Green wire on terminal 1 is the field supply. Regulator increases field current when it's voltage sense input is lower than the target voltage, and decreases field current when it's voltage sense is higher.
Brown and white on terminal 2 is voltage sense for the regulator. The regulator uses this to determine how much field current should be boosted or reduced to maintain the target voltage.
Terminal 3 is connected to battery, that is battery power source for the regulator. When the engine starts, the alternator spins, however, there's no field current until it can be sourced from somewhere... and Terminal 3 is where that comes from. The regulator draws it's field supply current through this terminal.
Terminal 4 is for a dash indicator, which is not used in this application.
The large orange wire coming from left terminal, is alternator output... it goes to the right side of the ammeter. With battery on the left terminal, whenever the alternator is not charging, the ammeter needle will indicate a discharge. When the alternator is charging, current flow will cause the ammeter needle to swing towards the charge side.
On the alternator, the remaining 'big' wire shown, is going to the GROUND terminal on the alternator case. This is a ground wire for the alternator's field, as it is not internally grounded. In most automotive applications, this connection is just internally grounded, but on heavy-duty/industrial type applications, it is not unusual to have a different regulation (where shunt resistance is AFTER, rather than BEFORE the alternator field) or a dual battery 12/24v system... in which case, this post is used in a different wiring scheme.
In the case of your new alternator, none of these connections except for the BATTERY connection is used, and the ground is connected to case internally.
Topic Options
Post Options
Thanks(0)
