You need to determine what voltage you want for absorption and how long the regulator stays in the absorption stage to fully charge your bank. The battery types above show recommended absorption voltages, but the time depends on your bank size, depth of discharge, and alternator output.
It is not really a smart regulator, just a multi-stage regulator. It charges in bulk mode until the battery voltage rises to the absorption voltage. It stays at the absorption voltage for a preset time which you set by reading the voltage at the time test-point. Regardless of the state of charge, the regulator will drop to float voltage at the end of that time period, but the bank may not be fully charged.
For example: I have a 700 amp-hour bank with a 105 amp alternator and I routinely draw about 125 ah overnight. The system bulk-charges at 70A for around an hour then enters the absorption stage. At the factory setting of one hour in the absorption stage my bank will be fully charged at some point between 1 and 2 hours running time.
If however I discharge to 50%, 350 ah, the bulk phase will be longer, but the absorption phase will also need to be longer to fully charge the bank. How much longer? 120 minutes works for my system, might be just a bit undercharged but solar makes it up.
A state-of-charge monitor can help with determining the time requirement for your bank and your usage.
The absorption voltage is adjusted with the engine running, measured at the battery terminals.
Don’t disconnect the field. Disconnect the T+, which is the battery temperature sensor.
Sheet says factory setting is 14.4V absorption, float would be 13.6V.
Connect DVOM to battery, start engine, wait for continuous green light on regulator. Make small changes to Voltage adjustment screw, wait for results. Go slow and small.
Then check the time voltage reference and determine whether you need to change it.
