5 watt solar panel

Thom1961 wrote:
So what I am hearing is essentially this: I wasted my money on that 5 watt panel.

YES

Of course my question wasn't about how effective this tiny panel was going to be, but rather which battery(ies) it would "charge".

It is impossible to answer this without being there to trace the wires.

Even if it was OEM, owners tend to change things to make them "better".

So what I am hearing is essentially this: I wasted my money on that 5 watt panel.
Of course my question wasn't about how effective this tiny panel was going to be, but rather which battery(ies) it would "charge". Even so, thank you for those who answered. I know there is a lot of knowledge in this group collectively.

Thomas Reynolds

Since it's there and you paid for the replacement, just let it do it's thing. As mentioned, it's usually hooked up to the chassis battery as that tiny amount of amperage would do nothing at all for your house batteries.

Thom1961 wrote:
I do realize that this is a "trickle" type charge ..

It's barely even that.

DrewE wrote:

Five watts is not very much power. It may well not be enough to overcome even the battery's self discharge, to mention nothing of any parasitic loads. I would not expect very much at all out of it.

THIS. Not worth the trouble I think.

Most of the 5 watt ones are to help maintain the chassis battery while parked. Think of it as a built in battery tender. Even then it's only a small supplement.

Most of them that I'm familiar with are 8 watts. That is 0.667 amps in strong sunlight. Worthless.

To see if it's doing anything, unplug from shore power. Wait 20 minutes for surface charge to drop to normal. Disconnect the battery negative and measure the voltage. Reconnect the battery negative while there's nice strong sunlight. Measure the voltage across the 12 V battery (or batteries).

If it's over 13V, it's actually doing something! Most likely though, it'll just be 0.2 to 0.4 volts over the voltage you measured previously.

Reconnect shore power. Measure the chassis battery voltage. Is it higher now? Than your RV has a Trik-L-Start or similar device and will keep your chassis battery charged when you plug into shore power...and the alternator will do that on the road. If it stays the same, or slowly drops, you should consider that device to keep your chassis battery charged. The solar panel won't do much in fighting all the parasitic loads normally on that battery.

My 5 watt solar panel is also on top of A/C...it makes a good flat spot for birds to land. Didn't do much else. Mine glows red also. I think it was put in to power some alarm if battery ever went all the dead.

Probably the chassis battery, but there's no way to be sure without tracing the wires or making some voltage measurements.

Five watts is not very much power. It may well not be enough to overcome even the battery's self discharge, to mention nothing of any parasitic loads. I would not expect very much at all out of it.