Can you leave your solar panel connected when not in use ?

[grassy]

There seems to be major myths around solar panels.

We have a solar panel on our 5th wheel trailer. When we put it in storage, we cover the solar panel and disconnect the batteries.

I have seen many trickle charges for car batteries used for keep up the battery while the car is stores.. so I am thinking...

Why can I not just turn off all the breakers inside the trailer..leave the solar panel hooked up and jsut pick it up 5 months later with freshly charged batteries..

What is the downside to having the solar panel keep the batteries charged all winter ?

Thanks..

[inetdog]

If you have a good charge controller with correctly set float voltage it should be fine.

[littleharbor]

If you have flooded batteries make sure to check the electrolyte level and top off if necessary. There are usually some small loads like smoke alarm, co2 sensor and maybe clocks that would be better off disconnected while your trailer is stored. Be sure to reconnect them when you begin the camping season. I would simply pull the fuses and leave the power center door open with the fuses lying there. This keeps your batteries from micro cycling and using up water in the batteries.

[grassy]

Many thanks.

Grassy

[solarix]

OMG, the solar is going to leak out on the ground!

[Sunking]

Why can I not just turn off all the breakers inside the trailer..leave the solar panel hooked up and just I pick it up 5 months later with freshly charged batteries..

You can and in fact is the way it is done.. Where did you get the idea you could not?

Make sure the batteries water level is full, and FLOAT set to the proper voltage, and you can leave them for a year if you want.

[grassy]

OMG, the solar is going to leak out on the ground!

You know, you can ghet help for that..don't wait until it is critical..

[grassy]

You can and in fact is the way it is done.. Where did you get the idea you could not?

Make sure the batteries water level is full, and FLOAT set to the proper voltage, and you can leave them for a year if you want.

The RV industry..myths abound..

When you say "float set" to the proper voltage..does this mean you can turn down the output of the cell ?

Thanks.

[PNjunction]

Sounds to me like your solar panel is a dinky auto-parts store type that doesn't have a charge controller. Your charge controller will have the float setting.

One "MYTH" that abounds is about not using a charge controller if your panel is tiny and your battery is large. That depends on the environment:

1) If your large battery is not fully charged, all the dinky panel without controller will do is slow down the self-discharge. It is too small to actually charge it to any reasonable degree, although it may attain a devilishly foolish "surface charge". So people think they can get away with no controller especially if it isn't stored long term.

2) If you DO already have a fully charged battery, and you put one of these controller-less panels on it, then you WILL destroy the battery. Despite the panel current output being nearly nothing, the VOLTAGE at the battery terminals will try to meet the controller-less voltage of the panel eventually- which is typically 18-22v. This high-voltage situation will just corrode and eat up your positive plates first even though no current seems to be flowing.

So - moral to the story - use a controller to cover ALL your bases. Or wing-it, and come back in 5 months to a damaged battery, by a dinky little panel believe it or not.

And remember the rule about connecting batteries to a controller FIRST, and the panel LAST. In some cases, controllers which don't see any voltage on their battery terminals, assume you have a ZERO-VOLT battery, and when the panel is connected first, will either refuse to charge this unsafe condition, (not knowing the difference between a battery that is missing to a zero-volt one!) or perhaps drop to a failsafe float, rather than their normal CC/CV routine.

[grassy]

Best guess - 100 to 160 watt...is this dinky ? It was on the rig when I bought it.

I didn't say I didn't have a float setting, I said I have no idea what it is. I have a control panel which shows a bunch of its functions however, it is strictly display..

Quite frankly, this panel is irrelevant to me.. we haven't boon docked for ages and the batteries in my TV are big so overnighting once in a while is all we do..

[PNjunction]

Ok, no problem. That system is more of a very big maintainer than anything else.

By all means leave it hooked up in the winter - provided you check on the batteries once in awhile and not just total abandonment. Leaving the panels disconnected won't hurt either, as long as you have a secondary charge source to keep the batteries topped off to avoid sulfation. You'll want to match the controller specifications to match those of the batteries - and ideally with "at the battery" temperature compensation to do it right.

Tip: If you haven't done so, crawl up top and look inside the junction box. Make sure the connections are clean and tight. Some RV'ers I know skip this important maintenance step every year or so, not realizing that the thermal expansion/contraction over time can loosen the connections inside the junction box. This can make for high-resistance contacts for the internal bypass diodes, which get hot enough in normal use, and can fail.

[grassy]

Many thanks...I will pass this info along to others with the same question. Ypu have been a great help.

grassy..