Adding solar panel for Micro Minnie FLX

[Marine359]

This is a what a parallel connection of three equivalent 100w panels looks like. Just trace the wire from the panel on the right, and note that the negative lead is connected to one 3-way harness, and the positive to the other 3-way harness. The other two panels are connected the same way. Then the harnesses are connected to the gland. With two panels your harnesses will have two panel connections instead of the three shown here.

[mfouts]

Thank you, I will climb up and see what I have.

[electric]

Originally Posted by mfouts

Today I checked voltage at the power on the side receptacle and it read 44 volts. I assume that means that it is ran through the controller that services the roof mount panels.
If I wanted to use as is, is there a downside provided i use a compatible panel?
How do I determine what compatible panel I need?

44 Volts means the port is wired in parallel to existing panels and also confirms that existing panels are wired in series 2x 20V each.
This is the worst case scenario and makes it almost useless, because you have to use at least 2x 20V panels externally to match voltage with stock panels, which makes for a large and heavy solution, hardly called portable.
Even worse, if you roof panels are under shade and their voltage drops, while your side panels are under full sun, there is a chance that lower voltage side won't make any power at all.

If you really want to maximize use of solar power I strongly recommend to rewire the port and add a 2nd solar controller for external panels, independent from stock panels and controller. This way you can use any panels and both sets of panels will make most power as they would go thru their own controller. Two controllers will be in parallel at the battery side, combining their power to better charge the battery.

[Marine359]

@Electric
Two controllers work much better when one set of panels is on the roof and another set of portable(s) through a sidewall port. The controller connected to the sidewall port doesn’t need to be as big as the controller that services the roof. A 75/15 mppt will be sufficient to service most any portable panel, or two portables in series. And a 75/15 is not very expensive and gives you total flexibility.

[mfouts]

Will the controllers that come with the panels work?

[Marine359]

Originally Posted by mfouts

Will the controllers that come with the panels work?

Don’t know which panels and which controller you’re referring to. Is it the existing installed inside controller, an on-board controller for portable panel?

[mfouts]

Just as an example the Renogy 200w suitcase comes with a 20 amp voyager controller. would it be necessary to add a different controller?
https://www.renogy.com/200-watt-12-v...BoCoBcQAvD_BwE

[Marine359]

Now that I know you’re talking about a portable with built-in controller, the answer is: you don’t need to wire it to the inside controller. As a matter of fact, you have to ensure the wire from the sidewall port is wired or (re-wired) directly to the battery through an inline fuse. Keep in mind that the Voyager is a PWM controller which will not perform as well as a mppt controller. Additionally a portable with a built-in PWM controller has to placed pretty close to your camper. Any wire length between battery and panel will begin to deteriorate charge amperage due to voltage drop as the cable length increases. When you mount a charge controller next to the battery there is virtually no voltage drop even with a very long cable. This because you’re sending high voltage and low amperage which the controller converts to charge amperage. When you use an on board controller, you lose the high voltage and convert it to amps. Typically the on board PWM should have a cable length of 10ft or less, whereas 30ft is a typical cable length for an mppt next to the battery. This makes all the difference in the world when you’re in a shaded campsite and you’re trying to place your portable panel in the sun.

[mfouts]

So.....My best bet is to locate wires from external sidewall port and add a mppt controller to that? Does the inline fuse go between the port and the controller or the controller and the battery? What type/size fuse do I need? Do I attach wires from the controller directly to positive/negative of the battery?
At that point I would look for a portable panel without and controller?
I see there are quite a variety of MPPT controllers, is there something specific I should look for?

Does make it difficult as I am keeping my trailer at a storage facility so I can't walk out and see what we are talking about plus I am not all that bright.

[electric]

Originally Posted by mfouts

So.....My best bet is to locate wires from external sidewall port and add a mppt controller to that? Does the inline fuse go between the port and the controller or the controller and the battery? What type/size fuse do I need? Do I attach wires from the controller directly to positive/negative of the battery?
At that point I would look for a portable panel without and controller?
I see there are quite a variety of MPPT controllers, is there something specific I should look for?

