Chinook RV

On our 2000 Concourse we have the original 50W (I think) solar panel on roof with the Magnatek controller. I would like to supplement the solar charging with a 100 watt "suitcase" style flexible solar panel with integrated charge controller. The new system is connected to the batteries with cables and clips directly to the batteries. Will there be an issue considering there will be two separate charges to the batteries? If so, what re-wiring might be necessary to integrate these two charging systems?

In a previous thread, I do see: " Since it is wired directly to the battery, it has nothing to do with the house system. Just can't charge batteries using both at same time." So I wonder why we can't use both at the same time...

Thanks in advance for any advice.

Dan

You may want to wait for Dave Eppstein to reply about what he mean by that.
My guess is that if you try to charge one battery with two separate solar controllers, the voltage on the battery will be confusing to the controllers (if they are actively changing the charging voltage from feedback).

I won't worry too much about it, unless I hear otherwise from anyone.... correct me if I am wrong about the following: In essence, we are doing this very often, such as have our rig plug in to shore power while under the sun. The shore power will turn on the on-board battery charger, and it will starting charging the batteries at the same time the solar controller is doing the same thing. You may end up with batteries that is not charged optimally, or you may (I doubt it) fried one of the controllers, but the possible disadvantage is not enough to make it a bad idea consider the extra energy that you are going to get with dual-controller setup.

If you are worry, you can disconnect the 50W controller to the battery, and just use your 100W setup to charge it. In an ideal system, there is only one integrated charger-converter for the rig, but it is a lot of work to change. The charger-converter take input from the solar panel(s), and 110V AC (shore power or generator), and charges the batteries. It also can do the reverse and give you 110AC if you are not plug in the shore power and disable the battery charger sub-component under the converter mode. I have not check around to see if there is such a ideal setup, but what we have is not ideal, and what you want to do is not much less optimal than what we already have.

Thank you chin_k for the response. I now understand a bit more about the charging system(s) in the Chinook. Yes, I see why the existing system is not ideal, and perhaps could have been engineered better. I think my dual charging idea will be OK, as long as the controllers, or at least one of them, phases down to trickle when batteries are full. We seldom will be on shore power...mostly boondocking, so the dual charging will be with both of the solar systems - the existing factory 50w+controller and the added 100w+controller. Almost ready to upgrade with ordering the ACOPower flexible panels and new batteries.

Thanks again for the good discussion!