| An ammeter is generally placed in line between the battery and the loads & alternator (excluding the starter), to give an indication of whether current is leaving or entering the battery. This is a bit difficult to do on most vehicles, as power is taken from the large lug on the starter, and from the battery cable, near the battery. These circuits would have to be combined with the alternator charge wire & connected to one terminal of the alternator, while the other terminal of the alternator would have to be connected to the battery. Also, heavy 8 or 10 gauge wire would have to be routed into the passenger compartment, which is quite combersome. An easier solution would be to use a volt meter to give an indication of the status of the charging system.
Tim | 
