NuCamp recall for certain 2023-2024 nuCamp TAB 400, Cirrus 620, and 820's with the Lithium Upgrade

pthomas745

February 26, 2024 NHTSA Campaign Number: 24V150000

Battery Disconnect Switch May Overheat The incorrect battery disconnect switch can overheat, increasing the risk of a fire.

NHTSA Campaign Number: 24V150000

Manufacturer Pleasant Valley Teardrop Trailers LLC

Components ELECTRICAL SYSTEM

Potential Number of Units Affected 163

Summary

Pleasant Valley Teardrop Trailers LLC (Pleasant Valley) is recalling certain 2023-2024 nuCamp TAB 400, Cirrus 620, and 820 trailers with the Lithium Upgrade. The incorrect battery disconnect switch may have been installed.

Remedy

Dealers will replace the battery disconnect switch, free of charge. Owner notification letters are expected to mailed March 1, 2024. Owners may contact Pleasant Valley customer service at 1-330-852-4811- ext. 327.

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), www.nhtsa.gov.

NHTSA link

https://www.nhtsa.gov/recalls?nhtsaId=24V150000

Didn't find anything over at the NuCamp web page.  This showed up on a FB post earlier this afternoon.

ChrisFix

As I've been building a parts list to install a Multiplus 3000 in my 2021 T@B 400, one of the things I wondered about was the disconnect switch nuCamp uses. I had already purchased a 400 Amp disconnect and was planning on replacing the existing one for the exact reason this recall is happening...Glad I did!

Sharon_is_SAM

thank Thanks @ pthomas745.  I put it under the Service, Maintenance and Recall category.

Hammick

Well Damn.  Just bought a lightly used '23 400 with the Lithium upgrade done at the factory.  Taking it to a dealer will be a major PIA.  I'll probably buy the $60 disconnect and install it myself.  I'm wondering if the battery cables are undersized as well.  Not sure how you can get the disconnect wrong and the cable size correct.

I'll be keeping an eye on the amp draw with the Victron app.

ScottG

I need some schooling here. Although this recall doesn't affect me, I'm curious...

Most of the battery disconnect switches I've seen installed in T@Bs look pretty substantial. These are usually rated to handle voltage and current (amps) far in excess of anything a normal T@B would use. Anybody know what's happening in this case, or why it specifically matters in the case of the lithium upgrade? 

YanniLazarus

Interesting. Does this mean that when we increase our AH capacity with bigger or additional batteries that the stock disconnect switch is likely to be undersized? This is a pretty standard switch: 

Battery Disconnect Switch, Gioyonil 12-48V Master PowePower Cut Shut Off Isolator 275Amps

And it lists 275 amps... is that amp hours? 

ScottG

YanniLazarus said:

...
And it lists 275 amps... is that amp hours? 

Good question, but nope. Amp hours are a measure of battery capacity--specifically the amount of time a battery can sustain a current draw of a certain number of amps. Amp hours do not factor into the sizing of electrical equipment.

In contrast, the amount of current (amps) flowing through a switch or wire at any given time is important. This is to be determined by the number of electrical devices operating at any one time, and has nothing to do with battery capacity.

The rating on the switch would be the maximum current that the switch internals can handle without overheating (and thus creating a fire hazard) from excessive resistance. The same logic applies to electrical wires, which is why a larger current (i.e., greater amperage) needs to be carried by a larger diameter wire, and fuses prevent drawing more current than the equipment is designed to safely handle.

Unless I'm missing something (which is certainly possible), 275 amps is well in excess of any maximum current a camper is likely to be drawing. Hence my question of exactly why there is a problem with the battery switch in these particular models, and why the type of battery makes any difference.

Perhaps this has something to do with the inverter included with the lithium package?

Yoshi_TAB

Hi,

Really need to see the circuit wiring/design for the specific application, but 275 amps is in the ball park for a 2500W or 3000W inverter DC circuit.  

