Cargo Trailer Camping Converting

[sensij]

One last word on Charge Controllers. Look at a Morningstar TS-MPPT-60. They have a Voc input of 150 volts, max input of 800 watts, battery can be 12 to 48 volt battery, Surge Suppression, and fully listed with all listing agencies including UL, ETL, cETL, CE, SAE and compliant with NEC. Yes it cost more, but will allow you to save on wiring, fuses, and combiners to pay for itself. Not to mention you will sleep better at night not pushing limits.

You continue to misrepresent the capabilities of MPPT charge controllers. The Morningstar data sheet you linked says this:

*Input power can exceed Nominal Maximum Operating Power, but controller will limit and provide its rated continuous
maximum output current into batteries. This will not harm the controller (reminder: do not exceed Voc).

Emphasis mine... putting more PV on the controller and allowing the controller to run at max output will not hurt the controller. Doesn't get any clearer than that. Nominal operating power is not the same as allowable array rating.

I absolutely agree that if the S-550 batteries are used, a 40 A charge controller is undersized, and 45 A or 50 A is a better choice. The reason is *not* because there is too much array for the charge controller to handle, it is only because a better design delivers at least C/10 charge current.

[SunEagle]

60 years young.

I just hit 64 a few days ago.

[Sunking]

You continue to misrepresent the capabilities of MPPT charge controllers. The Morningstar data sheet you linked says this:

No misreptation. I know that it can be over powered to a limit. That does not mean you should. Secondly using a 100 Voc controller on the 2 panels intended is just plain ignorant limiting the user to only parallel operation and absolutely no room to grow. Why on earth would you recommend anyone doing that?

I absolutely agree that if the S-550 batteries are used, a 40 A charge controller is undersized, and 45 A or 50 A is a better choice. The reason is *not* because there is too much array for the charge controller to handle, it is only because a better design delivers at least C/10 charge current.

Duh Sensij what do you think I have been beating up weybread for? He does not understand the technology. The Morningstar TS-MPPT-60 will allow the user to configure the panels in series, listed with all agencies, will support his battery, and has room to grow. What wyebread is recommending is crippled and insufficient. What is so hard for you to understand? I know why wrebread does not understand, but you should know better.

[Wrybread]

I am not sure why you insist on calling SK that (grandpa)

to be clear, I'm calling him Grandpa Abe from the Simpsons, not just grandpa. I have nothing against grandpas! But Grandpa Abe from the Simpsons has a habit of misunderstanding what people are saying and then screaming at them. Hmm, who does that remind me of?

Speaking of which sunking, if you have different wiring recommendations, please go ahead and make them instead of just shouting incoherently. I linked to that chart because you've been using it, this is the one I usually use, which gives the same wiring recommendations per amperage by the way:

http://www.cerrowire.com/ampacity-charts

[Wrybread]

What wyebread is recommending is crippled and insufficient.

Poor sunking, so little real world experience with this stuff but still shouting about it. Anyway, parallel wiring is about 2 to 3 percent MORE efficient than wiring in series. I personally wouldn't call that "crippled".

From the manual for the Tracer 4210: image.png


Of course there's a little more loss going from the panels to the charge controller, but that's easy to keep under 3% if you use proper gauge wire, so it's basically even. And that's borne out by my tests. When I switch back and forth between parallel and series wiring when the sun is anything but at it's lowest, I get *exactly* the same watts from my panels. I'll gladly post charts for that if anyone is curious to see.

[SunEagle]

Poor sunking, so little real world experience with this stuff but still shouting about it. Anyway, parallel wiring is about 2 to 3 percent less efficient. I personally wouldn't call that "crippled".

From the manual for the Tracer 4210:

image.png

Actually using a PWM instead of a MPPT for more than 250 watts could be a loss as high as 33%.

That is pretty much based on the Amps in = Amps out for the PWM compared to the Watts in = Watts out for the MPPT.

Now if we are talking about panel wiring then it could be as low as 2 to 3 % but higher depending on the distance to run the wire for a parallel connection.

[Wrybread]

@suneagle: I'd never use pwm, using mppt of course. In an rv solar install there shouldn't be any reason to wire more than 10 or 15 feet. That's another difference between rv and house installations.

[SunEagle]

@suneagle: I'd never use pwm, using mppt of course. In an rv solar install there shouldn't be any reason to wire more than 10 or 15 feet. That's another difference between rv and house installations.

I agree the distance for the wire run should be a lot shorter in an RV then in a home. Although depending on where my panels are mounted on my 36ft RV 15 feet might be a little short to get from them to the CC.

I wish I had listened to SK and other members about an MPPT CC. I went forward and got me a cheap 30A Sunforce PWM CC and then understood the loses I would see.

