Adding portable external solar to built-in solar (2021 320S Boondock)

gbod

We have a 2021 320S Boondock with the built-in solar.  It also has solar port on the battery tub to add an external solar panel,  (I believe it’s an SAE connector?). Is there any thing special I need to do, other than plug it in?  I’m assuming I will need a panel with a built-in controller, (like one of the zamp “regulated” models?).   Do the built-in and external solar panels work together additively?  Are there any settings I need to change on internal Victron controller to make it work?  I read somewhere that the Victron solar controllers would throttle down charging from the built-in panel if another external  panel was plugged into the battery box connector, and the only way to get an additive effect of the two panels is if they were both physically wired through the same controller, true or false?   Thanks to anyone that might be able to shed some light on this topic for me.

gbod

Answer found here https://tab-rv.vanillacommunity.com/discussion/12663/how-to-connect-add-on-solar?fbclid=IwAR2mw2ukDbG2gYg7rTDwP9u3tubuk-0jSjtpWP1JXEcSYHzCP0FTPXeoSSc

pthomas745

You can attach any solar panel to the SAE port.  As long as the controller's  "battery" output can have a cable connected to it with the properly wired SAE plug, it will work.  Very easy to figure out, and there are many options for different cables these days.  I just use an ordinary SAE cable, and, with proper wiring, it works just fine with no special (meaning "expensive") cables or adapters.

Sharon_is_SAM

@gbod - also, besides being able to use 2 different solar sources with 2 different controllers to charge the battery, the battery receives a charge from your tow vehicle and built in solar simultaneously going down the road.  Or even from built in solar and the charge from your converter via a generator.  

Looks like you are all set!

gbod

Paul and Sharon, thanks for your kind and thoughtful contributions here and over on the FB groups.

Denny16

Another option, is to add a Victron MPPT (10 or 15 depending on the size of your portable panels) solar controller, like the one already installed in your TaB.  Then you can get lower cost portable so,ar panels that do not have a built in controller.  Then the two sets of solar panels via the MPPT controller can be linked using the Bluetooth App.  A 200 watt set of panels would need a MPPT15, 100-140 watts would work with the MPPT10 that comes with the TaB320.
cheers

ColoradoSun

Having a the portable panel wired to a Victron solar charger would be ideal since you can monitor everything via the Victron app. I elected (at least for the time being) to just use a 100W Renogy suitcase panel with its own charger. I can indirectly check its output using the Victron battery monitor we added.  Not as efficient but it is works and is simple to do. I considered replacing the inexpensive charger on the Renogy panel with a Victron charger but the Victron chargers are not waterproof and need to mounted indoors. 

CharlieRN

@gbod - We also have 2021 320 BD with the factory solar. As the other replies to your query indicate, the output from the additional panel can indeed just plug into your battery through the SAE port, as long as it's via a it's own controller.

Our BD also has the stock 80 Ah battery, which we decided to augment with additional solar charging rather than upgrade right off the bat. To that end I ordered a Renogy 100w solar suitcase setup that was very attractively priced at just over $200. The kit comes with it's own waterproof controller (though the older PWM variety), adjustable stand, cabling and a carrying case. The hope is that the additional charging capacity will keep the stock battery sufficiently charged to allow a few days of boondocking. Only time will tell if this is a viable alternative, but even if storage capacity needs to be upgraded down the road, the additional solar panels will still be worth having.

Basil48192

@gbod - I have a 320S with factory solar which I love...except when I boondock in the middle of the woods with a lot of shade.  I just added a 200W Renogy suitcase and, as Denny16 said, added a second Victron controller.  Like a lot of others on this forum, I mounted the controller inside of the propane tub.  I added some weather stripping to the lid of the tub and added a quick-disconnect with MC4 connectors on the outside of the tub.  So far, it works great in my driveway!  I'm able to access both my original controller, the new controller and my battery monitor from my phone.  

lkc001

I still have some confusion on the "Zamp ready" solar if someone doesn't mind.  I have a 2017 Tab 320s.  I Do NOT have factory installed panes, but it does have the "Zamp" port on the outside of the tub. My question is, since it says "Zamp ready" I could just get some "Zamp" portable solar panels and plug in directly to the ports and it will start charging the batteries, in theory?  If it is "Zamp ready", does the trailer already have a charge controller or is that an additional piece of equipment needed?  If I were to get a less expensive solar suitcase with built-in charge controller, would I need to have the wiring reversed at the battery since "Zamp" is wired reversed from the factory?  Would I also need different cables or adapters--I think I read somewhere that Zamp cables use a different plug than other solar cables?