I have a 2000W inverter in my 320 and the calculation for fuse size (including inverter effeciency and safety factor) resulted in the use of a 225 amp fuse for the inverter circuit (seperate circuit than the charger or any other circuit).  My busbars and inverter ON/OFFswitch are sized appropriately for the larger amp inverter circuit.

2000W inverter assuming 90% efficency= 2200 Watts (2000/0.9)

Amps =Watts/Voltage=2200/12=185 amps

25% Safety Factor= 185 * 1.25 =231 amps

ScottG

Yes, good points @Yoshi_TAB, that's what I was wondering. A quick perusal of nuCamp info indicates the inverter in the lithium package is 3000W. By your calculations that would be almost 350A--exceeding the rated capacity of some switches. Makes me wonder if they didn't upgrade the standard issue switch when they incorporated the 3000W inverter. 

Denny16

Obviously an oversight with the added battery/inverter capacity.
cheers

Yoshi_TAB

ScottG said:

 Makes me wonder if they didn't upgrade the standard issue switch when they incorporated the 3000W inverter. 

That would be my WAG.  I once looked if there was any standard that RV man’fs have to follow like the NEC, but I found that RV building is like the Wild West with no standard requirements to follow for electrical design and building.  I  follow a couple of other Man’fs forums and incorrect wire and fuse sizing is a very common issue in RVs.  

ScottG

Wild West indeed. Following up on @Hammick's question above, now I'm curious about the wire sizing. A very cursory perusal of the topic indicates 4/0 is commonly recommended for a 3000W inverter (with a design load of 350A). Some say 2/0 is fine if the run is no more than a few feet, though going "by the book" I'm skeptical of that claim. I have no idea what nuCamp uses in their lithium package.

I realize this topic has been pummeled in a couple in other forum discussions, but since I personally don't want or need an inverter I haven't paid much attention until this recall surfaced and scratched my curiosity. Thank you for humoring me if these details have already been addressed elsewhere.  :-) 

ChrisFix

ScottG said:

Wild West indeed. Following up on @Hammick's question above, now I'm curious about the wire sizing. A very cursory perusal of the topic indicates 4/0 is commonly recommended for a 3000W inverter (with a design load of 350A). Some say 2/0 is fine if the run is no more than a few feet, though going "by the book" I'm skeptical of that claim. I have no idea what nuCamp uses in their lithium package.

I realize this topic has been pummeled in a couple in other forum discussions, but since I personally don't want or need an inverter I haven't paid much attention until this recall surfaced and scratched my curiosity. Thank you for humoring me if these details have already been addressed elsewhere.  :-) 

@ScottG
Victron (the manufacturer of the inverter used by nuCamp) for the 3000W/400AH Lithium package calls for a 400 Amp fuse, which means using 4/0 wire...and a much beefier disconnect than the standard one on our T@Bs.

YanniLazarus

So... if I put a 300WH lithium battery in my front tub and change nothing else on my 2020 320S (no inverter. And I recharge with a NOCO genius 10) am I okay? 

elbolillo

@ScottG NuCamp uses 2/0 wire for their install with a 300amp fuse. I installed my own system with the Victron Multiplus 3000w inverter and 4x100ah batteries. I consulted with Battleborn and they recommended 2/0 wire and a 300a fuse. That is what I used.

ScottG

YanniLazarus said:

So... if I put a 300WH lithium battery in my front tub and change nothing else on my 2020 320S (no inverter. And I recharge with a NOCO genius 10) am I okay? 

@YanniLazarus, as far as the amperage is concerned, yes, you are okay. 

Again, the amp-hour capacity of the battery has nothing to do with the amps (electrical current) flowing through the battery cutoff switch and trailer wiring. Current is determined by the number of electrical things you have running at any one time, and a typical 320--regardless of how big a battery you have--is fused for a maximum current of 30 amps. This is well within the capacity of the standard switch and wiring.

