External Solar Port on T@B 360

Hi, We have a '25 360CS and it was not connected to the solar controller.  It was connected directly to the battery.  I did a point-to-point wire verification, and it was not, at least in ours.

I don't think you'll be able to get a firm answer from this forum. You need to check. Mine was not connected to anything. Just remove the square head screws and lift off the panel underneath the driver side bunk. It's pretty easy to trace where the two wires end up. The fact that they are not connected is not necessarily bad. You may not want to combine mismatched panels on one solar controller. Ideally the best results come when all panels on a shared controller are identical. The good news is you can get a very reliable and inexpensive solar controller for your suitcase panel, in fact it may come with one. Mine did not, but I located the second controller in the camper so that the voltage is not down converted until right before it's used, which I think is slightly more efficient. That second controller goes then through the smartshunt as well. (POS to positive battery or positive bus, and neg to the load side of the shunt). The suitcase controller is the black box in the upper right corner. I did add pos and neg bus bars to reduce stacking of connectors on the shunt and battery itself, but those are not strictly speaking necessary. 

Great question. If you care about monitoring your production totals and history all in one place I suppose it would be useful. But if you have the portable wired through the shunt you can easily see if it's working and use that feedback to position the panel optimally. The suitcase panel is a backup / adjunct for us so I am fine with simple. If I really needed to know what it was producing I could do the math to compare the batteries state of charge gain with what the camper panels had produced.

rickpool said:

Would there be a meaningful benefit having both controllers the same brand (Victron) so that they can be managed together in a single app?  Or is a cheap, portable controller sufficient?

Using a Victron suitcase solar controller has the advantage of having the ability to network it with other Victron devices like your rooftop solar. When networked they optimize charging for efficiency and have all the battery/charging information available in one app. 

rickpool said:

I am trying to figure out whether the external solar port inside the Nautilus box (360 Black Canyon) connects to the Victron MPPT controller or directly to the battery?

nuCamp sizes the Victron solar controllers that they factory install to the wattage of the rooftop solar. In most cases, there will not be enough room (edit: capacity) left for an additional panel. Buying a suitcase panel without a controller and adding a separate Victron controller mounted close to the battery has the advantage of reducing the voltage drop that results from the long wire run between the panel and your trailer.

edit to add that the designation, like 75/10 on the controller stands for 75 volts and 10 amps. Exceeding the voltage will damage the controller, so you would have to be careful not to exceed the maximum combined PV voltage from your rooftop and a secondary solar suitcase. If you were certain that this would not be the case, then you could use the factory controller for both. The drawback is that it would never provide more than 10 charging amps to your battery.regardless of the amperage coming from the panels.

 I use my 12v SAE port as an easy battery connection more often than I use it for solar input.  It is where we plug in our compressor cooler as well as a maintenance charger during storage. 
I would not permanently install a solar controller in that line.

AnOldUR said:

I understand the ease of using the existing factory SAE port for things other than solar, but for accessories adding an external cigarette lighter port is a more versatile solution and won't conflict with solar charging. 

I have found those cigarette lighter connections to be very unreliable many times and avoid them if possible especially in higher current applications.

rfuss928 said:
I have found those cigarette lighter connections to be very unreliable many times and avoid them if possible especially in higher current applications.

I agree @rfuss928. The point was that most of the accessories like your 12V cooler come with this type of connection. Personally, I've been switching everything over to Anderson PP15 connectors. I was even able to find a new wire for our 12V cooler that had the PP15 on the end commercially available.

What I was trying to say is that having your solar controller between the battery and external port has advantages and that it's easy to add a second port for accessories. I shouldn't have specifically said a cigarette lighter port. I'm not a fan of SAE port either.