Does make it difficult as I am keeping my trailer at a storage facility so I can't walk out and see what we are talking about plus I am not all that bright.

No offense, but based on your questions I don't recommend you doing any of this yourself. Definitely DO NOT attach anything directly to the battery!!!

First, external port needs to be "un-wired" from whatever it's currently wired to, so you don't ruin your roof solar and stock controller.

Then, wires coming from external port, which are now disconnected, should be connected to the input side of your new MPPT solar controller. Negative wire connects directly, positive wire connects thru a 30A fuse or breaker.

Then, output side of the new controller gets connected to a 12V DC bus, which is a common power circuit coming from the battery thru the main DC disconnect. It's the same circuit where stock controller output is connected to, thru it's own 30A breaker.

I posted a diagram of this rework earlier in this thread. If this simple diagram doesn't make sense, please don't proceed without experienced helper.

[mfouts]

No offense taken, its more than obvious you all are much smarter than I am. Its likely that I will not pay to have this done so if I don't feel I can accomplish it without creating additional problems I will bag it.

electric, I did not see the diagram in this thread, am I missing something?

Thanks everyone for contributing, I do feel I am understanding a bit more.

Marine359, also thank you for your service. My father in-law is a proud 84 year old Marine and recalls it as being some of the best times in his life.

[electric]

Sorry, I got mixed up in 2 different, but related discussions.
Here is the link to my post with the diagram

In that diagram I added 2nd controller externally, so people can use a kit like that Renogy you linked, or GoPower make similar kits.
But you can move the controller to be inside, behind the port, then only panels would be external. Many ways to do this, depends on what panels you pickup and how far from the RV you want to place them.

[Marine359]

An easier and inexpensive way to wire two controller outputs is to use a fuse block. The fuse block will accept any size of spade fuse from 5 amps to 50 amps. A fuse block can also be used to wire accessories into your battery circuit. In my case, I wired up two 12v/usb outlets next to the bed that are more accessible. And I wired in a 15 amp HD 12v outlet in the pass thru to run my transfer pump. Finally, wired into the fuse block my thermostatic heating mat and switch that I wrap around the battery. The size of the fuse should be equal to the maximum output amperage of the controller. Note in this picture my fuse block is sitting to the right of my two controllers. My battery is to the right of my inverter/charger. All wiring from panels all the way to controllers should be 10awg.

The wires from the roof should also be connected to a breaker before they go to the controller. This allows you to disconnect your array from the circuit. No need for that with portables, as they simply unplug from the sidewall port. From the fuse block, 6 awg wiring connects to my bus bars which in turn are connected to my battery.

[mfouts]

I am pretty sure I understand the diagram as well as understanding that I need to wire my system up from what it is currently to near what the diagram says.
I am looking at removing the solar at the side wiring from the current controller and wiring it to this controller.
https://www.victronenergy.com/solar-...100-20#manuals

From there I am looking at this breaker to place between the controller and battery.
https://www.bluesea.com/products/713...face_Mount_25A

At that point is it ok to run positive wire from breaker directly to battery and negative directly from controller to battery?
Would the 6awg wire be acceptable from controller to breaker and then to battery?
Does the negative wire also need to be 6awg?

[Marine359]

Blue Sea is good product, but that breaker can only protect one circuit. And resettable breakers will fail over time. I use a resettable breaker between the roof array and its 100/30 controller primarily so I can disconnect the array from the 12v circuit. But between battery and controller I use fuses. Much safer. If there’s a problem, the fuse will blow, which can be easily replaced. If you’re just protecting the a single circuit wired between the controller and the battery, better to get an inline fuse sized to match the max amp output of the controller. These holders accept replaceable spade fuses:

10ga Fuse Holder, 2 Pack MUYI Inline Fuse Holder 10 Gauge Fuse Holders 12v Waterproof Pigtail Blade Fuse Relay with 40AMP ATC Fuses https://a.co/d/98nWOLn

You do not to use 6awg wire from controllers to battery. 10awg is more than sufficient for your setup. I use 6 awg from fuse block to battery because it is carrying the current from two controllers which can be up to 45watts. A 100/30 and a 75/15.

