Any diy RV solar experts here?

[Jonas Grumby]

I have a Motorhome with the usual inverter/charger that charges the lead acid battery when plugged into shore power. Also the engine alternator will charge the house battery. I want to add a 200w solar panel on the roof. Install a mppt solar controller and connect to house lead acid battery.
#1 Will this back feed into the house inverter/charger or engine alternator and cause problems?
#2 when plugged into shore power or house generator running, will the 12v from the house charger back feed the mppt and hurt it?
#3 will engine alternator hurt the mppt?

I have herd both, “no problem” or, I have to install a disconnect on the mppt when charging with any other source.

 

[rivermobster]

Depends where and how you hook it up, for the most part...

I have my charge controler output hooked up the the 12v cut off switch.

Once I turn the switch off, it's Only connected to the batteries. Works as a trickle charger. Just don't forget to check the water level in the batteries regularly!

 

[Jonas Grumby]

Depends where and how you hook it up, for the most part...

I have my charge controler output hooked up the the 12v cut off switch.

Once I turn the switch off, it's Only connected to the batteries. Works as a trickle charger. Just don't forget to check the water level in the batteries regularly!

So you are saying, mppt will back feed house inverter and vicversa? how Come the alternator and house inverter get along?

 

[rivermobster]

So you are saying, mppt will back feed house inverter and vicversa? how Come the alternator and house inverter get along?

I'm not saying that at all.

I'm just telling you how I hooked mine up. I have no issues with it.

 

[Ricks raft]

I have been looking at doing this as well. So far multiple places have said no problem, just hook directly to batteries. Which really makes sense since the batteries already have 6 or 12v power without chargers and don’t “back feed“. And all forms of chargers don’t over charge the batteries…

 

[rivermobster]

I have been looking at doing this as well. So far multiple places have said no problem, just hook directly to batteries. Which really makes sense since the batteries already have 6 or 12v power without chargers and don’t “back feed“. And all forms of chargers don’t over charge the batteries…

I can tell you my old one Absolutely overcharged the batteries. Dried em out completely.

I just replaced it with a brand new fancy Bluetooth job. I haven't had it long enough to know.

 

[Jonas Grumby]

I can tell you my old one Absolutely overcharged the batteries. Dried em out completely.

I just replaced it with a brand new fancy Bluetooth job. I haven't had it long enough to know.

Ya these newer victron mppt controllers you can set cut out voltage and a host of other things. I just didn’t want to blow up new or old equipment, or cause a fire.

 

[Icky]

Following as I need to upgrade my toyhauler

 

[adam909]

Theres a guy on river daves other site glamis dunes.com that all he does is solar on RV's

 

[wash11]

@The Chicken your guidance is appreciated here when you get home.

 

[Mikes56]

I put one 100w Solar panel on the roof of my motor home and ran the wire down the roof refrigerator vent, to the red and black 10 gauge wires on the back of the fridge. It worked great for years until I sold the motor home.

 

[boatpi]

I know expert on motorhomes, but we do some small solar stuff and it’s all about the solar controller that controls backfeed and won’t allow the batteries to be overcharged

In our looper system, we use an inexpensive solar controller. You can get on eBay or Amazon. It has a Blueface to it. It’ll take several hundred watts of solar power off of bottom number 18 wire and then use that as a trickle charger into your battery. they’re under $20. They even have a digital display.

 

[mesquito_creek]

I have been looking at doing this as well. So far multiple places have said no problem, just hook directly to batteries. Which really makes sense since the batteries already have 6 or 12v power without chargers and don’t “back feed“. And all forms of chargers don’t over charge the batteries…

This ^^^ “just hook directly to batteries” through the mppt charge controller.

 

[boatpi]

You need this to regulate the charging or the solar cell can overcharge the battery. Cheap, but they do work. https://www.ebay.com/itm/1956603189...dWobhAUeQ==|tkp:BFBMlvuan9Bk&var=495531032255

 

[trophybug19]

I have a Motorhome with the usual inverter/charger that charges the lead acid battery when plugged into shore power. Also the engine alternator will charge the house battery. I want to add a 200w solar panel on the roof. Install a mppt solar controller and connect to house lead acid battery.
#1 Will this back feed into the house inverter/charger or engine alternator and cause problems?
#2 when plugged into shore power or house generator running, will the 12v from the house charger back feed the mppt and hurt it?
#3 will engine alternator hurt the mppt?

I have herd both, “no problem” or, I have to install a disconnect on the mppt when charging with any other source.

