I read about MPPT vs PWM.. OK I understand..But cost wise and from what I read here on this site, is a 250watt 24V panel from solar blvd and a PWM 30 amp controller is a cheap option.$170 for panel$50 for controller.This controller accepts 48v and lowerI have two 12 volt 75 Ah batterys..Who has this set up?What amps are you generating?

Panel here...https://www.solarblvd.com/product_info.php?cPath=1_270&products_id=3027And controller... http://www.renogy-store.com/30-Amp-PWM-Charge-Controller-with-LCD-Display-p/ctrl-pwm30-lcd.htmThe contoller above is 49$ but this one looks the same and is a bit cheaper.. Whats the difference? Sun yoba solar 30...http://www.ebay.com/itm/Sun-YOBA-LCD-PWM-30A-12V-24V-Solar-Panel-Controller-Regulator-Charge-Battery-/291559410292?hash=item43e24b8a74

if you can get a Real MPPT controller and Not a Fake ....yesthe panel is a good price but you need MPPT for efficient use or its wasted moneythere are a few cheap mppt and a lot of Fake mppt, the fakes don't do the jobof converting volts to amps,

Just finished my solar install on my Toy Hauler. This might helpwww.rvbprecision.com

We have 3 X 75 Watt PV Panels on the Roof and a 4th 80 Watt Panel that We sometimes set up at Our Base Camp wherever that happens to be?The Motorhome has 4X 6 Volt Golf Cart Batteries wired to provide 12 Volts ,which supply plenty of power to the House. Most of the Lights are LED there are also some Flourescents that are seldom used so have not been converted! The 32 " Smart Television ,Blu-Ray Player,Satelite Receiver and Bose Sound System run off the Original Invertor. The Refer and Water Heater are typical 2 Way RV Units. The Genset is a 7.5 KW Onan Quiet Diesel.We have Boondocked for up to Six Weeks at a time and have never run short on Either Electricity or Propane.we seldom run the Generator when Dry Camping depending on the Solar Panels to keep Us topped up!A typical Evening Is spent watching TV , just as We do in Our Stick House! Or if We are entertaining , a Game or two of Cards . We don't particularly watch what Our Energy Usage is ,even though it is easy to monitor on the Tri Metric Display ! We have been spending Our Winters in Mexico and the South Western USA so there is no shortage of Sunshine.The Morningstar Controller is set to provide 14.8 Volts peak and will charge those Batteries to 100 % in just a few Hours.Water levels in the Batteries do require monitoring so I keep a gallon or two of Distilled Water on hand to top up from time to time.Like so many RV related subject , a little Common sense goes a long way in managing the On board Systems!

Who has Solar/ what controller/panels? | Good Sam Community

80 Replies

JiminDenver
Explorer II
Sep 14, 2015
duplicate
JiminDenver
Explorer II
Sep 14, 2015
westend wrote:

Jim in Denver is one of the more adept and experienced solar users on the Forum. You could search through his posts to see how solar is implemented correctly. (Jim, you've got my address, just send the usual check ;) ).

Thanks but I wouldn't be able to do any of it without the knowledge and experiences of people like you. I seem to learn more from the I have this, and do this in this conditions than all of the formulas and theories combined.
JiminDenver
Explorer II
Sep 14, 2015
lawrosa wrote:

Just looked up the eco worthy. Looks pretty good and only $99 bucks..

I have to look at specs but I would assume again that it would be best to couple it with a 24 volt panel.

What I read is the mppt controller would double the amps of the 24 volt panel? So that 8.7 amps that 240 panel produces would be around 16-17 amps.

Maybe I would put on the roof of the RV, but I wonder the performance when in the shade....

Probably my load per hour is about 5 amps. TV and a fan. Water pumps use, ect.

I was thinking of doing an invertor to the RV panel somehow.

Its probably wrong to backfeed the panel, and have the main breaker off... huh?

http://www.amazon.com/ECO-WORTHY-Charge-Controller-Regulator-15-30/dp/B00FF1KGT4

A 240w panel should easily do 16a while tracking. The Eco-W can do a 24v panel or a pair of 12v panels in series up to 275w. Pay attention to the specs of the panel and the limits of the controller.

For the hassle a portable allows you to park in the shade and collect more than if the panel was mounted. Solar in the shade isn't such a good idea.

I plug my shore cord into the inverter. the converter is never on but the rest of the outlets are live.

There are a few of us that have used the 24v panel/Eco-W as portables and mounted. I may have used it longer but for day to day experience BFL has much more than I do. I also think he does more with the combo than I did when I ran a single panel system as in use a inverter.

What that 230w panel, 25 ft of cords and Eco-worthy did do for us was produce more power than we could use. Even though it could produce 15a or more tracking the sun, the system was in float most of the time because we don't use enough power over night to pull down the battery much. We could turn on all the lights, fans and even the furnace the system would cover it so the battery stayed in float all day. I've taken the concept of running stuff directly off of the system that the one I use now will run a small air conditioner or cook on a electric cooktop.