CharlieRN

I'm no expert, but as far as I can see, the Zamp and Society of Automotive Engineers (SAE) connectors are essentially identical, with no functional difference between them. I often hear however that they are wired differently, meaning that the positive and negative connections are reversed.

Yet the SAE port on my 2021 T@B 320S BD has its positive feed terminating in a male fitting that is shielded in the port - the same as the photos I've seen for Zamp connectors, including the the one in this informative thread on this forum: https://tab-rv.vanillacommunity.com/discussion/6230/zamp-solar-connections-explained   This makes sense as the it makes the positive terminal on the SAE (or Zamp) mating plug, female, shielding it from accidental contact with a ground (see photo in linked thread).

You should be able to plug the output from the controller of a solar suitcase to your battery via the port on your T@B regardless of whether its a Zamp  or SAE and even if the polarity is reversed (though that would require a reversing plug or some rewiring). It's very important that you get the polarity right before plugging things in! 

Because I've added the Bradley storage boxes, I will need to re-locate my battery port, since the DS box blocks access to it. I'm torn between using an SAE port or  MC4 connectors as @Basil48192 did.

gbod

@CharlieRN We added the Bradley boxes also, so adding a port somewhere else is on my to-do list.

gbod

@Basil48192 Very cool... giving me some new ideas!

Sharon_is_SAM

@lkc001 - not sure if you just bought a 2017 model, but if so, you need to make sure the wires for the battery terminals are the correct polarity and then you can plug in any solar panel with built in controller that you want.  Just make sure that the positive lead of the solar panel plugs into the SAE hole that corresponds to the positive lead on the battery - same with the negative lead.  

Your TaB does not have a built in controller.  You either buy a suitcase with an attached controller or you buy a suitcase separate from a controller.  If you buy a separate controller, it is not as plug-n-play.  

Zamp is not wired reversed from the factory - if you read the link provided by CharlieRN it should be clear.

If you went with a different brand like a Renogy that uses MC4 adapters, you would need a simple MC4 to SAE adapter - no biggie.  By now, Renogy may even have an SAE connector.  I like Renogy and we use their products.  They will hold your hand through your set up - great customer service.  Nice to be able to talk to someone.  

I still have some confusion on the "Zamp ready" solar if someone doesn't mind.  I have a 2017 Tab 320s.  I Do NOT have factory installed panes, but it does have the "Zamp" port on the outside of the tub. My question is, since it says "Zamp ready" I could just get some "Zamp" portable solar panels and plug in directly to the ports and it will start charging the batteries, in theory?  If it is "Zamp ready", does the trailer already have a charge controller or is that an additional piece of equipment needed?  If I were to get a less expensive solar suitcase with built-in charge controller, would I need to have the wiring reversed at the battery since "Zamp" is wired reversed from the factory?  Would I also need different cables or adapters--I think I read somewhere that Zamp cables use a different plug than other solar cables?

WayfaringStrangers

I might be confused, but need to be clear. I have a 2021 BD with solar on roof - I also have a Zamp suitcase - do I need to change anything to use both?
Sorry if this is redundant. 
Thanks, Bob 

Sharon_is_SAM

If your Zamp has a built in controller, you are probably all set.

