poll about ammeter reading

[383man]

Its like I tell people all the time who think if you put a 100 amp alt on a car that had a 40 amp alt that you will burn the wiring up. You can put a 300 amp alt on it and if you don't change the cars electrical system at all it wont burn up anything. The alt will only put out what the electrical system and battery demand and as soon as it does the regulator cuts it back to only what is needed. I have also seen a few battery's in my years take in many amps and not bring its voltage up and fool the tech. That's where I saw many techs put a voltmeter on the battery and say ….oh its only at 12.7 volts and they bypass the reg and its still the same. So they replace the alt and its still 12.7 volts because the alt is putting 30 amps into the battery but the volts wont come up and all they had to do was use an ammeter in the alt output wire to help diagnose a bad battery. Its rare but I have seen it about 3 or 4 times in my 40 years as a tech and its easy to get fooled since most of the time you can do a quick voltmeter across the battery and see if its charging and if the volts reads normal it is but I always like to put an ammeter on to check alt amps also if the voltmeter shows low volts at the battery when testing. Heck I even had a battery charged backwards by a Sears store that they sent to my dealer because it would not start after they replaced the battery on a mid 70's car. Funny as the cranked over backwards but the electronic ign would not fire until I put a properly charged battery in that did not send the volts down below 0 when the voltmeter was hooked up. You see some crazy things over the years that can make you bang your head sometimes. Ron

 

[Nacho-RT74]

North of center running.....

View attachment 981802

That's pretty much normal after crank up the engine and maybe for 5 to 10 minutes ( maybe even 20 minutes if took a lot to start up the engine or alternator is low amps ) while battery is getting back the juice lost when cranked up the engine, but if takes more than that there is something wrong there. Battery should get recharged after that and get a centered needle, with some ocasional and small flickering between D and C depending on loads and alt capacity and response.

Remember, NOTHING must be sourced from batt side of the ammeter. If yo do, will get that reading, which is not true and will be getting stressed the ammeter without need for that.

 

[Should be playing golf]

Ya, but I voted the most often!