Advice to make a 155w solar setup closer to 500watts

Awesome. Was thinking that after my edit. Youre probably making ice and using coolers for high traffic items. 

Thats pretty sweet when you have so much solar its not even being used!!! Im hoping to run a 375w heater this winter off the solar during the day. (might have wrote that already i forget) Once the batteries are charged its like free power just going to waste. 

Given all the inefficiencies i dont think my possible 500watts of panel will cover it. But it will supplement most i guess. 

Now that my blue charger is working that kind of changes things. I can run my genny and actually fully charge my batteries without requiring the solar. As it sits now my batteries would only get a 13.7v charge from the WFCO trailer charger. 

 
wopachop said:
Awesome. Was thinking that after my edit. Youre probably making ice and using coolers for high traffic items. 

Thats pretty sweet when you have so much solar its not even being used!!! Im hoping to run a 375w heater this winter off the solar during the day. (might have wrote that already i forget) Once the batteries are charged its like free power just going to waste. 

Given all the inefficiencies i dont think my possible 500watts of panel will cover it. But it will supplement most i guess. 

Now that my blue charger is working that kind of changes things. I can run my genny and actually fully charge my batteries without requiring the solar. As it sits now my batteries would only get a 13.7v charge from the WFCO trailer charger. 
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If you go through my post line by line, you can see where the big losses are. If you use an MPPT controller, you don't lose that 25 - 30%. If you switch to LFP batteries, you save the 20% of FLA battery loss.

This has already been too much typing. That's why I told you to call. Much faster to cover all of this. This only scratches 40% of the surface.

 
wopachop said:
Now that my blue charger is working that kind of changes things. I can run my genny and actually fully charge my batteries without requiring the solar. As it sits now my batteries would only get a 13.7v charge from the WFCO trailer charger. 
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Except for the gas expense and the noise.

 
I hear ya. I keep switching my plan. I need an inverter, so figured get a nice charging/inverter so i can have minimal genny run time to save gas. 

Then i was thinking get a 1000w inverter for now, and get more panels instead of an inverter/charger. 

Being in sunny socal its hard to ignore the solar benefits. 

Eventually will have it all. Big lithium battery bank. Big inverter/charger. Lots of solar and quality solar charger. Thats a few seasons away though. 

Third option is keep relying on propane for fridge and heat this winter. You were correct about the propane cat heater though. It produces so much water vapor. I would prefer nice dry electric heat coming free from the sun. After the initial panel cost. 

Good news for me is its more in the "want" category. I dont actually "need' more solar. Does kind of suck freezing though. Whats in between Want and Need? Um.....weed? Theres the answer folks. Get high and forget youre cold. 

 
An MPPT controller is the only way to go, they will utilize almost all of the energy from the panels with no waste. Buy a larger unit than you think you will need, I have a 60a PowMr unit and it works well. Also regarding panels, 300w+ residential panels have DC outputs over 35 volts on average, 10g or 12g wire is totally adequate for this higher voltage because there is less of a voltage drop, higher voltage = less amperage = smaller wire required. At 12v the amperage is huge so much bigger wire is necessary to keep it from melting the insulation. Your solar controller will tell you what the most efficient way to wire the panels is, there are pros and cons to both parallel and series, Fwiw my 3 x 300w panels are ran in parallel, the most I have ever seen was 852w, 55a @ 14.1v. These numbers will vary depending on how far discharged your batteries are, in other words your controller will automatically adjust the output based on your battery's state of charge. As the batteries become fully charged the controller will begin to scale down it's output.

I'm on the verge of needing a bigger MPPT controller, I have seen it shut down due to thermal loading. Also the 55a I saw one day was closer to 45a when I checked it with a Klein clamp meter. I'd like to upgrade to a 100a unit anyways. I'll sell my 60a PowMr for $50 if anyone is interested in it. 

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Was the 45amps measured down at the battery? Wonder if there is a really a 10 amp loss, or if the displayed number of 55 is just wrong. 

Its too bad this thing gets bad reviews. Found it last night. Talk about all in one answer for a decent price. Its almost too cheap. Their inverter charger without a solar controller built in cost more. Renogy Solar Inverter Charger   edit: darn it has to be a 48v battery bank

Was excited to see Victron makes one too!!! But last night looking at specs i believe its 50 hertz. Not sure if they make a version for the USA. 

https://www.victronenergy.com/inverter-charger-mppt

Why does Victron call things VoltAmps, instead of watts? 

 
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Well they are all made in China and they all likely share common components. I haven't read any reviews on it I just know it works when I use it. The difference between displayed and actual output is probably just something in the calibration, I measured the cables going to the battery right off of the unit. There is no loss, it just doesn't have the output that the display says. The values that are displayed may be mathematical calculations and not actual current measurements, I just don't know. 

Fwiw I have no issue with it other than I want a bigger unit because I want to increase my solar array in the future. I got it from LOTD a few years back, it was one of the units that he tested and found to be reliable. He was very helpful with information.

 
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What is the common larger battery bank voltage the fancy toyhaulers come with these days? 

I was hoping to buy things in steps. But that wont work if the inverter/charger is running at 24v or 48v. 

 
wopachop said:
What is the common larger battery bank voltage the fancy toyhaulers come with these days? 

I was hoping to buy things in steps. But that wont work if the inverter/charger is running at 24v or 48v. 
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They use 12v. You cannot go to 24v or 48v unless you are planning to change all of your 12v items in the trailer. Battery, inverter and dc powered items must all be the same voltage. 24v or 48v systems usually only used when you have no dc powered components like in a house. My off grid house is a 48v system but the panels and batteries only power the inverter, there are no other dc loads. 

 
I guess you could go higher voltage but would then have to convert back down to 12v for your dc items 

 
Yes im wondering if newer trailers with 120v residential fridges are coming with less and less 12v items. Water pump could be 120v. I looked up step down converters on amazon. A 48v to 12v 30A converter was only 30 bucks. 

There was one guy years ago that was smart with electronics. Larger fella. Zoning out on his name. I dont think he comes around anyone. Could have sworn 10 years ago he told me his 5th wheel was running a 48v setup. 

 
my new Moho has a residential fridge. Rest of the typical items are still 12v like lights, water pump, slide motors, etc. House batteries and inverter are 12v. 

 
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