Help me pick a charge controller for my solar install (1 Viewer)

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I would appreciate your suggestions on this next move....

So, i am seriously considering picking up another 60W panel, purchasing these connectors: http://www.solarblvd.com/Cables-&-W...PV-AZS4-2P-MALE-(-),-1P-FEM/product_info.html

Then i can run two panels in parallel which should give me plenty of power for my needs. Plus, the size of them will keep it fairly easy to store both of them in the cruiser while on trips without taking up large amounts of room.

My main questions are, first, has anyone used these to run two panels in parallel? Second, would it be wise to keep both panels the same wattage? For example, could i purchase a 100W panel, and keep my 60W panel, run them in parallel and in essence have 160W capability?
 
As far as storage goes it is indeed not a bad idea to have 2 smaller one vs 1 larger one, I think.

You can wire panels of different power ratings in parallel but ideally you would want the nominal voltages to be the same or close. And you want diodes in the circuits (maybe built in the panel wiring already). And of course your charge controller and wires should be able to handle the total current.

Those connectors look like standard MC4 couplings. If that's what you have already on your panel, it should be just plug and play. But you can use any connector or just solder wires too. Nothing magical about those connectors, just easily disconnected and weatherproof in principle.

Do note, though, that the controller in the first post looks like a 10A one, so you'd be pushing it with 160W.
 
e9999 thanks for the reply! Good catch on the 10A capacity, i didn't think about that.

You are correct, i currently am using the MC4 couplings, so those adapters would be simple plug and play.

I have a great spot just beside the fridge where my single 60W panel slides in beside the fridge with extra space so it wiggles. I think two of them would fit snug.
 
If you end up with 2 of the same panel, then you can drill a few holes in the frames and put a hinge to make them a folding 'panel'. Few more bits of angle iron or aluminium and you have legs. You've basically made what they sell as a 120W folding solar panel in oz. Then you can run some wires from one to the other to parallel them and it's all neat and tidy as a single 'unit'.

My 80W folding panel in oz:

metzke2.jpg


cheers,
george.
 
you may want to read a bit about mix and match of panels. I don't think that anything will go dramatically wrong -as in going up in flames- if they are significantly different voltages (e.g. Vmp) but things can get unbalanced, inefficient and running at the lowest common denominator, so not great, from what I read. Although I remember reading vastly different explanations and prognostics, so I'm not exactly sure what would happen, the miracle of the Interweb for ya. Maybe George knows.
Regardless, you are surely safe if the 2 panels are the same. That would make it 120W, IIRC, so OK with your controller. And that should be plenty for your fridge and some toys in most situations.
Personally, I would rather have the panel stored if not mounted on the roof somewhere than stored inside, though, the latter is bound to be a pain sooner or later I'd think.
 
Parallel of 2 similar/same panels would be no problem. Panels are themselves made as series/parallel strings of cells.

I've always transported my solar panels within the vehicle and never had any issues/problems. Just allocate a space for them to be be stored and all is good. In my patrol I store them behind the front seats in 'gap' that separates the cargo area. The panels themselves are pretty tough given they are made with tempered glass.

cheers,
george.
 
I was thinking the same thing regarding the hinge. There is plenty of aluminum frame to attach some sort of hinge.

I don't really want to mount it to my RTT. The way it stores now is actually perfect. It allows me to have the panel up against the fridge. The fridge can still slide in and out very easily, but now i can stash all kinds of stuff between the panel and the sliding window. Makes a nice storage place for now.... but eventually i was going to mount OBA in that location. So then i'll have to find another place for the panels.
 
george_tlc said:
I have a chinese TRUE MPPT controller with DC : DC conversion and it works great and price was in the $100 range.

cheers,
george.
Click to expand...

George, could post up a link/details on this charge controller you have please.
 
2016 new 20A MPPT 12V/24V Solar Regulator Solar Charge Controller LCD Display

Is an example of the TRUE mppt controller I'm using. You have to be very careful since a lot of the cheap ($10 - $20) ebay mppt controllers are outright lies and are just PWM controllers.

A real mppt controller requires a DC to DC converter (so there's quite a lot of electronics inside including a large high frequency inductor for the buck switching converter) to take the higher solar panel voltage and convert it to battery charging voltage while tracking the maximum power delivery point of the solar panel.

cheers,
george.
 
George is right on the money with cheap MPPT chargers, there are tons of outright fakes, almost as bad as the 18650 battery counter fitting going on, buyer beware!
 
george_tlc said:
2016 new 20A MPPT 12V/24V Solar Regulator Solar Charge Controller LCD Display

Is an example of the TRUE mppt controller I'm using. You have to be very careful since a lot of the cheap ($10 - $20) ebay mppt controllers are outright lies and are just PWM controllers.

A real mppt controller requires a DC to DC converter (so there's quite a lot of electronics inside including a large high frequency inductor for the buck switching converter) to take the higher solar panel voltage and convert it to battery charging voltage while tracking the maximum power delivery point of the solar panel.

cheers,
george.
Click to expand...


George-

How has this MPPT controller been working? Does it provide any realtime monitoring data, or do you have to have a separate charge condition meter? Looks like direct ship from China- how long did it take to arrive?

Thanks
 
abuck99 said:
George-

How has this MPPT controller been working? Does it provide any realtime monitoring data, or do you have to have a separate charge condition meter? Looks like direct ship from China- how long did it take to arrive?

Thanks
Click to expand...


Not George, but I did stay at a Holiday Inn Express. I have one of these controllers too, and it works quite well. It's the same as the "Eco-Worthy" controller you can buy on Amazon. You can program the voltages that it charges to, or use the default programming. It also gives you the option of 24 volt operation, but if you use that option, you need a panel with an VOC (voltage, open circuit) greater than 30 but less than 44. I would basically advise that this is a 12 volt unit only, though with 2 series wired "12 volt" panels, it would work perfectly on 24 volts.

The one thing I don't like, is that it stays in bulk mode until it hits the voltage limit, then drops to absorb voltage, and then only stays there a few seconds, then drops immediately to float. Most controllers stay in "absorb" mode for several hours before dropping to float to assure a complete charge. I don't know if that's a major problem or not, but the unit's firmware needs a tweak, I think.

It does have built in monitoring of battery voltage (innacurate-it's optimistic by 0.3v), amperage (accurate), cumulative watts, and displays mode-ie "bulk, Absorb, float" and has two other modes "Sleeping" and "Snoozing". Sleeping means no sun, and snoozing means under 0.5 amps of charging current.

It also has a bizarre feature where it will calculate the "extra" efficiency of the MPPT mode vs the PWM mode of operation. This I think is just for the machine to tell you how great it is vs your old PWM controller.

Anyway, I've had fun playing with mine.

There's a new kid on the block in sort of inexpensive MPPT controllers that get good reviews. That's the Epever MPPT controller. It looks nice enough I'd like to try one.
 
Yeah, it works quite well for the $. I've run it in oz and had nice cold beer even when it was well over 100F in the shade - and after all that is really all the matters :)

The Epever looks like another decent option.

cheers,
george.
 
Thanks for the reply Drew- and George. That EpEver unit looks promising. Priced a little less than the Ecoworthy- little cleaner looking. I just looked at a review on youtube about it., The guy takes it apart and notes the internal components:

Im in the process of building a portable solar system. This has been very helpful. Thanks.
 
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