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Discussion Starter #1
I went out and purchased another Coleman 40 W panel from Canadian Tire - $89 on Friday. Got home and the controller was Physically broken so returned it and got another package and checked that the controller was intact.

Today as it is not raining I decided to install some upgrades to the solar system. First I had to tightened the screws on the new controller as they were loose and then installed the controller into my camper.

I now have 2 - 40 W panels connected in parallel to one 7 amp controller. I also have the original 7 amp controller from my first solar panel installed in the camper.

Both controller are rated 13 V cut in and 14.2 V cut out. With the old controller, I am getting a reading of 13.8 volts at my inverter. With the new controller I am getting a reading of 15.1 volts at the inverter.

I have looked on line and there are a few comments that it seems to be a common occurance with the new Coleman controllers not cutting out until 15 V. One guy says this is fine, the controller cuts in and out and never goes above 15 volts. Mine does not seem to cut in and out and it sounds like the batteries are boiling.

Thoughts?

Should I just go out and purchase a better controller?
 

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Here is a great blog on solar if you dig around in it. This guy knows what he is talking about. I think you may need a better controller as that is the key to getting a good charge. Also the proper size cables between stuff. Too small of cables and you are really hurting your efficiency due to voltage drop.The 15v isn’t necessarily bad if the amp output is low. Bob in his blog talks a lot about charge profiles, most controllers are fixed but the cheap Chinese one I bought has software that can be used to custom configure it. I bought the cables etc to do that with my android tablet but haven’t done it. I have a tracer 20 amp with gauge which I really like. So far with my 160w single panel it charges my two 100 amp 12 v in parallel interstate deep cycle batteries really fast on the stock charging profile. I ran my RV furnace at the Swell every night and my batteries were topped off everyday usually by afternoon.

https://handybobsolar.wordpress.com

This is the controller I bought in 2016 but they may have an improved model. Bob recommends a really good controller and a good meter to monitor but I am doing fine with my set up. A volt meter and a hydrometer are tools you should have. My meter with the controller tells me all else I need to know.

EPEVER 20A MPPT Solar Charge Controller Tracer A 2210A + Remote Meter MT-50 Solar Charge With LCD Display for Solar Battery Charging https://www.amazon.com/dp/B01GMUPGX2/ref=cm_sw_r_cp_tai_dyaZAbTCYKG8T

80w of solar should do a good job if you don’t draw down your battery too far. What ever your bank is don’t go below 50% of charge for lead acid. This means if you have one 100 amp hour lead acid battery you should only draw out 50 amps. How do you tell that? By voltage. If your battery reads @ 12v that’s near 50% I think. 12.78v resting depending on temperature is full and 11.5 v is almost completely discharged. It will go less but you are ruining the battery below 11.5v
 

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My controller regularly puts out 14.6+ volts while charging. 14.2 v I think is too low. Read his blog on charge profiles he makes a case for quicker charging and complete charging using a higher charge profile. He claims most people are set up with too low of a charging voltage requiring longer charging times, etc, His claims are backed up by years of solar , off grid RV living and countless installations. Also He is an Electrical engineer so qualified to support his experience.

Maybe Coleman has upped their charge profile after new information supports doing that. The charge profiles are usually three stages sometimes four with the fourth stage being an equalizing charge for the cells. First stage is bulk, second stage is ? Can’t remember, third stage is float. You can float at a higher voltage with a low amp output.
 

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As an aside I think my system is overcharging sometimes too. It is showing 2-3 amps at near 15v output when the batteries seem to be full yet my batteries are happy and show no signs of being overcharged. 200amp bank though. This is like a trickle charge. I very rarely have to add water to the cells. Maybe leave yours hooked up for a week and monitor to see if you are losing water.

Edit: also check specific gravity for charge state.
 

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15.1 is too high. Do you have the owners manual or model number for the controller? Is it adjustable? 14.8 to 14.9 is usually enough unless you need to equalize. 13.8 will take forever to recharge a battery. 13.2 or so is float. Many RV converters only do 13.6 and often a touch less getting to the batteries. 13.6 or so will charge the batteries if you go back home and plug in and let it charge for a week or so between trips. For day after day use while boonndocking you want 14.8. I always say that there is no bad solar but 80 watts is going to give you a very limited amount of power usage. Everyone is different in their power usage so there is nothing wrong with 80 if it works for you.

Depending on how much power you use and how you camp and if you get complete daily charges you may see your battery performance taper off after a week or so. The final determining thing to keep an eye on is the specific gravity. People often go by the idiot lights on the rv monitor and never get complete charges. While this is happening you will see the specific gravity drop more and more each day until the battery falls on it's face early in the evening.
 

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Discussion Starter #6
He is recommending in his latest article not to go over 14.5 V. He did the 15 V for a while and it cooked his batteries. I will look into a new controller and just use the old one until I get a new one.
Thanks Tweaker
 

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I have 640 watts in 2 320 watt solar world panels on my toyhauler controlled by a 60 amp mppt Morningstar controller and I monitor everything with a Trimetric meter. Haven’t been plugged in since I installed system in August 2016. Read handybob that enfranz referenced. He is the solar guru. Controller charging rate is set to battery manufacturers charging specs. I have 4 6 volt Interstate batteries from Costco. Interstate recommends charging at 15.1 and that is what my controller is set at. I add water about 3 times a year. I am considering cutting controller back to 14.8 and seeing how things go. Handybob is running Crown batteries and they recently lowered recommended charging rate based on his experience.
Cable gauge and distance is extremely important. RV converters as installed by factory will never adequately re-charge your batteries. The most they will ever pump into your batteries is 13.8 volts far below any battery manufacturers specs.
 

