Solar trickle charger

[BPeschka]

I’m looking on Amazon at solar trickle chargers / battery maintainers. For 12volt products, I see specs of 3, 5, 10 watts, among others. I’m wanting to maintain the vehicle battery for a Ford E350, not a multi battery house setup.

Does anyone know if 3 or 5 watts is enough? I live in AZ so have plenty of solar available. Thanks.

[Chuck v]

The chassis electronics on a modern truck like the Ford 350 series have a baseline 'parasitic' drain of about 80 to 100 milliamps (about 1.2 watts or less in a 12 volt system...) so small solar panels will do a fair job of maintaining a battery in this case, but if you leave anything else on in the vehicle, the solar charger cannot keep up. I would use a 10 watt panel at least, because the drain is 24 hours a day but the solar replenishment is about half of that time frame so it needs to be enough to carry through the night. If you are trying to recharge the battery after a trip, you need at least a 6 amp charging source (75 watt solar panel...) With solar, more is always better.



Chuck

[BPeschka]

Thx, Chuck