Automatic 12V Lead Acid Battery Charger
R2 will have to be adjusted to set the proper finish charge voltage. Flooded and gel batteries are generally charged to 13. 8V. If you are cycling the battery (AGM or gel) then 14. 5V to 14. 9V is generally recommended by battery manufacturers. To set up the charger, set the pot to midway, turn on the charger and then connect a battery to it`s output
. Monitor the charge with a voltmeter until the battery reaches the proper end voltage and then adjust the pot until the LED glows steadily. The charger has now been set. To charge multiple battery types you can mount the pot on the front of the case and have each position marked for the appropriate voltage. # T1 is a transformer with a primary voltage appropriate to your location (120V, 220V, etc. ) and a secondary around 12V. Using a higher voltage secondary (16V-18V) will allow you to charge 16V batteries sometimes used in racing applications.