The problems start when you add an inverter, which draws a much bigger current in order to convert 12V to 120V. It appears this is the issue with the new 400 amp-hour lithium package. It's not the capacity of the giant lithium battery bank that requires the heavier duty switch and wiring, but rather the inclusion of a 3000W inverter as one of the package components.

I'm not familiar with the NOCO genius10 charger, but since it puts out a maximum of 10 amps and claims to be suitable for lithium ion batteries, that should be fine as well.

ScottG

elbolillo said:

@ScottG NuCamp uses 2/0 wire for their install with a 300amp fuse. I installed my own system with the Victron Multiplus 3000w inverter and 4x100ah batteries. I consulted with Battleborn and they recommended 2/0 wire and a 300a fuse. That is what I used.

Thanks, @elbolillo. According to this calculator, the 2/0 wire is sufficient given the short runs and 300A fusing. Assuming 90% efficiency and disregarding any safety margin, the 3000W inverter shouldn't exceed 300A even at full capacity. The standard battery cutoff (which appears to be rated at 275A) is probably just fine 99.9% of the time, but technically should not be installed on a 300A circuit. I'm thinking that detail is what initiated the recall for the 400s.

AnOldUR

YanniLazarus said:

So... if I put a 300WH lithium battery in my front tub and change nothing else on my 2020 320S (no inverter. And I recharge with a NOCO genius 10) am I okay? 

Just a note on the NOCO Genius 10. Last winter I upgraded from my AGM batteries to two 100Ah LiFePO4's. The NOCO had no problem charging either battery types, but it was slow. This winter I added a Victron 30amp charger to the tub. Three times faster makes a big difference. No regrets buying the NOCO. I still find other uses for it. 

YanniLazarus

Thanks, @AnOldUR. I've wondered about that. Unfortunately, my typical recharging power source is just a crummy old 15 amp house circuit. I think I'm stuck. 

ChrisFix

Victron recommends a 400 Amp fuse and appropriately sized wiring for the Multiplus 3000. 
If you're wiring with 2/0, then you must use a fuse that can protect it from melting, which is 300 Amps.

From Victron's Install manual:
4.2 Connection of battery cables
In order to utilize the full capacity of the product, batteries with sufficient capacity and battery cables with sufficient cross section should be used. See table.
12/3000/120
Recommended DC fuse 400A
Recommended battery capacity (Ah) 400–1200
0 – 5m = 2x 50mm2
5 – 10m = 2x 70mm2

ScottG

Recommendations clearly vary, though I'm inclined to give the nod to Victron since it is their inverter, after all. If I were doing my own install I would likely also beef up the circuit to 400A just to have that extra margin.

That said, if you follow the math it seems it would be a very unusual circumstance that one would pull more than 300A through the 400's battery circuit. Maybe if you were maxing out the inverter, and running a bunch of other 12V devices, and had a peak surge. Maybe. Then I guess you'd have a fuse to replace.

The point being, nuCamp's 300A design limitation--provided they incorporate a properly rated battery cutoff switch--should be adequate for the vast majority of power needs owners are likely to have in any real situation. I could be wrong, but I doubt it.  :-)

I'm not looking for an argument, just trying to address any recall-induced concerns (stated or otherwise) owners may have that their lithium package equipped 400s are insufficiently designed or unsafe.   

ScottG

YanniLazarus said:

Thanks, @AnOldUR. I've wondered about that. Unfortunately, my typical recharging power source is just a crummy old 15 amp house circuit. I think I'm stuck. 

@YanniLazarus, I'm not sure what specific model @AnOldUR has, but Victron (and probably others) make 30 amp chargers that plug into regular house circuits.

The 30 amp rating refers to the charging current, not the supply current. Since 30 amps at 12 volts is only 3 amps at 120 volts, you could go for that larger charger if you were so inclined.

rh5555

Just to be clear, in Victron's lithium setup with the Multiplus, where did they install the battery disconnect switch? Between the batteries and the Multiplus? Or between the battery/Multiplus group and the rest of the trailer?

elbolillo

rh5555 said:

Just to be clear, in Victron's lithium setup with the Multiplus, where did they install the battery disconnect switch? Between the batteries and the Multiplus? Or between the battery/Multiplus group and the rest of the trailer?

