New trailer solar build

[Jasond]

I am in the process of buying components for my solar system and shore power set up. Do I need a device to prevent the shore power from pushing juice into the solar charge controller? I was thinking of using a three way switch by Blue Sea. Off, shore power, solar power. Than an additional main battery cut off switch. Any help would be greatly appreciated.
Thank you

 

[rmaddy]

The shore power is connected to a converter (which may be separate or built into an inverter/charger combo). The converter (or inverter/charger) is then connected to the main bus bars. The charge controller is also connected to the main bus bars. It's OK to have multiple charging sources. As long as each charging source is setup to stop charging when the batteries are full, it should be fine.

It's also common to have a breaker/disconnect between the solar panels and the charge controller. That disconnect lets you work on or disable the panels when needed. You could turn off that disconnect when using shore power if you wanted.

 

[12VoltInstalls]

Do I need a device to prevent the shore power from pushing juice into the solar charge controller? I was thinking of using a three way switch by Blue Sea. Off, shore power, solar power.

Yes, there needs to be a switch to isolate 120VAC shorepower and 120VAC inverter output power. I’m not familiar with that particular blue sea item but I haven’t seen a blue sea product I didn’t like.

You don’t ‘need’ a converter unless you have big plans to run 12V accessories on shorepower. I’ve never seen a ‘converter’ I liked. It’s too simple to just have a good inverter for solar/batteries, and there’s several more efficient ways to use shorepower to charge the battery bank.

Your solar will charge the battery bank, or the tow vehicle while driving could be configured to charge the batteries. You don’t need to vehicle-charge per se- it’s just something you could do.

I admit, though, I think of shorepower or generator as an optional convenience to run AC or microwave ovens; so I’m probably weird I also like small, independent, separate components.
Other folks like plug-in simplicity which is fine. I’m just more of a boondocks-no-grid thinker for mobile living, I’m sorta anti-microwave, but I can see in some regions AC is an important consideration.

Another way to isolate shorepower and solar inverter is to wire the inverter to a 30A female RV receptacle. Then you are either plugged into 120V shorepower or plugged into the “house” 120V solar-fed batteries/inverter. They can’t mix, no a/b/0 switch or transfer switch involved. (But you’ll still need 120V breaker box)

 

[Jasond]

Ok. I was concerned the shore power would send juice INTO the solar controller. I do need (thank you) a disconnect between panel and controller.
I am planning on using this converter:

Progressive Dynamics PD9130LV 12V Lithium Ion Battery Converter/Charger - 30 Amp​

for my 12v 200AH battery. Will that work?

 

[Jasond]

Yes, there needs to be a switch to isolate 120VAC shorepower and 120VAC inverter output power. I’m not familiar with that particular blue sea item but I haven’t seen a blue sea product I didn’t like.

You don’t ‘need’ a converter unless you have big plans to run 12V accessories on shorepower. I’ve never seen a ‘converter’ I liked. It’s too simple to just have a good inverter for solar/batteries, and there’s several more efficient ways to use shorepower to charge the battery bank.

Your solar will charge the battery bank, or the tow vehicle while driving could be configured to charge the batteries. You don’t need to vehicle-charge per se- it’s just something you could do.

I admit, though, I think of shorepower or generator as an optional convenience to run AC or microwave ovens; so I’m probably weird I also like small, independent, separate components.
Other folks like plug-in simplicity which is fine. I’m just more of a boondocks-no-grid thinker for mobile living, I’m sorta anti-microwave, but I can see in some regions AC is an important consideration.

Another way to isolate shorepower and solar inverter is to wire the inverter to a 30A female RV receptacle. Then you are either plugged into 120V shorepower or plugged into the “house” 120V solar-fed batteries/inverter. They can’t mix, no a/b/0 switch or transfer switch involved. (But you’ll still need 120V breaker box)

I don’t plan, at least yet to run an inverter. Like you, I would rather boondock, but I figure we may stay at a few national parks here and there.

 

[12VoltInstalls]

do need (thank you) a disconnect between panel and controller.

You need a disconnect so that shore power and house/inverter power do not mix.
Solar charge controllers don’t need to be disconnected from the batteries even when a secondary charging source is active

what are using for devices?
All 12V? A mix of 12V and 120V? Just 120V?

it’s unclear what your intent is. I know nothing about that converter but it looks like a decent inexpensive device to power / charge a small 12V system.

Nevertheless I am not convinced you need a converter but there’s not enough information here to prove it.

