the fire!

 

Just kiddin; I'm going to do a little more research on the donor wiring schematics, but definitely won't be loading the meter in series now, thanks