Need Advice

[sibe]

I hope this is simple and I am just having a blonde moment..

got a simple 300 watt. 30A controlr system..

Controller has solar, battery and a load set of terminal,,, I hope to not use the load and leave my load on the batteries as it is all inplace.

I want to just add the charging for some nite use of my grou 31, 3 of them. and for winter storage..

What do I have to do if anything to hook up the controller to batteries other than a fuse, do i need to protect from the rv charger that can run on shore as the solar is on.. diodes or let it be,,

[NewBlackDak]

Originally Posted by sibe

I hope this is simple and I am just having a blonde moment..

got a simple 300 watt. 30A controlr system..

Controller has solar, battery and a load set of terminal,,, I hope to not use the load and leave my load on the batteries as it is all inplace.

I want to just add the charging for some nite use of my grou 31, 3 of them. and for winter storage..

What do I have to do if anything to hook up the controller to batteries other than a fuse, do i need to protect from the rv charger that can run on shore as the solar is on.. diodes or let it be,,

Charge controllers won’t step on each other. They’re designed to sense voltage. Any time I’m getting enough solar amperage to charge batteries, the converter sits idle. You don’t need anything connected to the load side of any controller I’ve dealt with.

[sibe]

THANKS... I was over thinking..
I am pretty good at electrical,
the guy I got system from was trying to run stuff in his house while he was away and had some bizzare hook ups.. I grabbed a punch of new left over stuff, cheap.
In fact I am going back at 6am for 2 lith 100ah batteries for $150 each.. they are partially discharged and 3 weeks old..he sold the charger he claims. I just didnt have enough cash on me.. LOL

I will have a extra 50a ATS left over and that i will sell..

[sibe]

Well he sold batteries before I got there.. it was a steal..

I got panels and cheap controller hooked up and she works fine so far.. it was cloudy , got 13.8-14.1 volts and around 4 amps.. from the 2 100 panels.. grey skys..

Lucked out with wiring, I was able to drop it down next to a roof vent pipe, right into the area where my charge/conv is located..
Just need a nice fuel / disconnect block..

I have plenty of roof room and will add 2 more panels.. this will about max out the 30A controller.. and keep the 300AH storage topped off, when stored and my max use is around 60-90AH a night when off genny and camping..

thanks for the help

[SJ-Chris]

Originally Posted by sibe

I have plenty of roof room and will add 2 more panels.. this will about max out the 30A controller.. and keep the 300AH storage topped off, when stored and my max use is around 60-90AH a night when off genny and camping..

thanks for the help

300AH bank, using 60-90AH/day, with 200w of solar will probably keep you good 90% of the time. If you have a generator as an emergency backup, all the better (just in case). Now that you've got the system in place and the wires run, adding 2 more 100w panels (if you really feel the need) on the roof (since you have space) is a very easy job and well worth it. You should be able to find some inexpensive used solar panels that match voltage with your others for $25-60 per 100w panel. With 400w on your roof, you would be good to go for as long as you camp, provided you have sunshine (...assuming your 60-90AH/day usage).



Enjoy the free power moving forward!
-Chris

[SJ-Chris]

Originally Posted by sibe

I got panels and cheap controller hooked up and she works fine so far.. it was cloudy , got 13.8-14.1 volts and around 4 amps.. from the 2 100 panels.. grey skys..

Keep in mind.....


The solar panels can OUTPUT a certain amount of amps. That doesn't mean your battery will INPUT all those amps one for one.


I'm assuming since you used the term "simple" to describe your setup, that your two 100w panels are 12v panels (which actually output at 15-19v) and that you hooked up your panels in parallel and you are using a PWM charge controller.



Each of those 100w panels probably puts out a max of ~5.5amps. So the solar panels in theory could put out 10-11amps.



Here's the thing to remember (as it pertains to typical lead acid batteries)... Depending on the charge state of your batteries (ie. 50% discharged, 10% discharged, etc) the batteries will only allow a certain amount of amps in while charging. For example, when your battery is 50% discharged you could probably charge at 75-100 amps (ie. from your alternator, or generator, or shore power, or a large enough solar system) into your 300AH bank (3 batteries). BUT, as the batteries get closer to being charged (ie. 90% charged and higher), the amount of current they allow into the batteries is significantly reduced. As an example, once my 200AH lead acid battery bank gets to about 97%, the batteries (as measured by my battery monitor) only allows in about 1-2 amps EVEN THOUGH I HAVE 500W OF SOLAR ON MY ROOF. So for practical purposes, while camping I consider 90-95% charged batteries to be about as full as I'm going to get them.


