12v Solar,.Generator, inverter setup

[J.P.M.]

I think so, it's a good education for anyone willing to follow along and do the math for themselves. Even if the OP is a lost cause, others might learn from his mistakes.

I suppose, but the OP appears to need more help than he can get here and IMO only, in areas that do not appear to be forum material related.

[Sunking]

Monroe here are some facts and why you are catching so much grief. Everyone that has replied to you are real engineers. Three of them are Moderators. You claim to be an electronic engineer, but it is crystal clear you are not, and that makes you a liar. You do not even know the basic fundamentals. Some examples:

I can not run any panels in series on the RV

Complete BS. wiring in series is easier, takes 1/5 the wire and much smaller wire required. Even a DIY Joe Blow knows this. By using PWM forced you to wire in parallel robbing you blind with wire and inefficiency.

I will produce the math because other people may benefit from the comparison.

Yeah you made that threat and never did it. I took care of that for you and showed you the math and made you look ignorant. The absolute best efficiency a PWM controller can achieve is 66%, MPPT is greater than 95%. No contest. Problem is you do not understand the math and is a basic fundamental any first year engineering student would understand. If not would fail class and forced drop out.

#5 There is a problem charging from multiple controllers and multiple sources if you don't see that then well.

More BS. It is a common practice. As long as you have the voltage set points the same in both controllers will work just fine. The only issue you wil have, a non issue, is late in the Absord phase when the batteries are charged up one controller might drop out which is a non issue because the batteries are charge. If that bothers you, they make controllers so one can be set up as Master, and the other as slave. Those would be MPPT controllers, and if you would do things correctly would only need 1 controller.

If you plug the inverter into the shore power connector you sure as hell will get a charging loop going even if you have an ATS

This proves you are no engineer and a liar. Even a DIY RV'r knows if you plug a RV Inverter with an ATS into Shore Power or Generator, all power comes from the commercial AC Power or Generator. That is what the ATS does you moron.

So take the advice of the Moderators and myself. Take your biz elsewhere. You have been given good advice.

[Monroelkjr]

Why would I buy a MPPT controller when I already have a $300 PWM controller the wire and everything I need to install the panels? Especially when this system just supplements my generator?

Why can you not accept that is false economy from my point of view?

I will produce the math that shows what the cost difference is FOR ME and the difference over time. When I feel like finishing it because I will do a very thorough report.

As for problems charging from multiple controllers here is some evidence to that point.

http://www.cruisersforum.com/forums/f14/multiple-charging-sources-to-the-same-battery-bank-30085.html

https://roadslesstraveled.us/charging-rv-marine-batteries-solar-power-shore-power/#alternator

The boat guys seem to care more about this than the RV guys do. I know you can set voltages and get results you want but sometimes that's pretty fiddily.

So there is room for improvement over just an MPPT controller and I don't want to buy one right now for the RV because something better is surely soon to arrive that solves all the issues I care about.

I also feel it would be bad economy to buy an MPPT controller and not use 24v!

Another issue is the alternator on the RV will only charge to 13.7v so there are some solutions from Sterling Electric and a few others that provide multi stage charging from an alternator or DC to DC from the batteries.

I can just install some diodes in the sense line and raise that to 14.4 but then there would be no multi stage charging it would help but not solve the issues there.

So because I have the PWM and I want something that is really not available yet WHY NOT KEEP the PWM and just move on for now?

As for your insults BAAaaaa HAAaaaaa Whatevs man.

You can't make me go buy a MPPT controlier because I don't need one dude.

I simply told you guys that and we should have moved on!

But it's obvious a system I paid nothing for will beat any system I had to pay for for quite a few years. That math is easy right!

Your a blustery bunch aren't you? Can't have it your way so your going to kick things around.

You can not win here because I paid nothing for that system and that's totally false economy to change it.

So I won't win in the math there? Your just plan wrong about that.

[jflorey2]

I'm not going to buy a MPPT controller I have a PWM controller and it makes no sense for me to go buy one for the RV.