You’re oversizing a bit on the controller for the sidewall port. I’ve got a Victron 75/15 for that choir, which is big enough to support two 100 portable panel in series or parallel. If you have two 100w portable panels, it’s best to wire them in series, so you won’t have voltage drop over a 30ft cable. That would send approx 36v @ 5 amps over that wire.

And, yes positive a negative wires in the same circuit must always be the same gauge.

[mfouts]

Originally Posted by Marine359

Blue Sea is good product, but that breaker can only protect one circuit. And resettable breakers will fail over time. I use a resettable breaker between the roof array and its 100/30 controller primarily so I can disconnect the array from the 12v circuit. But between battery and controller I use fuses. Much safer. If there’s a problem, the fuse will blow, which can be easily replaced. If you’re just protecting the a single circuit wired between the controller and the battery, better to get an inline fuse sized to match the max amp output of the controller. These holders accept replaceable spade fuses:

10ga Fuse Holder, 2 Pack MUYI Inline Fuse Holder 10 Gauge Fuse Holders 12v Waterproof Pigtail Blade Fuse Relay with 40AMP ATC Fuses https://a.co/d/98nWOLn

You do not to use 6awg wire from controllers to battery. 10awg is more than sufficient for your setup. I use 6 awg from fuse block to battery because it is carrying the current from two controllers which can be up to 45watts. A 100/30 and a 75/15.

You’re oversizing a bit on the controller for the sidewall port. I’ve got a Victron 75/15 for that choir, which is big enough to support two 100 portable panel in series or parallel. If you have two 100w portable panels, it’s best to wire them in series, so you won’t have voltage drop over a 30ft cable. That would send approx 36v @ 5 amps over that wire.

And, yes positive a negative wires in the same circuit must always be the same gauge.

Thanks a bunch, very helpful. I had considered the fuse holder but not sure that would be sufficient, I would rather do that anyway.
I was looking at the 75/15 controller, maybe just wasn't clear in the link.
Would it make sense to put the controller next to the current controller, assuming I can find the sidewall port wires close to that?
Once the fuse is in line is it ok to connect direct to battery?

[Marine359]

Since we’re talking about sidewall port here, there is no current in that line if no panels are connected to the port, so its ok to go ahead and wire the input side of the controller. However, there will be current leaving the battery (the output side of the controller) when you hook it up. Therefore, it’s always advisable that you turn off your battery if it has a switch, or disconnect the positive cable from the bus before wiring the output side of the controller. Before doing any work on the roof panel circuit, always disconnect the panels from the gland, because solar arrays are always “hot”, and you could shock yourself if you accidentally touch a bare wire. It doesn’t matter where you mount the second controller, but try to get it as close to the battery as possible. Just use the amount of wire left over from when you disconnect the sidewall port from the existing controller. Mine are together because it was easier to wire them both to my fuse block, and it makes them more accessible and both can be protected with the same sheet of lexan.

Correction in my preceding post: I meant 45amps not 45watts.

[electric]

Originally Posted by mfouts

Once the fuse is in line is it ok to connect direct to battery?

If by "direct" you mean an actual terminal bolt on the battery lid, then no, don't connect anything extra to the battery terminals. Doing so adds risk of compromizing torque and reducing depth of threaded connection, and also bypasses the main DC breaker.
You should find a suitable ground stud for new negative connection and some accessible stud to attach a positive connection on one of the breakers, which is already connected to the main DC breaker.
I also don't recommend adding directly to the main 250A DC breaker because it has large diameter studs with difficult to access nuts, so while messing with it you could compromise those connections.
In general, don't mess with any large bolted connections if at all possible, as those carry up to 250A and could burn or melt if not properly torqued.

[Marine359]

Thanks for chiming in @electric
Bus bars always much better for battery connections.

[mfouts]

There has to be a connection to the battery at some point. How do you attach a bus bar to the battery?
I have numerous Jeeps that I have attached a winch, running lights, and other accessories to the battery per instruction and they have been working fine for years.