Portables, especially big ones have downsides too. Not only do you have to store it for transport but you have to pull it out to use the rig if you just stop for the night. You get no charging while on the road or if the trailer is stored and of course anything not nailed down can grow legs and walk away.
lawrosa
Explorer
Sep 13, 2015
westend wrote:
lawrosa wrote:
Yes, you don't want to just have a hack job from inverter to load center. It usually isn't necessary because you can either plug your shore cord into the inverter or install a transfer switch.

Yes but if you do that then wouldnt the inverter try to charge the batterys through the RV convertor?

You would have to turn off the charging part on the rv convertor. How would you do that?
I have my converter connected by itself to one 120 V AC breaker.

OK I can connect an invertor to an empty 15 amp breaker in my panel.

So thats back feeding the panel. I would then need to flip off the main for saftey sake incase someone decided to plug the rv in to shore poer. I assume bad things will happen.

The breaker could be that switch. If you have a conventional load center/12 V distribution panel, the best way would be to interrupt the AC power to the charging part of the system with a panel mount switch on the front of the panel.

Where would you interupt this power? That would be if I plug the RV into the invertor.

I have the 6332 here with the option Q board. 12 amp max charging I believe

http://www.hayseed.net/~jpk5lad/RV%20Information/MagnaTek%20Pwr%20Converter/RV%20Binder1.pdf

Two wires need to be attached to the switch and if you have enough slack in the positive phase of the AC wiring, cut, strip, and attach. An alternative is to mount a receptacle/box and attach a male plug onto the converter wiring, the converter being connected to the receptacle when in use.

I understand the receptical box with plug but thats backfeeding too. I assume you have to make sure you unplug when attached to shore power..

At present, I power a 120 V fridge and entertainment gear with an inverter. The fridge is plugged directly into the inverter and the entertainment gear is powered by a separate circuit with it's own, Hubbell receptacle. I move plugs when connected to shore power.

Id rather power the whole panel but have not found a way online to do this without

1. having the invertor charge the batterys through the converter ubless you can disconnect the charging circuit.
2. Backfeed the panel but need to turn the main breaker off. Thats not really idiot proof.

Im looking for a simple method.
westend
Explorer
Sep 13, 2015
lawrosa wrote:
Yes, you don't want to just have a hack job from inverter to load center. It usually isn't necessary because you can either plug your shore cord into the inverter or install a transfer switch.

Yes but if you do that then wouldnt the inverter try to charge the batterys through the RV convertor?

You would have to turn off the charging part on the rv convertor. How would you do that?
I have my converter connected by itself to one 120 V AC breaker. The breaker could be that switch. If you have a conventional load center/12 V distribution panel, the best way would be to interrupt the AC power to the charging part of the system with a panel mount switch on the front of the panel. Two wires need to be attached to the switch and if you have enough slack in the positive phase of the AC wiring, cut, strip, and attach. An alternative is to mount a receptacle/box and attach a male plug onto the converter wiring, the converter being connected to the receptacle when in use.

At present, I power a 120 V fridge and entertainment gear with an inverter. The fridge is plugged directly into the inverter and the entertainment gear is powered by a separate circuit with it's own, Hubbell receptacle. I move plugs when connected to shore power.
full_mosey
Explorer
Sep 13, 2015
A 24V 250W panel run through a 12V PWM controller will produce about like a 12V 125W panel. Don't do that! :) You lose 50% of available power.

HTH;
John
pianotuna
Nomad III
Sep 13, 2015
Whole house solutions for small solar require the ability to disconnect the converter, switch the fridge to gas, and the water heater to gas. This can be done manually, or using a sub panel with a transfer switch. I chose manual, because that leaves me in control of what will run.

I sometimes deliberately run the water heater on 120 volt via the inverter so that my solar harvest is not wasted.

Large solar (1600 watts) still requires disconnecting the converter.
EsoxLucius
Explorer
Sep 13, 2015
Wow! You can lead a horse to water but you can't make it drink.
time2roll
Nomad
Sep 13, 2015
lawrosa wrote:
So that is the max amps I would be able to get from the panel in full sunlight? 8.4 or so ISC?
Yes the PWM controller cannot produce more amps than the panel.
PWM just clips voltage to what the battery needs for charging.
lawrosa
Explorer
Sep 13, 2015
Yes, you don't want to just have a hack job from inverter to load center. It usually isn't necessary because you can either plug your shore cord into the inverter or install a transfer switch.

Yes but if you do that then wouldnt the inverter try to charge the batterys through the RV convertor?

You would have to turn off the charging part on the rv convertor. How would you do that?

Forum Discussion

Who has Solar/ what controller/panels?

80 Replies

About DIY Maintenance

Related Content

Solar panels/controller advice

MPPT solar charge controller with 12v panels...

Solar Panel Controller Advise

Solar-Panel to Controller Loss

Recommended Solar control module for 50W solar panel?