On top of that I purchased low wattage panels (80W & 90W) which now required parallel wiring to get the most out of them. That then required a combination box and fuses.

To top things off I created a 12v 200Ah battery system out of 4 x 50Ah AGM batteries wired together in parallel.

3 stupid mistakes on my part (CC, battery panels & 12V AGM parallel wired batteries). All that added about $1000 to my system. What a waste of money.

I now try to explain to others that going cheap is not cost effective and while it might not be smart to purchase top of the line equipment it is better to purchase quality equipment then going the cheap way.

I do not want others to make the same mistakes I did because I thought I knew better then the experienced forum members. Now I try to get others to listen first and spend second.

[Wrybread]

I wish I had listened to SK and other members about an MPPT CC. I went forward and got me a cheap 30A Sunforce PWM CC and then understood the loses I would see.

On top of that I purchased low wattage panels (80W & 90W) which now required parallel wiring to get the most out of them. That then required a combination box and fuses.

To top things off I created a 12v 200Ah battery system out of 4 x 50Ah AGM batteries wired together in parallel.

3 stupid mistakes on my part (CC, battery panels & 12V AGM parallel wired batteries). All that added about $1000 to my system. What a waste of money.

I now try to explain to others that going cheap is not cost effective and while it might not be smart to purchase top of the line equipment it is better to purchase quality equipment then going the cheap way.

I do not want others to make the same mistakes I did because I thought I knew better then the experienced forum members. Now I try to get others to listen first and spend second.

Oof about the PWM charge controller. I wouldn't even consider using one, their 30+% loss is an absolute dealbreaker. Like most people around here I'm guessing, I've got an old PWM charge controller collecting dust (an old Morningstar Prostar 30), but it's a paperweight now since we're solidly in the era of cheap and high quality MPPT charge controllers. PWM controllers are the bad old days of RV solar. Ditto the low voltage panels.

In other words, people should ABSOLUTELY spend more to get an mppt charge controller, since there's a *massive* boost in efficiency and safety with a MPPT charge controller versus a PWM. But there's no difference in efficiency between the Morningstar MPPT-45 and the Tracer 4210, that I'm aware of at least. If someone has a link to some tests, please post!

But it's easily possible to build a spectacular solar system while still making a few cost/benefit decisions. Simply throwing money at the problem isn't always necessary.

[Sunking]

Speaking of which sunking, if you have different wiring recommendations, please go ahead and make them instead of just shouting incoherently. I linked to that chart because you've been using it, this is the one I usually use, which gives the same wiring recommendations per amperage by the way:

Like I said it is for 12 volts, 3% of 12 volts is .36 volts. Al that is required and is overkill for this application this 14 AWG and good to 25 feet. 10 and 12 AWG will work, but that is a 1-Trick Pony. Give yo a hint 36 and 72 volts.

Yes are crippling the system because you are a 1 trick pony. You are building a Trap you cannot escape from. Everything to you is 2 x 320 watt panels and a 40 amp controller. That is all you know. You locked yourself out of using panels wired in series with no room to grow. Additionally that locks you into a very specific range of battery size. Fact is most people do not need 640 watts on an RV, and some might need more. All you got is 1-size fits all.

You clearly do not understand batteries. The S-550 requires 50 amps of charge current, and if the OP follows your advice risk ruining their battery from your ignorance. One size does not fit all.

[UrbanElite]

Great 2 pages of material everyone, I'm going to ask some questions as coming off a 14-hour shift, then reading 2 pages of back and forth I'm quite confused.... :P hahaha

Let me tell you sometime about myself when it comes to projects and how I want to do this. Now in my lifetime, I've had a lot of projects and some I spent lots of money on with quality parts worked great, but might have been overkill for what I needed and didn't need. I have done projects with cheap parts and it worked great or maybe it went bad cause the parts failed then I spent the money twice and bought the right parts. So with the project, if it was for my personal house when it's used every day, I rely on the power because of the price of the system and its a house I would say just make the system and ill pay the price. But with this project, I'm looking to do it obviously safely, but affordable as well. Now I have money to spend on this as I'm putting hundreds of dollars into a solar system for a trailer.... but with a $800 charge controller, $1200 inverter with charger, $500 into panels, batteries, wiring ect... I just can not do that not because I can't afford it in some ways, but I could buy a new dirt bike or the girlfriend a new quad. SO I'm sure you can understand where I'm coming from, I want to have a good system, but I'm not going to go spend a small fortune to do it ( but I also know solar can be expensive as well) Once I build this system I'm not looking at expanding it. I can only fit these 2 360 watt panels on my roof with my new vent I am maxed out for space on the roof, so 640 watt is my limit. So let's get back to it.