With a 200Ah lifepo and (unknown; 200W?) of solar and your mention of not getting an inverter it suggests that you are using only 12V. In that case the converter makes little to no sense imho. The solar will handle it.

I love 12V stuff for smaller setups. But the reality of modern things like $150 electric fridge that runs on 60W, a $15 580W 5-cup electric coffeemaker, and fantastic 7W led lights that run on 120 make a small 1200W true sine inverter very attractive. 400W+ of panels and an inverter you can use all that without probably ever needing shorepower. Decent inverters have USB ports and there’s a bunch of milliwatt 12V LED lights out there.
I can see the attractiveness of shorepower and shorepower charging but it probably isn’t necessary.

These are my thoughts. You may not prefer these ideas- that’s fine, it’s your project.
I had an autonomously 12V functional ‘69 Westfalia I built in 2001, and set up other no-grid campers over the years. Been running 7-8mos of the year 100% solar off-grid for over three years now.

Your title, “new trailer” I assume is a utility trailer you’re rigging up. If I were doing that I’d go clean, no converter, just add some panels. With the onboard plugin from the inverter feed you *can* opt for shorepower but you won’t have to.

 

[chrisski]

Ok. I was concerned the shore power would send juice INTO the solar controller. I do need (thank you) a disconnect between panel and controller.
I am planning on using this converter:

Progressive Dynamics PD9130LV 12V Lithium Ion Battery Converter/Charger - 30 Amp​

for my 12v 200AH battery. Will that work?

Whatever your lithium battery is check the charging voltage. At 14.6 volts, this is more than I want to charge my Eve 280 ah cells I am installing. If it had an adjustable voltage that would be good, but reviews says it does not. Perhaps your battery bank has a 14.6 volts as an acceptable limit. My lithium batteries I'm installing are closer to 14 volts.

My converter charger I'm installing for my lithium upgrade matches within tolerance for charge voltage, but I will charge the batteries for a certain number of hours until the battery monitor puts it close to full and then shut the converter off. Basically, some converter chargers may not have a good float voltage for lithium battery banks. This is one Will recommended to charge lithiums:

AC Converter / Battery Charger 12/24 VDC Smart Charger 75 Amps - Listed to UL 458/CSA

Get versatility, fast charging and a warranty with the AIMS 12V and 24V AC 75-Amp Converter/Battery Charger from AIMS Power.

www.aimscorp.net

There are others that have an adjustable voltage, or a voltage closer to 14, I just chose that one.

I do believe you need a converter just for the times that the weather is cloudy and your bank is not recharging. I like to turn the heat on at night, especially in the 30s, and with the propane blower motor blowing at 9 amps, almost the whole night, my battery bank can get depleted. Won't take more than a day or two of cloudy weather to have my batteries close to 50% where I can't turn the heat on because they're to low..

 

[Jasond]

You need a disconnect so that shore power and house/inverter power do not mix.
Solar charge controllers don’t need to be disconnected from the batteries even when a secondary charging source is active

what are using for devices?
All 12V? A mix of 12V and 120V? Just 120V?

it’s unclear what your intent is. I know nothing about that converter but it looks like a decent inexpensive device to power / charge a small 12V system.

Nevertheless I am not convinced you need a converter but there’s not enough information here to prove it.

With a 200Ah lifepo and (unknown; 200W?) of solar and your mention of not getting an inverter it suggests that you are using only 12V. In that case the converter makes little to no sense imho. The solar will handle it.

I love 12V stuff for smaller setups. But the reality of modern things like $150 electric fridge that runs on 60W, a $15 580W 5-cup electric coffeemaker, and fantastic 7W led lights that run on 120 make a small 1200W true sine inverter very attractive. 400W+ of panels and an inverter you can use all that without probably ever needing shorepower. Decent inverters have USB ports and there’s a bunch of milliwatt 12V LED lights out there.
I can see the attractiveness of shorepower and shorepower charging but it probably isn’t necessary.

These are my thoughts. You may not prefer these ideas- that’s fine, it’s your project.
I had an autonomously 12V functional ‘69 Westfalia I built in 2001, and set up other no-grid campers over the years. Been running 7-8mos of the year 100% solar off-grid for over three years now.

Your title, “new trailer” I assume is a utility trailer you’re rigging up. If I were doing that I’d go clean, no converter, just add some panels. With the onboard plugin from the inverter feed you *can* opt for shorepower but you won’t have to.