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Looking to add a solar setup to my toyhauler (cargo trailer) that we "camp" in at swap meets three or 4 times a year. We are also thinking about using the trailer for a Haul and Ride to various places in the USA.

Currently, I have a 400wh battery bank (Goal Zero) that sits in the trailer and runs the previously mentioned router and security camera. This setup is also hooked up to the trailer brake battery and all of it gets charged when hooked up to the truck (when running). The trailer brake battery and/or the Goal Zero are enough to power the limited use of the exterior and interior led lighting and the smoker.

We sometimes carry a 7k Honda generator when the AC will need to be running, but otherwise, I think an inverter would handle the 120v load (Flourescent lights) for the brief times they are on. If I can "invert" enough juice, I can run a portable gas water heater, and I'm sure a whole bunch of crap that one "must have" when camping.

Also, and probably most importantly, I'd like to run outside cameras during the night where the trailer is stored. I have the wifi issues figured out, but would need to generate my own power to run the router and cameras.

Happy to add batteries, panels, controllers, etc.
Please assist with suggestions.
Thank you in advance,
Al

PS. I like to camp with minimal items. The "Glamping" is for my fellow motorcycle enthusiasts that think roughing it is a motel room without wifi.

There. I've rambled enough.
 

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Handy Bob is one of the first guys I ran into while researching solar. His key point is getting the voltage up to 14.8 or so. He's also big on the Trimetric so I bought one when I was still running on my Honda 3000 during our first year of Rving. I then added the Bogart engineering SC2030 solar controller which plays with the Trimetric along with 520 watts of panel and four GC2 6 volt batteries. When I went to a residential fridg I added 480 more watts of panels and paralleled another Bogart SC2030 controller and added two more GC2 batteries for a total of six. You cant have too much solar. I bought the panels at Solar Blvd in Norco Ca. and Sams club GC2 batts. I plan on going with Trojan GC2. I'm pretty hard on batteries overnight when powering a resi, 40 inch led TV, house furnace and satellite and laptops. More is better.
 

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I understand that the Grape solar controller from the Depot @ $60 is decent. Iirc it's fully programmable and may connect to a cell phone. If you upgrade controllers look for voltage setting, temperature compensation, top charging and possibly equalize. Equalizing take a good amount of panels and you need to start out with a full battery so......

They say you want to buy your last RV first and it's sort of the same with solar.
 

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first thing is to check out your battery manufacture's web site and see what the charging voltages are that they want the batteries charged at. if you don't fill the batteries up, they will die. the best way to get 2 years out of a 3 year battery is to not charge it properly. i had to study all of Handy Bob's blog for the winter before i attempted my second install, the first one with 40 watt panels failed. my second, and now my third, work great. 200 watt panels and 2- 6 volt batteries give us more power than we could ever use ( summer camping only). i chose an adjustable controller so i can set my different charge rates, to the battery manufacture's specs. i just bought 2 canadian made batteries and they want an absorption charge as high as 15.48 volts. the best advise i could possibly give is to study with Handy Bob, he knows. 69.JPG

this is a picture of my first good working system

92.JPG and a picture of my last
 

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Ej...as far as the different voltages you are experiencing from the 2 different controllers, that maybe ok. you maybe catching them at different stages of charging. a fairly good controller should have at least 3 stages of charging, float charge- maintanaince, absorption- usually in the morning to fill up from the night before, and equalization- usually once a month to desulficate.
 

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So, tinfoil, magnifying glass and some copper wires is going in the wrong direction for the whole solar charging thing for me eh? OK, I better ready the Handy Bob Solar site again. It was hard for me to read it the first time with all the negative "don't call me" disclaimers, if it's the same thing I started ready a few years back anyway.
 

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Discussion Starter #16
Ej...as far as the different voltages you are experiencing from the 2 different controllers, that maybe ok. you maybe catching them at different stages of charging. a fairly good controller should have at least 3 stages of charging, float charge- maintanaince, absorption- usually in the morning to fill up from the night before, and equalization- usually once a month to desulficate.
They are cheap controllers and I switched from one to the other a few times in a 10 minute period. The older controller never got over 13.8 V, The new one was hitting 15.1 V.
I have 2 - 6V trojan batteries that I picked up in Quartszite this winter. The last 2 - 6V batteries I had in the camper lasted 7 years and they had boiled over once from being plugged into shore power.

In the summer I found the 1 - 40W panel kept my batteries in good shape. This winter down south I did not have enough power to keep them where I wanted them.
 

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i think you may find that 80 watts worth of panels isn't going to be much better than your 40 watt, if you are going to be winter camping. you will need to do a power assement on the power you use in the worst case, and buy panels to maintain that level. it is also, all most impossible to know the shape your batteries are in if you don't have some way to monitor them. we use a trimetric, which will give you more information about your batteries, than you will ever need to know. there is a company on the island called, We Go Solar. their web site has some good info
 
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