If you are OK with the inefficiencies of the PWM controller and the additional cost of the wire, then by all means, keep your PWM controller. Won't work well, but it's your decision.

But if you are just going to do whatever you want anyway - why bother posting?

I never parked in the shade expecting solar power where did you get that?

If it's so hot you will consider running an A/C it is wise to park in the shade. (common sense.) At that point roof mounted panels are going to be shaded. Hence the value in having panels that can be mounted remotely.

[Sunking]

But if you are just going to do whatever you want anyway - why bother posting?

Exactly. He came here to ask for help. He received good advice and rejects it.

FWIW Monroe that now makes 5 engineers all saying basically the same thing. We are not the ones not listening to what you want to do. You refuse to accept the answers. We cannot change Chit to Shinola if you refuse to make upgrades and changes. It certainly does not help with you pretending something you clearly are not.

[Monroelkjr]

Tell me what sense it makes for me to go out and buy a MPPT controller when I already have the wire the panels and everything I need to do it that way and it cost me nothing?

You don't see the bad economy in that?

You can call me a liar not only do I have a degree in EE I was a GSE in the navy.

The efficiency of the panels does not make sense to throw it out!

I have NEVER parked in the shade. That's just plan stupid to say I would. But I could with the trailer as remote.

I will provide the math and I'm not going to just throw out there some numbers. I'm going to make a full report and let people decide for themselves.

I will take actual data to support what I'm saying it may take a month to finish it.

I will use the MPPT controller on the RV to test it out before I put it on the trailer and show the exact differences.

The cost difference of which I will present also.

It's just plan stupid to keep this up! Let me make my report.

Once I said I needed to keep the PWM that should have been the end of it and we moved on to other things that might be done.

But no you got your panties in a wad because I said something you didn't like.

Lol just hold on I'll get the data and prove my point.

Monroe

[jflorey2]

Tell me what sense it makes for me to go out and buy a MPPT controller when I already have the wire the panels and everything I need to do it that way and it cost me nothing?

Because you will get more power out of the same panels. And when you have to reconfigure the panels you will need less wire to do it.

The efficiency of the panels does not make sense to throw it out!

That's what we have been saying. It makes no sense to throw out 30% of the output of your panels. That represents energy you have lost.

I have NEVER parked in the shade. That's just plan stupid to say I would. But I could with the trailer as remote.

Right - that's what we have been saying. Mounting the panels separately makes that possible.

I'd be surprised if you never parked in the shade and will never want to. It makes a 30F difference in the interior of your van. If you travel in the summer it will make a huge difference.

[Sunking]

Monroe 5 engineers are all telling you the exact same thing. Get a clue.

No one ever said throw the panels out. Using your PWM controller throws away 30% of the power from the panels. .

[Monroelkjr]

Right and all I said was it will take 5 years to make up the cost difference for me to go MPPT on the 800w system. 30% is a worst case scenario also and you wont be losing 30% all the time.

So I am going to collect the data and present the difference.

In 5 years I'm sure something new will come out that I want instead anyway. Something that will better control the 4 sources of DC in my RV.

This is a practical study and I will post the results here.

Someone who does not have a controller yet should obviously buy an MPPT controller of course! But lest see how long it takes in real world numbers to pay for it's self eh?

Monroe

[Sunking]

This is a practical study and I will post the results here.

Don't bother, you do not even know how to use what you have already.

PWM Output Current = Input Current..... End of story.

You have 5 panels with Imp = 7.1 amps = 35.5 amps
4 panels with 3.1 amps = 12.4 amps
Total Current = 48 amps max into a 12 volt battery = 576 watts from 825 watts of panels.

You do not have enough common sense to use 1 controller you already have. Your 60 amp PWM controller will handle everything you have now and more. Instead you use 2 controllers. and then complain it causes you problems charging. As a bonus to your ignorance of facts you loose 250 watts of power. No one cares nor is anyone going to help a fool because you refuse to make any changes. So get lost. You are wasting our time.

Well almost wasting our time. Some of us are