extra negative wire crimped to main on battery?

kevmon

Hi folks,
I am new here. I just got a T@b 320 and am looking to upgrade the batteries to lithium and move inside under the passenger-side seat. I am following a lot of the information you all have provided here, which has been extremely helpful so far. Everything makes sense. 

I can separate the solar connections from those going to the battery disconnect switch, and I know what inline fuses are.

My question is, on the factory battery connection that eventually goes to WFCO, one additional negative wire is crimped (same lug) with the primary negative wire on the battery terminal. I assume it may go to the junction on the trailer frame, but I'm unsure. Does anyone know? 

I am just thinking about how this may affect moving the battery. 
cheers,
Kevin

Sharon_is_SAM

It may be a ground to the Alde.  We had one added to prevent Alde fuses from blowing.

Yoshi_TAB

Hi,

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.  

kevmon

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. 

Yoshi_TAB

Hi, 

That same white  wire (from the Alde) in my '21 goes to the negative bus bar behind the WFCO..which makes sense to me.  So I'm clear, are you saying your white wire (from the Alde) leads out to underwet bath to the junction box and to the battery?  If so (but maybe I'm not clear on what your saying)..why would they do that?

kevmon

Yes, it makes no sense. It then comes back into the trailer and to the negative factory bus bar (-) as yours is installed. Seems like a lot of unnecessary wiring. 

Edited:I found this old discussion:
https://tab-rv.vanillacommunity.com/discussion/5813/running-a-ground-from-the-alde-to-the-battery

In the thread, Alde recommended a direct connect to the battery. This was from Alde:

"I think the proper fix would be to run a ground wire directly from our boiler to battery, this will fully ensure we are not getting a voltage spike back fed from some other appliance in the trailer. I have done this repair myself and I ran the ground wire to the trailer frame, I think as long as it’s not in the common ground block with other appliances that should prevent the ground side fuse from blowing."

Yoshi_TAB

Hmm..what year is your 320? Is it new from factory.    I seen a lot of posts with battery connection pictures and don’t recall seeing an Alde wire connection there.

kevmon

2023 new from the factory. 

bjn2

In our 2023, the extra ground wire goes to the plastic junction box for traveling lights and brakes under one side of the trailer's A-frame per @Yoshi_TAB 's comment. There's also a green positive wire that doesn't go to the tub, but exits with the other tub wires down where they penetrate the trailer. 

kevmon

bjn2 said:

In our 2023, the extra ground wire goes to the plastic junction box for traveling lights and brakes under one side of the trailer's A-frame per @Yoshi_TAB 's comment. There's also a green positive wire that doesn't go to the tub, but exits with the other tub wires down where they penetrate the trailer. 

Hmm.... Just when I thought this was going to be easy... lol. I will have to pull the tire and check everything more closely at the junction box. I'll update you whenever I can find time to look at it.  

ScottG

This is peculiar. It's unclear to me why the traveling lights and brakes would need a dedicated ground wire back to the battery. These systems are powered by the tow vehicle via the pigtail and typically do not involve the battery in any way.

Also, at least in previous model years, all connections were made via terminal studs in the junction box. Even if you did for some reason want to connect the traveling lights and brakes to the battery negative, you could do so at the terminal stud in the box without having to run a separate wire back to the battery. The photo below shows the arrangement of wires in the junction box. The labels are on the positive terminal stud, but the same connections apply to the adjacent negative terminal stud.

As noted in earlier comments, running a ground from the Alde directly back to the battery was previously prescribed as a solution to the frequent blowing of the Alde fuses, but that issue was largely rectified with the upgrade to the Alde 3020, which (I think) eliminated the fuse on the Alde's negative power leg. Direct grounding of the Alde cabinet was also kicked around as an early solution to the convector corrosion issue, but I'm not sure if that ever got much traction.

So, I'm left still still wondering exactly what the purpose of that second negative wire is. At first pass I'd have guessed a mod by a previous owner, but this case the T@B was fresh from the factory.

 

   

Yoshi_TAB

kevmon said:

bjn2 said:

In our 2023, the extra ground wire goes to the plastic junction box for traveling lights and brakes under one side of the trailer's A-frame per @Yoshi_TAB 's comment. There's also a green positive wire that doesn't go to the tub, but exits with the other tub wires down where they penetrate the trailer. 

Hmm.... Just when I thought this was going to be easy... lol. I will have to pull the tire and check everything more closely at the junction box. I'll update you whenever I can find time to look at it.  

Hi, 
Just for my curiosity..double check where the second pigtailed negative in the front box leads to. Doesn’t go to a solar connection?  A second battery?   Do you have a helper who can assist in running  a continuity check on what you think are both ends to confirm the other end. Maybe email Nucamp Tech support?
Good luck..RV wiring is often like the Wild West

B0atguy

I have a 2024 400 , and it also has that white Alde wire going directly to the negative terminal of the battery . My 24 also came the Victron bluetooth shunt to monitor SOG parameters . Its weird to me that this white wire would go directly to the battery negative instead of the Victron shunt side. I just installed  4 100AH Renogy smart heated batteries in parallel (400AH) , to replace the single 100AH Battleborn , and was unsure about that single white wire from the Alde. I hooked up that wire directly to the negative side of the battery bank just to be safe. Not sure exactly what its purpose is for Alde , so I left it where it is from the factory . If its to prevent voltage spike's , it makes sense that it should go direct to the battery negative. 

