Normally, the side of the ammeter opposite the single wire that goes to the battery cable connection at the starter will have several wires attached to it- - - -light switch, ignition switch, fuse box, and any other circuit that needs unswitched battery voltage. Some ammeters have a longer stud on that side to accommodate several ring terminals. Connected that way, any current in or out of the battery can be monitored by the ammeter. As long as the charging system is producing more current than the sum of all the loads, the ammeter will show a charge. If the load exceeds the charging system output, a negative flow will be indicated. The generator or alternator meets all the electrical demand first, and then uses its leftover output to charge the battery.
Jerry