 Make sure the battery positive that connects to the port positive lines up with your Zamp plug positive.  

pthomas745

There is no "Zamp appropriate" wiring of an SAE plug.  The "positive wire enclosed inside the plastic part of the plug" is exactly the way it is supposed to be wired.  The connector on the trailer is not "reversed polarity" or "wired backwards".  It is wired for a proper SAE connection. The confusion comes because the controllers are "bare wire" connections in most cases.  Imagine how simple it would be if the controllers came with an SAE port.  You would have a cable that would only plug in one way. (I've "hard wired" SAE plugs into my controllers). 

Rant complete. 

There are now many many cables and connectors that are properly set up for the SAE port.  It is much easier to deal with than 5 years ago, when Renogy wouldn't even discuss how to wire my Renogy panel to the SAE plug.  Three months later, they were selling a 35 dollar "adapter!"  Once I learned (with help from that link up in the thread) how to wire my controller to the trailer, I was amazed at how simple it is.  Most of the internet babble about the port is just...babble. 

So...don't let the port throw you off your solar plan.  It is easy to deal with.

WayfaringStrangers

Thank you both

Sharon_is_SAM

Thank you @pthomas745.  I think we did end up changing the leads at the battery because of the MC4 to SAE adapter we used.  

Basil48192

@WayfaringStrangers - I think the disconnect on the propane tub must be only on the later 2021 models....I had to add mine.
You need to look at the wiring inside of the tub to see how and where the Zamp connector is wired.  My guess is that there is not another controller and the Zamp connects directly to the battery.  If that is the case, you will need to buy a suitcase model with its own controller or buy a separate controller.  I chose the separate controller so I could mount it as closely as possible to the battery.  I also wanted the Victron controller with Bluetooth capability.  Can you provide a photo of the wiring inside the tub?

WayfaringStrangers

Hope I get pics right. Inside wires directly to battery 

Photos too large and deleted.  Please resize these and future photos before posting.  https://tab-rv.vanillacommunity.com/discussion/47/what-size-should-my-posted-forum-photos-be#latest

CharlieRN

Sharon_is_SAM said:

 . . If you went with a different brand like a Renogy that uses MC4 adapters, you would need a simple MC4 to SAE adapter - no biggie.  By now, Renogy may even have an SAE connector.  I like Renogy and we use their products.  They will hold your hand through your set up - great customer service.  Nice to be able to talk to someone.  

@Sharon_is_SAM - I recently ordered this Renogy 100w solar suitcase kit from the company's ebay website. The kit ships with alligator clips for the battery connection, so still no SAE connector. It is not a big deal to replace the clips with the appropriate connectors however, and the price was very attractive. If anyone is interested in the kit, I'd urge them to search around on the web for a discount code - I found one that reduced the already good offer from Renogy by another 20%. I hope to not have any questions regarding the set up, but it's nice to know that they have great customer service.

Sharon_is_SAM

@CharlieRN - you will need to add extensions.  Many of us have 20-30 feet of 10 gauge wire (I recommend marine cable for flexibility) to be able to park in the shade and move the panel into the sun.  Here is an MC4 to SAE connector that will work at the end of your extensions so you can forego the alligator clips:

lkc001

@Sharon_is_SAM Thank you so much for your helpful comments!  I bought my 2017 gently used in very late 2019.  Have been having fun doing simple mods and camping.  Maybe I just didn't describe my question or use the correct phrases, but it is my understanding that the Zamp wiring at the battery IS reversed from the factory and as you said, must be corrected so that positive to positive and negative to negative going from the Zamp port on the tub to the battery.  Once that is confirmed, am I understanding correctly that I CAN just get a portable solar panel with a built in controller and the correct adapter and then just plug straight into the Zamp port on the outside of the tub and I'm all set to go?  I have confirmed that the wiring from the Zamp port does go directly to the battery.  I am going to have my mobile RV tech check the polarities and show me how to do that when I have him do some other work for me.  

CharlieRN

Thanks @Sharon_is_SAM. I planned to replace the alligator clips and assumed the cabling in the kit was probably not sufficient but have been waiting for it to arrive so I can see what's actually included and how everything attaches before buying any accessories.

I also need to move or replace the SAE port on my storage tub because of the adjacent Bradley box. I'm debating about how best to do that and am considering simply leaving the port as is and adding another set of pigtails ending in MC4 connectors that exit the tub via the rear cutout.