What motorhome do you have? In my bounder I added a renogy kit. Simple install and the mppt controller regulates everything. Had no issues, it also kept my chassis battery charged too. I can go more in depth if you want. But the 200 watt renogy is a good easy system. I did upgrade my mppt to the 40amp incase I wanted to add more solar.

I'm now switching house batteries to lithium which I will say if you plan on doing ever now is the time to buy the right parts. I'm about to do an update on my thread of switching over to lithium in the rv section.

 

[rivermobster]

I put one 100w Solar panel on the roof of my motor home and ran the wire down the roof refrigerator vent, to the red and black 10 gauge wires on the back of the fridge. It worked great for years until I sold the motor home.

Pretty close to how I did mine. The electrical box was close to the fridge, that's why I ran it to the switch in there.

It's a direct route to the batteries. No need to add additional wires.

 

[Jonas Grumby]

What motorhome do you have? In my bounder I added a renogy kit. Simple install and the mppt controller regulates everything. Had no issues, it also kept my chassis battery charged too. I can go more in depth if you want. But the 200 watt renogy is a good easy system. I did upgrade my mppt to the 40amp incase I wanted to add more solar.

I'm now switching house batteries to lithium which I will say if you plan on doing ever now is the time to buy the right parts. I'm about to do an update on my thread of switching over to lithium in the rv section.

2018 Entegra.

 

[Jonas Grumby]

What motorhome do you have? In my bounder I added a renogy kit. Simple install and the mppt controller regulates everything. Had no issues, it also kept my chassis battery charged too. I can go more in depth if you want. But the 200 watt renogy is a good easy system. I did upgrade my mppt to the 40amp incase I wanted to add more solar.

I'm now switching house batteries to lithium which I will say if you plan on doing ever now is the time to buy the right parts. I'm about to do an update on my thread of switching over to lithium in the rv section.

Thanks for your input, but a couple of questions. I have looked at the renolgy site, they have many kits, but don’t really show existing setup. Did your kit consist of panels and MPPT? When you say the MPPT, took care of everything” did you just connect panels to one side of MPPT, and house battery to the other? Leaving house shore power charger and chassis alternator connected to house battery also?.
I do plan on lipo down the line so will get a MPPT that in voltage adjustable.
THX.

 

[trophybug19]

Thanks for your input, but a couple of questions. I have looked at the renolgy site, they have many kits, but don’t really show existing setup. Did your kit consist of panels and MPPT? When you say the MPPT, took care of everything” did you just connect panels to one side of MPPT, and house battery to the other? Leaving house shore power charger and chassis alternator connected to house battery also?.
I do plan on lipo down the line so will get a MPPT that in voltage adjustable.
THX.

New 200 Watt 12 Volt Solar Premium Kit

This kit comes with two 100W Polycrystalline Solar Panels totaling 200 Watt, one 20 Amp MPPT Charge Controller, 20ft MC4 Extension Cables, and two sets of Z brackets for Mounting. Free Shipping! On Sale!

www.renogy.com

This is the kit I bought but I upgraded to the 40amp mppt.
For install I mounted solar panels ran lines to controller. I added a breaker so I had a way to disconnect panels from mppt. Then connected wires from mppt to batteries. Pretty much that's it.
When solar is going since house and chassis go through the BCC the solar keeps both charged.
And never had any issues when connected to shore or when generator is running. The mppt protects itself.
If you plan on going lithium later get a mppt with dc to dc charging incorporated in it.

DCC50S 12V 50A DC-DC On-Board Battery Charger with MPPT

Introducing the RBC50D1S, harnessing MPPT solar charging and starter battery charging to provide rapid replenishment for house batteries. Equipped with multiple electronic protection mechanisms, it ensures optimal energy utilization without compromising the vehicle's starter battery.

www.renogy.com

I'm currently looking at this one.

 

[Ricks raft]

What motorhome do you have? In my bounder I added a renogy kit. Simple install and the mppt controller regulates everything. Had no issues, it also kept my chassis battery charged too. I can go more in depth if you want. But the 200 watt renogy is a good easy system. I did upgrade my mppt to the 40amp incase I wanted to add more solar.

I'm now switching house batteries to lithium which I will say if you plan on doing ever now is the time to buy the right parts. I'm about to do an update on my thread of switching over to lithium in the rv section.

I’ve used the Renogy 100w kit on a couple remote network ptp bridge/access point/camera set ups and gate keypad/cameras. Probably over kill, but they were easy and have been working for a few years now.