Right now I’m planning on just a 12 volt system with a small inverter down the road. Loads: LED lights, usb receptacles, Iceco fridge, small diesel heater, water pump. Power: 3, 100 watt solar panels hooked up to a Victron 10/30 charger, converter/charger for shore power. Like you, I prefer 12V and staying off the grid if possible.
The shore power was for National Parks which provide shade in some states.
If you could, can you go over my schematic and give me some of your knowledge? It’s sounds like you know a heck of a lot more than me. This is the trailer I am converting for overlanding and off grid life enjoyment.

 

[Jasond]

Whatever your lithium battery is check the charging voltage. At 14.6 volts, this is more than I want to charge my Eve 280 ah cells I am installing. If it had an adjustable voltage that would be good, but reviews says it does not. Perhaps your battery bank has a 14.6 volts as an acceptable limit. My lithium batteries I'm installing are closer to 14 volts.

My converter charger I'm installing for my lithium upgrade matches within tolerance for charge voltage, but I will charge the batteries for a certain number of hours until the battery monitor puts it close to full and then shut the converter off. Basically, some converter chargers may not have a good float voltage for lithium battery banks. This is one Will recommended to charge lithiums:

AC Converter / Battery Charger 12/24 VDC Smart Charger 75 Amps - Listed to UL 458/CSA

Get versatility, fast charging and a warranty with the AIMS 12V and 24V AC 75-Amp Converter/Battery Charger from AIMS Power.

www.aimscorp.net

There are others that have an adjustable voltage, or a voltage closer to 14, I just chose that one.

I do believe you need a converter just for the times that the weather is cloudy and your bank is not recharging. I like to turn the heat on at night, especially in the 30s, and with the propane blower motor blowing at 9 amps, almost the whole night, my battery bank can get depleted. Won't take more than a day or two of cloudy weather to have my batteries close to 50% where I can't turn the heat on because they're to low..

I found this charger/converter on one of Wills lists. The price fits my current budget right now. The battery is that new one Will opened up. The Chins/Amperer/Zooms battery. Aside from the packaging, the price is right. Especially for 200AH. It’s says it can charge at 14.4v +/- .2v. I’m not sure if charging at the upper limit will be a problem. Do you have any converter/chargers in mind?

 

[rmaddy]

Looking at the schematic you just posted, I don't see the need for the 3-way switch. Just wire both the SCC and the shore power converter to the bus bars. The switch will work if you really want to ensure only 1 charge source can be active at a given moment but it's OK for the batteries to be charged from multiple sources at the same time.

The fuse you have between the switch and SCC could be replaced with a breaker which would allow you to turn it off the rare times you wish to disconnect the SCC from the system.

You should also have a proper dual-pole AC breaker between the shore power plug and the converter. Put this on the hot and line wires. It's an extra safety precaution incase your shore power connection is to a less than ideal setup.

A fuse between the converter and the bus bar (or switch if you keep it) would be a good idea too.

 

[Jasond]

Looking at the schematic you just posted, I don't see the need for the 3-way switch. Just wire both the SCC and the shore power converter to the bus bars. The switch will work if you really want to ensure only 1 charge source can be active at a given moment but it's OK for the batteries to be charged from multiple sources at the same time.

The fuse you have between the switch and SCC could be replaced with a breaker which would allow you to turn it off the rare times you wish to disconnect the SCC from the system.

You should also have a proper dual-pole AC breaker between the shore power plug and the converter. Put this on the hot and line wires. It's an extra safety precaution incase your shore power connection is to a less than ideal setup.

A fuse between the converter and the bus bar (or switch if you keep it) would be a good idea too.

The 3-way switch was more of a desire to disconnect the battery. Plus the added choice to pick just one charge source. Probably old school thought.

The shore power and plug are part of the same component. I plan cutting off the current plug and adding an outdoor receptacle for a extension cord to the campground electric. Do I still need a dual-pole AC breaker in that line?

 

[rmaddy]

I'm not sure what you are describing with your shore power and what you are planning to cut off. Nothing should be cut off. It should look something like this:

to bus bars/switch <--DC wiring--> converter <--AC wiring--> 2P AC breaker <--AC wiring--> shore power inlet in wall

and there should be a fuse on the positive wire between the converter and positive bus bar (or your 3-way switch).

You probably want a 30A shore power inlet so you can connect to standard 30A campground electric. Do an Amazon search on B07RKPZF23 for an example. Make sure your converter can handle the 30A input.

The 2P AC breaker I suggest does two things. 1) It protects your system from a bad campground electrical system. 2) It can be a disconnect from shore power without the need to go outside and unplug from shore power.