That being said, I looked at the traccer controllers because on a lot of forums, videos and info sites it is a very well known and used a controller, I was hoping I was able to make it work for the price is reasonable.

So what is it going to be series or parallel?

I just need a normal inverter to power the fridge and other accessories, as I won't worry about shore power. If I'm camping I don't have shore power, if the trailer is sitting at home it's beside the house facing south which the sun light will be hitting it to charge up the system and I have Hundreds of dollars into charging systems for my racing stuff If the batteries do need a little of maintaining from that every couple weeks or so if the trailer is sitting.

Fuses: I was looking at putting a few of these resettable fuses in even if it's not totally needed just because I like the protection and you never know. I was going to mount them inside the trailer just before the controller or so https://www.amazon.ca/dp/B01EUHRSNK/...8SED749I&psc=1

Wiring: I will try to follow those diagrams. I know with it being a 16' trailer I will be keeping the wiring as short as possible. The inverter will be close the the batteries, the controller will be close to both batteries and panels.

Batteries. I brought up the S550 cause they are high AH, 6v and a decent deal around $320 a battery. Doesn't mean I'm set on them I have also looked at the s290s. But any other recommendations I would love to hear as well.

Anything else I left out or didn't think of please add into your comment with answers to my questions. Like I said before I'm very new to this, you all have been a great help and I just want a decent system for a decent price.

So from a really good site I figured out:

1200 watt-hours give or take with using 50 watts. Running withothe sun for 2 days.

5741 watt hours = Battery Bank of 479 amp hours, 390 watt in panels needed, running 2x 320 watt panels = 54 amp controller....

[Wrybread]

@sunking:

You would be over powering it and absolutely no room to grow if needed.

@sunking:

All that is required and is overkill for this application this 14 AWG and good to 25 feet

This really is hilarious, and you really aren't thinking clearly. Accusing me of not giving enough room to grow while recommending using 14 gauge wire! That saves like $10 over using proper 10 or 12 gauge wire while wasting all that time running the wires and sealing the openings to the RV, and you'd have to rewire everything to expand the system. To save $10! Honestly you're a piece of work.

And you don't realize it yet because you've never owned an RV, but with RVs 1 or 2 sizes (~300 to ~600 watts) fits the needs of almost every RV, and is in fact overkill, and is far better than almost every other rv on the road. You're vastly over complicating things because you have next to no experience with RVs. You're the cooking school graduate who can't cook a hotdog. And that's why ultimately you're always recommending that people just skip the solar part, as you continue to do in this thread.

UrbanElite:

with charger, $500 into panels, batteries, wiring ect... I just can not do that [buy the best charge controller, inverter, etc] not because I can't afford it in some ways, but I could buy a new dirt bike or the girlfriend a new quad. SO I'm sure you can understand where I'm coming from,

I sure do! Every other person with an rv thinks exactly the same way, myself included. It's all cost/benefit analysis. It's hard to imagine that's not obvious to anyone, but alas.

[sensij]

5741 watt hours = Battery Bank of 479 amp hours, 390 watt in panels needed, running 2x 320 watt panels = 54 amp controller....

Given everything you've written, if you go with the S-550's and 640 W of panels, I think you should be looking at the Victron Mppt 100/50 charge controller, $315 on Amazon. For $150 more than the 40 A Tracer might cost, that extra 10 A is assurance that you'll be able to push C/10 charge current into the batteries in good conditions. Another $75 or so gets you to the Morningstar 45 A mppt, better quality if you want to throw even more at it, although I'd struggle to spend that much for only 5 A more capability than the Tracer.

Put the panels in parallel with the simple Y combiners recommended earlier, one each for the plus and minus side. I'd use 10 AWG for the runs from the combiners to the charge controller, buy a pre-made cable twice the needed length and cut in half to get a male and female lead.

The only fusing you need is right on the battery terminal. Look at Blue Sea Systems dual terminal fuses. One of the slots would be for the charge controller, a 50 A fuse with 6 AWG if the run is short. The other slot would be for the inverter, size TBD.

[Wrybread]

Victron Mppt 100/50 charge controller, $315

Good find, I didn't realize Victron had a 50 amp model. And the Bluetooth attachment that lets you see charge status on a phone gives me charge controller envy.

[Mike90250]

600 watt Xantrex ProWatt Might start the fridge OK, if there is nothing else running and the batteries are fresh. Personally, I'd use the 1Kw inverter and not worry about the fridge starting if some other devices were on at the same time. Remember, transistors have hard limits on what they can do, unlike the dynamos at Hover Dam.