Why do I bring all this up? Well you mentioned your system delivering "4 amps". Ignoring the fact that it was cloudy, 4 amps might be the max that your batteries would accept at that time (and thus display on your controller) if your 300AH bank is near fully charged. Just wanted to let you (and anyone else who might not know) know that the state of charge of your batteries could limit the amount of charge that it looks like your solar is putting out.


Note: If you don't have a battery monitor, you should get one as they are very useful. They continually tell you the state charge of your batteries, but it is also nice to see how much power every item in your RV is drawing/etc so that you can use your batteries more efficiently. I installed an inexpensive Aili monitor (~$45) in my RVs and love it.



Enjoy the free power moving forward.
-Chris

[sibe]

Good info.. I assumed as much from reading etc..and you have confirmed....

Adding 2 more panels will be next..

Last night the batteries were at that 90ish percent.. I was out most of the day.. got home at 2ish, peak sun, Now panels are flat on roof and sun location still was pretty good, at 4pm it is actually a better angle to where RV is..
anyway....
I looked at controller.. 13.1 V .16 amps from solar.... battery shows about 95%.. only draw is propane detector..

I flipped on inverter, went to .5 amp from solor.. microwave clock and TV on standyby and antenna booster..
put microwave on 3 min high... Solar started to add 8.8-9.1.. till micro timed off.. then it dropped to 6,5,3 and hung there for a bit, After 4pm now and it is at 2.1 A from solar, Batteries show 90ish %....13.4 from solar..(bulk)

So I shall assume it is working as designed.. Adding 2 more shall do the trick.. plus it is 30A controller , I have #10 wire run , 12 feet to controller and another 2 to the system lug..

[SJ-Chris]

Originally Posted by sibe

Good info.. I assumed as much from reading etc..and you have confirmed....

Adding 2 more panels will be next..

Last night the batteries were at that 90ish percent.. I was out most of the day.. got home at 2ish, peak sun, Now panels are flat on roof and sun location still was pretty good, at 4pm it is actually a better angle to where RV is..
anyway....
I looked at controller.. 13.1 V .16 amps from solar.... battery shows about 95%.. only draw is propane detector..

I flipped on inverter, went to .5 amp from solor.. microwave clock and TV on standyby and antenna booster..
put microwave on 3 min high... Solar started to add 8.8-9.1.. till micro timed off.. then it dropped to 6,5,3 and hung there for a bit, After 4pm now and it is at 2.1 A from solar, Batteries show 90ish %....13.4 from solar..(bulk)

So I shall assume it is working as designed.. Adding 2 more shall do the trick.. plus it is 30A controller , I have #10 wire run , 12 feet to controller and another 2 to the system lug..

Sounds like it is working perfectly! Nice job. 2 more panels will just be twice the power when you need it. I really only thought I wanted/needed about 200w. When I went to build my system with some used panels, they were selling 250w panels for $35 each so I immediately bumped up my system from 200w to 500w (...and bought 500w for another RV I have even though I wasn't planning on putting solar on that one). I, like you, only use ~50-90AH/day and so far I've never worried about my batteries (which I can keep an eye on via a battery monitor) even when boondocking in partial shade.



What you also demonstrated is that during the day your solar will not only be providing max charge to your batteries (when they are up to 85-90% charged) but can also basically cover the power use of many items in the RV like your inverter (standby) and TV/etc. (...of course the microwave draw through your inverter is huge...likely 90-150amps so your batteries are really what powers that when in use).


I find solar a bit addictive/fun, but I'm capping out at 300AH of lead acid batteries and 500w of solar and a 2000w inverter. If I ever on rare occasion find myself with low batteries I've also got the generator that can charge at about 50amps when the batteries are low and need some juice (...or even the car alternator with the car idling or driving for 30 minutes to an hour).


Happy Camping!
Chris

[SJ-Chris]

Originally Posted by sibe

What do I have to do if anything to hook up the controller to batteries other than a fuse, do i need to protect from the rv charger that can run on shore as the solar is on.. diodes or let it be,,

If you haven't already, you should have a fuse/switch on not only the solar panel to the charge controller, but also from the charge controller to the batteries. I have these fuses right next to my charge controller.


https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1


This allows me to "turn off" the solar/power anytime it is needed.



REMEMBER: anytime you or someone is working on the RV and doing anything electrical you might want to disable this power source coming from the solar. They might disconnect the batteries terminals and think all is good, only to get a shock from your solar power!


-Chris

[sibe]

those are exactly what i ordered today.. lmao...

thanks , i got 4, kill negative also