Community Forums

azSkier · 06-24-2019, 09:08 PM

My coach has a 5w or 10W solar panel directly connected to the chassis batteries. It is useless at 14 years old and does not charge my house batteries.

So, I have minimally upgraded the system.

I removed the old panel and installed a 100W renology flex panel. I also installed a 10A Renology wanderer (PWM) solar controller. These new components use most of the existing wiring, but I did add new wires to connect the controller to my generator with 12ga wiring and some fuses. The max Amps for this setup is 5.5A.

I know It is overkill for charging my chassis batteries, but I also want to charge my 8 house batteries when I am in outdoor storage.

So, I have added a small wire with plugs between the positive terminal of the chassis battery to the positive terminal of the house battery. I have quick connects that allow me to easily connect the 2 battery banks when I leave my coach in outdoor storage and disconnect when I am using my coach.

I added a 10A fuse as part of this wiring. I wouldn't want to start my coach and run a large current through my small wire. This way, if I should forget to disconnect before starting the coach, the fuse will fail and separate the 2 battery banks.

This implementation is working, but would appreciate any thoughts or warnings.

PS. My coach has a BIRD. My interconnect may not be necessary. I am still researching this.
Thanks

Unplanned Tourist · 06-24-2019, 09:36 PM

It could be that your relay for the BIRD system is bad. The contacts inside the relay can carbon up and the relay stops working.
Happy Glamping.

twinboat · 06-24-2019, 11:19 PM

If you are solar charging the chassis batteries, the key may need to be on for the BIRD system to work, allowing house battery charging.

If you set it up to solar charge the house battery, then the BIRD will allow chassis charging.

azSkier · 06-25-2019, 07:40 AM

With my existing BIRD being 14 years old, I have been carrying a spare. I need to verify voltages. The bird should connect the 2 banks when either side gets above 13.1V.

I also need to verify that the BIRD is always on. When I store my coach, I turn off the house 12V system to reduce parasitic draws. Not sure whether the bird is before or after that switch.

The chassis batteries will need to be nearly fully charged before the voltage will get that high.

Thanks

azSkier · 06-25-2019, 07:50 AM

That's my issue. The Bird is after the battery disconnect. So, the chassis battery is always isolated from the house battery when the coach is stored.

That is why I need a manual connect/disconnect setup.

John Hilley · 06-27-2019, 09:27 AM

A Trik-L-Start will solve your problem

azSkier · 07-07-2019, 12:51 PM

Here is my project update.

Solar Battery Trickle Charger for long term coach storage.

My coach has 10 AGM batteries; 2 chassis batteries and 8 house batteries.

The chassis batteries have a parasitic draw of .3A while the house batteries have a parasitic draw of .5A

I store my coach outdoors and upto 5 months during the winter. I want a solar charger to keep the batteries charged during these periods of long term storage.

I purchased the following;
Renology 100W flex solar panel
Renology 10A adventurer solar controller
3 inline blade fuse holders
various lengths of 10Ga and 12G wire.
Heavy duty velcro
Heavy duty gorilla tape.

My coach had a 5W solar panel connected directly to the chassis batteries. This panel was removed and discarded.

My plan evolved as I worked my problem. Here is how the final configuration ended up.

I mounted the flex panel on the roof using heavy duty velcro. I then used the gorilla tape to seal the edges and firmly fix the panel to my roof.

I used 10GA Renology cables to connect to the panel and to the original solar panel wires. The original wiring is 16Ga wire and can handle the 5.5 Amps provided by the Renology panel.

The original wires run to the dash of my coach and connected to a solar light indicator. I removed the indicator and connected the Renology Adventurer solar controller to this wiring.

I need to connect the solar controller to my batteries, so I ran 12GA wires from the solar controller mounted on the dash through the firewall and into the back of my generator. This gives my a
good low impedance connection to my chassis batteries.

Each end of these new 12Ga cables have blade fuses attached. The fuse holder nearest the generator has a 15Amp fuse, while the holder nearest the solar controller has a 10A fuse.

I now have a good trickle charger for my chassis batteries, but I need to charge my house batteries.

So, connected a wire between the 2 battery systems. I have a quick disconnect so I can easily disconnect the 2 battery systems. I also installed an inline fuse holder and keep a 10A fuse is this holder.

My intent is to disconnect this wire before starting my coach. If I forget, high current will flow though this wire and blow the fuse. I have done this a few times already.

Anyway, I think this is a worthwhile effort since my coach experiences periods of medium and long term storage.

Davidmill · 07-08-2019, 12:44 PM

That is amazing!!!!

I wonder if that Would that charge my sons electric bike that he folds up and brings with us up north. This is the one he got incase you need to see the amps or watts or what ever... I have no idea about solar panels but I bet you learn quick.... He has the 1000 watt motor https://Motorcityebikes.com if it matters...

Ray,IN · 07-09-2019, 06:31 PM

Without increasing wire size from the 10w panel to the battery bank, will you realize the full potential of the 100w panel?

azSkier · 07-10-2019, 07:12 AM

Quote:

Originally Posted by Ray,IN

Without increasing wire size from the 10w panel to the battery bank, will you realize the full potential of the 100w panel?

I did investigate this issue.

18ga wire can handle 7A while 16ga wire can handle 10A. This 100W solar panel has a max current of 5.5A.

The existing wiring that I am using is 16ga, so I feel confident the setup will work fine.

Pappion · 10-13-2019, 05:59 PM

Smart maintainers will stop charging until the battery voltage drops.

Many of the cheap controllers are not safe for maintaining. Every morning they try to charge the battery. Even Float levels are too high for extended periods on a fully charged battery.

My old 10W was not doing the job for my 2 AGM size 30. Tried a 20W, wow total over kill. Tried a new 10W, still over kill, once the batteries are fully charged. So I tuck it out of sight, it just gets reflected sun from the diamond plate on the TT front.

BTW: I added reverse voltage blocking diodes to my wiring. Since the 2 new panels did not advertise for direct battery connection.

azSkier · 12-15-2019, 06:22 PM

Here is an update. The solar battery maintainer (100W panel) worked great during the summer and fall seasons. The setup could maintain the 10 AGM batteries and keep up with the various parasitic draws.

Not so much in the late fall and early winter. Just before Thanksgiving, I had to disconnect the 8 house batteries. The solar system could not keep up. Just not enough daylight.

So, I disconnected the house batteries and only have the 2 chassis batteries connected to the solar charging system. Well, since Thanksgiving, we have had cloudy, stormy weather and nearly constant clouds. Pretty typical. After 4 weeks, the chassis batteries had discharged more that I had hoped (much more). Just not enough sunshine.

So, I have disconnected the chassis batteries from everything and will leave it this way until March.