 

[Jasond]

I'm not sure what you are describing with your shore power and what you are planning to cut off. Nothing should be cut off. It should look something like this:

to bus bars/switch <--DC wiring--> converter <--AC wiring--> 2P AC breaker <--AC wiring--> shore power inlet in wall

and there should be a fuse on the positive wire between the converter and positive bus bar (or your 3-way switch).

You probably want a 30A shore power inlet so you can connect to standard 30A campground electric. Do an Amazon search on B07RKPZF23 for an example. Make sure your converter can handle the 30A input.

The 2P AC breaker I suggest does two things. 1) It protects your system from a bad campground electrical system. 2) It can be a disconnect from shore power without the need to go outside and unplug from shore power.

In the first picture I was planning on cutting off the circled plug and installing the second picture receptacle.

 

[rmaddy]

If that converter has a standard 15A plug then it may not be a good choice if you want to hook up to a 30A campground service. Check the specs on the converter. Make sure you get one that will handle 30A input.

 

[Whinny]

Sorry to hijack....
Where did you find that "second picture receptacle", been looking for one for quite a while...
I think your plugin thoughts are fine, no reason to connect to a 30a receptacle.

 

[rmaddy]

no reason to connect to a 30a receptacle.

Do campground hookups usually offer 15A connections? I'm just getting my trailer finished so I don't know what a typical campground or RV hookup typically provides. I had the impression it was only 30A and 50A but I have no idea if 15A hookups are common or not.

Where did you find that "second picture receptacle", been looking for one for quite a while...

Go to Amazon and search on "shore power inlet 15A". I see quite a few like pictured above.

In the first picture I was planning on cutting off the circled plug and installing the second picture receptacle.

I just noticed, due to Whinny's comment, that you posted a pic of a 15A shore power inlet, not 30A. If you only want a 15A shore plug then my comments about supporting 30A don't apply.

 

[Whinny]

"most" RV pedestals have 15 and 30 amp breakers and plugs, some have 50, depends on the area. I usually use a 15a cord and adapter 'cuz its lighter and easier and I'm lazy. Don't buy a 30a male to 15a female adapter though unless it has a built in breaker or fuse.

rmaddy,
Thanks for the keywords for the search-dunno why I never found them....

Edit.....brain cramp as per ususal, I was looking for a single marine style outlet..I might need a nap....

 

[rmaddy]

I have a 30A female to 15A male adapter so I can plug my trailer, which has a 30A shore power inlet, into a standard 15A outlet, like I've done at home while building the trailer. That's safe because my trailer can handle 30A but is only getting 15A when connected that way.

It seems like a bad idea to use a 30A male to 15A female adapter to let you use 30A campground service but plug into your camper's 15A inlet. But then I guess your trailer is only pulling 15A from the 30A service so I guess it's not actually an issue. But the recommendation for that adapter to have a breaker makes good sense just incase the 30A service surges into the 15A adapter.

 

[RVLiFe]

I'm not a fan of that Progressive Dynamics converter AT ALL. First, I believe it is being discontinued by the manufacturer and second, it provides a constant current and does not shut off. This will most definitely overcharge your battery in time. You can theoretically disconnect it prior to being fully charged but that means you will have to babysit it all the time.
I suggest something like this:

Amazon.com: WFCO WF-9855-LIS Deck Mount Converter/Charger with Lithium-Ion Switch - 55A: Automotive

Buy WFCO WF-9855-LIS Deck Mount Converter/Charger with Lithium-Ion Switch - 55A: Battery Chargers - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

It will charge at 14.6V for between one hour and 4 hours depending on your batteries current and voltage, then it switches to a float of 13.6V which is fine for LiFePO4 batteries. You won't have to babysit with this charger and it won't stay in a constant bulk mode like the Progressive one will. It will charge a FLA at 55 Amps and a LiFePO4 at 50 Amps.

 

[Jasond]

Do campground hookups usually offer 15A connections? I'm just getting my trailer finished so I don't know what a typical campground or RV hookup typically provides. I had the impression it was only 30A and 50A but I have no idea if 15A hookups are common or not.


Go to Amazon and search on "shore power inlet 15A". I see quite a few like pictured above.


I just noticed, due to Whinny's comment, that you posted a pic of a 15A shore power inlet, not 30A. If you only want a 15A shore plug then my comments about supporting 30A don't apply.

All the campgrounds I have been to have 15, 30 and 50 amp service.