MuttonChops

B0atguy said:
I have a 2024 400 , and it also has that white Alde wire going directly to the negative terminal of the battery .

Confused Here.

Adding an Alde specific ground wire was a 'recommended fix' for blown fuses on the 3010 model Alde.

I'm very confused why nüCamp is installing an extra ground connection on the newer 3020 Alde units.  My 2018 has the 3020 and NO extra ground wire - - - and I've never had an Alde Fuse failure.

I question the "wire tracing method used".

Most likely my WAG would be the extra ground wire is related to the Solar Panels & Controller.

B0atguy

MuttonChops said:

I question the "wire tracing method used".

Most likely my WAG would be the extra ground wire is related to the Solar Panels & Controller.

In a 400 , the batteries are located pretty much right next to the Alde . There is no wire tracing method that can get confused . The white "extra" ground wire runs from the negative side of the battery directly to the Alde . Its pretty much cut and dry. There is no loom it can get lost in or anything . 
Tracing method is - grab the white wire on the battery neg. and slide your hand along said white wire directly to the Alde.  The wire is literally only a few feet long. 

kevmon

MuttonChops said:

B0atguy said:
I have a 2024 400 , and it also has that white Alde wire going directly to the negative terminal of the battery .

Confused Here.

Adding an Alde specific ground wire was a 'recommended fix' for blown fuses on the 3010 model Alde.

I'm very confused why nüCamp is installing an extra ground connection on the newer 3020 Alde units.  My 2018 has the 3020 and NO extra ground wire - - - and I've never had an Alde Fuse failure.

I question the "wire tracing method used".

Most likely my WAG would be the extra ground wire is related to the Solar Panels & Controller.

I'm not an expert, but I'll absolutely verify my wires beyond a tracing guesstimate. Having said that, based on the information I have, it appears to be a ground for the Alde on my Tab 320. Alde doesn't have an installation manual for the 3020 on their US website but does on the UK one. I assume the DC circuit is the same. In that manual, it states:

"The 12-volt supply to the boiler must be routed directly from the battery via the vehicle’s main switch"

The 16 AWG wire from the Alde is the only 16 AWG I see in the tub. This also fits BOatguy's direct connection in the 400. I will make sure to verify before doing anything. 

The solar wires on my 320 enter the trailer completely separate from junction box items—at a different entry point. It is straightforward to see that this is not related to solar--that I am 100% sure about. I highly doubt they would attempt to use 16 AWG for the solar controller connections. 

Finally, I've done something pretty extraordinary to understand this better. I've emailed NuCamp. lol. 

elbolillo

I have a ‘23 Tab 400. The factory install was a single LiFePo4 battery and the white wire was attached directly to the battery negative. I have since upgraded my install to a 4 battery bank with smart shunt. I connected the white wire to the negative bus bar.

The white wire is NOT (at least in this instance) and “extra” ground wire. It simply is the negative side of the 12v system which operates the Alde as @kevmon mentions from the install manual.

Here is a photo where you can see both the red (positive) and white (negative) wires that are connected to the 12v plug to provide power to the Alde.

kevmon

I Heard back from NuCamp about the "extra" wire running to the battery minus of my Tab 320
@Yoshi_TAB   @elbolillo @MuttonChops  @B0atguy  @Sharon_is_SAM @bjn2  @ScottG

My email: I have a question about the Alde. I see a 16 AWG negative cable running from Alde and going under the wet bath. I also see a 16 AWG cable on the negative battery terminal crimped to the main battery's negative connection. Is the Alde wired all the way to the battery (-) directly?

NuCamp response: "No, the mains system should be connected to the converter. What you are describing is probably the wire that is connected to the battery for grounding purposes. I hope this helps and if you have any other questions please reach out."

My email: Just to clarify, do you mean grounding for the Alde system? It's a smaller second cable crimped to the primary one on the negative terminal and appears to match the AWG of the ground coming off the Alde. The Alde installation manual suggests that there should be a direct connection to the battery's negative terminal to avoid voltage fluctuations. I know of one person with a Tab 400 that can see the direct connection from Alde to the battery because their batteries are inside. I want to verify this for the 320.

NuCamp response: "Yes, that is correct, it is grounding for the Alde system. We did this for both the 320 and 400." 

elbolillo

@kevmon The first response from NuCamp muddies the water. They should have been more specific. Yes, the positive red wire is connected to the converter and has a 7.5 amp fuse. The negative (or ground wire) goes to the battery.

For all the other 12v runs in the Tabs both the positives go to the converter and the negatives (or grounds) go to the negative DC bus bar behind the converter.

kevmon

@elbolillo Agreed, that is why I sent the follow-up. I asked about the neg (ground) going to DC system. It makes it easy for me to pull the entire thing into the trailer and add it to my new bus bar, which is powered by new lithium batteries. If I get fuses blowing, I'll go directly to the battery, but I prefer to have this after my shunt. 

elbolillo

kevmon said:

@elbolillo Agreed, that is why I sent the follow-up. I asked about the neg (ground) going to DC system. It makes it easy for me to pull the entire thing into the trailer and add it to my new bus bar, which is powered by new lithium batteries. If I get fuses blowing, I'll go directly to the battery, but I prefer to have this after my shunt. 

I have mine wired to my negative bus bar. That in turn goes to my shunt. I have had it like this for about a year and a half. No issues with the Alde blowing fuses.

ScottG

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.