solar panels

Something like this from Deltran BatteryTender would be handy for many things battery related. I use one and have a lighter plug adapter so I can use my 12V air compressor.

Fuses and circuit breakers are there (whether in your house or trailer or anywhere else) to prevent accidental short circuits from causing fires by overheating the wiring.

Batteries produce hundred of amps when shorted. So if you connect your solar charge controller output directly to your battery and then get a short you can easily cause a fire by overheating those wires.

It is exactly the same as if you bypassed the breakers in your home panel board and ran a circuit directly to say an outbuilding. Unsafe and a violation of the electric Code. And yes the Code applies to RVs too. Pleas don't do it.

The advice to always use a voltmeter to confirm is sound. You never know who or when the wiring could have been screwed up by someone. There is a lot of confusion because there are two different wire color standards used for 12v systems in RVs. One is the old automotive standard, red pos, black neg. The other is the national electric code standard which, just like in your house, has black or red hot (in this case positive) and white neutral (in this case negative). You will find the original internal wiring in the trailer following this standard, as the NEC does apply to RVs.

This is all so confusing to some folks that things end up wired wrong on RVs a lot. That often leads to what we call "finding out where they hid the smoke". So, use the voltmeter to confirm what you have, assume nothing, and don't add to confusion for yourself or the next owner by messing up the color code further, use either one or the other standard and stick to it.

The other thing folks do a lot is not put in the correct fuses and or circuit breakers when they wire things in their 12v system. 12v battery systems are probably more of a fire safety concern that 120v systems because of the high currents available. But for whatever reason some people who would never dream of bypassing a breaker in their home panel board think they don't need fuses or circuit breakers on their 12v RV circuits. Totally wrong and a Code violation.

The picture you included does show a gender reverser plug in the middle of the coil at the top-left. Use a voltmeter so you know which terminal in your RPod is positive and which is negative (If you touch red lead to one connector and black to another and the reading is positive (e.g. 13.5v), you have the correct polarity. If you get a negative reading (e.g. -13.5v) then the polarity of the plug is opposite of what you connected. Switch the connection of your meter and verify that you get a positive reading with red and black leads. Note which connection is positive. Check the SAE connector on the wire shown above. If the red is going to plug in so red aligns with positive, fine. If not, then use the gender reverser plug to be able to flip the connection around so the red will connect to positive and the black to negative.

The solar ready port is just a connection to the battery. The solar charge controller manages it's own charging, the rpod converter is not involved.

So, you don't need to use that charge port, and many (most?) people don't. It tends to just add more wire resistance losses between your solar module and your battery. You can just connect directly between the solar charge controller and the battery via an inline or bolt on fuse at the battery + terminal. The charge controller can be mounted by the battery or in an adjacent storage compartment if you want.

If you do use the existing charge port take heed of the reverse polarity warning and use a voltmeter to be sure you get it right before connecting. It's been deliberately wired reverse to normal for that SAE connector type so that ppl think they have to buy a Zamp solar kit.