Solar panels in a series?

[SanDiegoChip]

We are wondering if these panels can be hooked up to each other in a series by running the wieres to one and then another panel?

We have just purchased two Kyocera Solar KD-135GX 135 Watt 12 Volt Solar Electric Panels and one Solartech 85 Watt Multicrystalline Solar Module.
We purchased them from solar-electric.com/ and they said we need a Midnite Solar MNPV6 Solar Panel Array Combiner box. So we also purchased one of those.
We have another Kyocera Solar KD-135GX 135 on the dodger that is now set up directly to the controller.


During instalation

The one on the dodger will also need to be hooked to the other three by the box or?

I am wondering if the person at solar-electric did not understand me. It could be they are corect but we would like another openiomn We would like to run one wire or two from one panel and then from that panel to the next panel and so on. That way there would be two (+ - ) wires coming down from the bimini.



Our boat neighbor has the older style panels with one wire and he has two panels. One is hooked to the other then to the controller.

If we set it up to the box and the box is in our lazarett then we will be running six wires down from the bimini. These are not small wires.
I am thinking the good thing about this is that each panel gas protection with a breaker. Also if one panel should fail it would not affect any others.
However I am not sure I know what I am talking about.










During instalation

[AdamLein]

Do you have a 24volt DC electrical system? If not, it's not clear why you would want to hook up your panels in series.

As for whether it can be done, it looks to me like those panels have some proprietary plugs connected to them. To hook up your panels in series, you'd have to cut off those plugs and connect the negative terminal of one panel to the positive terminal of the other. The remaining positive and negative terminals could be reattached to one of the removed plugs.

Seems very unlikely that this is something you should do.

[SanDiegoChip]

OK it would be Parallel wiring.
We have
3 – 135 watt panels
1 – 85 watt panel
We have a 500 watt controller.
So we want the four panels to total the 485 watts going into the controller.
If we go with this install using the box each panel will connect to the box (to a breaker) then the box will have two wires (+ -) that will connect to the controller.
We were just not wanting to run the six wires down into the boat from the bimini. If we wired the panels in parallel there would only be two wires going into the boat from the bimini not using the box.
I guess this whole thing is bit of splitting hairs as it just not that big of a deal.
We will run the six wires into the boat using a through deck fitting and be done with it.



Thanks,
Chip

[ebs001]

I think you mean can they be hooked up in parallel ie + to + and - to - and yes they can. If you connect the panels in series you will have 24 volts.

[AdamLein]

You can hook up the panels in parallel. Their amperages will sum. Make sure the wire that takes the current to the batteries is big enough for the maximum current the panels will all put out together.

By the way, I count 490 watts, not 485.

[Undadar]

I am relatively new to solar and am trying to learn. With that in mind, someone please correct me if I am wrong.

You can wire the panels in series to increase the voltage or parallel to increase the amperage. The 3024i charge controller appears to expect either 12 or 24 volt input. With that in mind, wiring the panels in series is not an option (as the voltage would be too much for the controller). So, I'd wire the panels in parallel and set the charge controller for 12V input.

The combiner box is completely new to me. However; it appears to offer some benefits - particularly in a home type environment where there are many more panels that we typical fit on a boat. I believe it is optional in your case. As previously noted, if you wire the panels in series, you probably need to use 10 gauge wire for the run to the charge controller (depending on distance).

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[hellosailor]

It looks like their "combiner" is just a breaker box with bus bars, and frankly I'm not sure there's any need or use for it. Why wouldn't you just combine (parallel) all the panels into a small watertight junction box on the bimini, and bring two heavier power cables down into the boat?

[mitiempo]

You don't need the combiner box. Along with it being designed for fairly large arrays, much larger than you have, it is designed to use non-marine breakers.
http://www.midnitesolar.com/pdfs/MNP...ions_Rev_A.pdf

Parallel the panels at the bimini as hellosailor posted and run 2 larger wires into the boat, sized for minimal loss at whatever distance it works out to be.

[noelex77]

My understanding is the 3024i is limited to 30A. Under ideal conditions your panels are going to exceed this. I think the 3024 self limits so should not be damaged by the current (but please check), but it seems a shame to throw away power even if it will only be a small amount.
The other problem is the 2 different types of panels you have. These will not share the same Power point making the regulator less efficient. Under some circumstances MPPT regulators can become confused with different panels and lock on to a very wrong power point, this can waste a lot of power.
You could solve both problems by using a second small regulator and feeding the Solertec panel through this.

[SanDiegoChip]

Originally Posted by mitiempo

You don't need the combiner box. Along with it being designed for fairly large arrays, much larger than you have, it is designed to use non-marine breakers.
http://www.midnitesolar.com/pdfs/MNP...ions_Rev_A.pdf

Parallel the panels at the bimini as hellosailor posted and run 2 larger wires into the boat, sized for minimal loss at whatever distance it works out to be.

OK I just canceled my order for cabling for these three panels as they were long cables. I can return the combiner box also with the breakers.

I did order a 30’ #10 cable so running the panels below as I was originally going to put the combiner box on top of the bimini so I am OK with the larger cable, curt in half 15’ should be long enough.

The junction box seems the way to go.
Now to find a junction box
Thanks,
Chip