The Renogy kit is scheduled to arrive today which will help me make up my mind as to which way to handle things.

Horigan

The MC4 connectors aren't great for repeated disconnects and connections.  You may want to go with an SAE port just for the convenience in making repeated connections.  Check it out when you get your kit.

pthomas745

@lkc001 Go ahead and check the polarity of the SAE port on the camper.  It is not "reversed" or "backward" or any of that.  It is simply a plug. Needs to be wired the right way to work.  Look at the plugs on your appliances at home.  They all have a "correct" way to plug them in. The SAE port is the same exact thing........The SAE cable that @Sharon_is_SAM would work perfectly, with no adapters or worries.

The port on the trailer was installed at the factory...exactly the correct way.

Sharon_is_SAM

lkc001 said:

@Sharon_is_SAM Thank you so much for your helpful comments!  I bought my 2017 gently used in very late 2019.  Have been having fun doing simple mods and camping.  Maybe I just didn't describe my question or use the correct phrases, but it is my understanding that the Zamp wiring at the battery IS reversed from the factory and as you said, must be corrected so that positive to positive and negative to negative going from the Zamp port on the tub to the battery. 

Once that is confirmed, am I understanding correctly that I CAN just get a portable solar panel with a built in controller and the correct adapter and then just plug straight into the Zamp port on the outside of the tub and I'm all set to go?  YES!

I have confirmed that the wiring from the Zamp port does go directly to the battery.  I am going to have my mobile RV tech check the polarities and show me how to do that when I have him do some other work for me.  

@lkc001  - Sorry this topic is so confusing!  

There is nothing wrong or magic about the wiring of the port.  Correct wiring of a Zamp port at the battery (or any port) is positive to positive and negative to negative, just as it should be and you should check it to confirm that it has not been changed by the previous owner.  The ports are not wired in reverse of how they should be wired as long as the red wire sits at the + battery terminal and the black wire sits at the - terminal.

To be clear, the ZAMP controller plug was designed to protect against shock by shielding (recessing) the positive pin and required an SAE port with an exposed male pin as positive.  The problem comes in when you want to plug into the SAE port using a plug end with an exposed positive pin.  It will not aline positive to positive and negative to negative correctly.  As long as you maintain the correct wiring connections (positive to positive and negative to negative) it really is just a FIT ISSUE!

To get around the FIT ISSUE, some owners alter the wiring at the solar controller, some change the wiring at the battery and others use multiple adapters.  In the end, to make it Plug-n-Play, you must have an SAE connector at the end of your controller cabling with a shielded (recessed) + pin and an exposed - pin.  

I don't know what kind of panel/controllers you have, but if you end up using MC4 connectors (appears pretty commonly used), here is a picture of what you will need.  These are available on Amazon.  

Here is the picture provided by nuCamp of the solar port.  You can see the male exposed pin is wired for positive (red) and the recessed female pin is wired for negative (black).

Also, here is a picture of what the SAE ends of a Zamp controller cable look like.  You can see how they aline with the solar port. (Thanks Verna!). 

lkc001

Thanks again @Sharon_is_SAM--that closeup of the port is also helpful.  This is just like learning the Alde for me--I'll study it for awhile, then all of a sudden it will click and I'll understand it and I will see that it wasn't that difficult!  I also need to get into the battery box again and trace wires.  I do know that the Zamp port is wired directly to the battery.  The battery box is also kind of a pain for short people--I have to stand on a step ladder & bend over to reach into  the battery box because I have the platform on the front with storage totes.  

Verna

@Denny16, it is best at this time to not confuse the owner. If the sticker on the factory installed port says “Zamp” then to call it otherwise will only confuse the owner more. 

My photo used by @Sharon_is_SAM says “Zamp” because it is for my ZAMP 200 watt solar panel. 

tybladesmith

As many others have suggested, buy an inexpensive multimeter and learn how to use it. Hopefully everything electrical on your T@b will in time become crystal clear for you. Enquiring minds want to know!