Thanks for the followup, @kevmon. Now I'm curious as to what prompted this apparently recent change in the wiring configuration, and why connecting to the battery directly vs. via the DC negative bus makes any practical difference.
Everything from the front tub goes through the trailer junction box on the frame and then to the inside of the TAB (at least in my '21). The negative circuit (wire) from the front tub goes to junction box #7 terminal, then from there to the negative bus bar besides the WFCO. The positive battery circuit (wire) from the front tub goes to junction box #6 terminal, then inside to the WFCO battery wire (also #6).
I also moved my batteries inside w/o cutting any holes for wires. You can splice into the the WFCO battery #6 wire. Ask if you need more details.
Thanks, All. SOLVED! It is indeed for the Alde. Here are the three wires coming in (second pic of wires from under wet bath area, my thumb on the three). The positive is from the junction box The negative two crimped wires at the battery are free from each other coming into trailer. You can see the one smaller cable running to the ALDE (loose in the ALDE pic). I'll attach it to a new negative bus bar from the new inside battery.
I suspect this is important for anyone changing batteries to inside. Make sure to look for the second negative.
All the rest of what you said, Yoshi, is correct on mine. I've been following your prior work. Thanks for helping the rest of us figure this out.
The Zamp backward-reverse-polarity-whatever-thing used to be a hot topic with early nuCamp T@Bs, when suitcases and other portables--mostly from Zamp and Renogy--were SOP for solar power in camp.
I agree with bergger's assessment of the typical arrangement of Zamp equipment but will emphasize to always verify your connections by visually tracing wires, checking continuity with a multimeter, or both. Don't rely on colors or assumptions about which pin is which.
This becomes particularly important when attaching non-Zamp equipment as plugs may fit but you end up crossing connections somewhere between your panels and your battery. Regardless of what you are hooking up, always confirm that through the entire circuit positive connects to positive and negative to negative and all will be well!
@Robermcm if you lift up the drivers side dinette cushion you will see a hinged access panel. The filter is right there. The filter is contained in a hard plastic frame that slides out of the built in groove.
@Robermcm Generally it won't be replacing something else. Most systems don't have this installed as standard (Unless your Tab came with the factory Lithium upgrade install). All loads and chargers get connected to one side of the shunt. The other side is connected to the negative of the battery. If the system doesn't have a shunt installed already, there might be a need for some cutting of wires and connectors being attached. The install is quite easy.
@mlk51 welcome and congratulations on your trailer. We're other 2017 t@b owners from the east coast of Michigan. I happen to be biased on the vintage (2017) being a good one.
Not sure if this is wise, but it worked for me. Please feel free to tell me this was unwise if you have an opinion. You won't hurt my feelings!
I was on fairly level ground. I unhitched, but left the chains attached to TV, and pulled forward slightly to clear hitch and set parking brake. I lowered the front of the Tab 400 all the way down and then lowered the back stabilizers until they just made contact with the ground. I then raised the front of the Tab until the wheels were off the ground. I lowered the front stabilizers to give it stability, and then changed the tire. It worked for me.
I think they will dance and dance and dance around this issue forever.
The tongue/stabilizer method works on my Outback just fine, no blocks needed. It is nice to know there is a spot under the trailer for a jack point should I need it.
Re: I can't find anything on this forum or on YouTube concerning T@B stabilizers