Join Date: Mar 2002
Location: Austin, TX, USA
Re: Another CS130 alternator upgrade question
Sounds like you've got it wired up just fine. The 'L' wire is fed from the GEN lamp and serves two purposes. First, it excites (enables) the voltage regulator (on most anyway), and second it allows the regulator to show a failure by grounding the 'L' wire internally. Sounds like when your alternator failed, perhaps the regulator was toast and didn't have enough brian cells to ground the 'L' wire and light the light.
The 'S' terminal being hot all the time is normal. Sounds like you're aware that it's a voltage sense terminal. It's connected to battery power - typically at the main power distribution point. As a result, it will be hot always. Many folks connect the 'S' terminal directly to the B+ terminal on the back of the alternator which effectively disables the remote sensing feature altogether.
Connecting it to the horn relay buss bar would have been a better choice than the terminal block behind the battery IMHO. The horn relay is the main power distribution point and you want it to be well regulated. There will be a slight voltage drop between the battery terminal block and the horn relay, and that will show up as a slight change in system voltage depending on the load and charge rate. But in any event, I'm sure you're setup will perform better than the OEM mechanical regulator setup in terms of higher current capacity and better regulation.
68 Coupe, 350 w/ Edelbrock Performer RPM heads, cam, intake, 700R4, Dave's small body HEI