Battery/multiplus group, and the rest of the trailer

YanniLazarus

ScottG said:

YanniLazarus said:

Thanks, @AnOldUR. I've wondered about that. Unfortunately, my typical recharging power source is just a crummy old 15 amp house circuit. I think I'm stuck. 

@YanniLazarus, I'm not sure what specific model @AnOldUR has, but Victron (and probably others) make 30 amp chargers that plug into regular house circuits.

The 30 amp rating refers to the charging current, not the supply current. Since 30 amps at 12 volts is only 3 amps at 120 volts, you could go for that larger charger if you were so inclined.

Once again the T@B community super helps me out!   I am still using 2 6V AGM batteries in my 320 (230AH), but I'm thinking ahead to swapping out to lithium when it's time to buy new batteries. Unlike when I first got my AGMs, I can now get a built in battery heater and a single 300 AH lithium battery that will stand on end in my old small front tub.  Simple- simple.   It sounds like the factory wiring is adequate for my no- inverter 320, and I can switch to a faster charger if I want.  The (T@B) world is a good place...

rh5555

elbolillo said:

rh5555 said:

Just to be clear, in Victron's lithium setup with the Multiplus, where did they install the battery disconnect switch? Between the batteries and the Multiplus? Or between the battery/Multiplus group and the rest of the trailer?

Battery/multiplus group, and the rest of the trailer

So when the disconnect switch is turned off, you have no 12V power regardless of if you have shore power or not?  A distinct change from earlier wiring...

ScottG

elbolillo said:

rh5555 said:

Just to be clear, in Victron's lithium setup with the Multiplus, where did they install the battery disconnect switch? Between the batteries and the Multiplus? Or between the battery/Multiplus group and the rest of the trailer?

Battery/multiplus group, and the rest of the trailer

Hmm. Well that's interesting. If the battery disconnect is downstream from the Multiplus (which is also supported by recent photos of the factory install provided by @Hammick) than I wouldn't expect it to be carrying any more than 40A enroute to the distribution panel. This begs the question of why the disconnect switches in these models are inadequate and needed to be recalled.

I was operating on the assumption the disconnect was installed between the batteries and the Multiplus. That's how it's shown in this diagram of a 320 installation courtesy of @MuttonChops.

Now I'm back to wondering what I am missing here...

elbolillo

I have seen a couple of different photos of the NuCamp installation, and the wiring was different for each, so I cannot confirm exactly what they have been doing.

In talking to a technician at BattleBorn, he suggested that I have a battery switch between the Multiplus and the battery bank, so as to isolate the Multiplus. This is what I have done.

ScottG

Thanks, @elbolillo. Your location is what makes intuitive sense to me.

From where do you feed power to the 12VDC distribution panel? In @Hammick's photos there appears to be a smaller red wire exiting the Multiplus. In piecing things together as best I can, it looks like that might be a pass-through that runs to the disconnect and (presumably) on to the distribution panel. @MuttonChops' 320 diagram shows something similar. 

However, I don't see any other red wires coming out of your Multiplus.

And where to the 2/0 wires that snake out the hole in the lower left go?

elbolillo

ScottG said:

Thanks, @elbolillo. Your location is what makes intuitive sense to me.

From where do you feed power to the 12VDC distribution panel? In @Hammick's photos there appears to be a smaller red wire exiting the Multiplus. In piecing things together as best I can, it looks like that might be a pass-through that runs to the disconnect and (presumably) on to the distribution panel. @MuttonChops' 320 diagram shows something similar. 

However, I don't see any other red wires coming out of your Multiplus.

And where to the 2/0 wires that snake out the hole in the lower left go?

That disconnect switch only isolates the Multiplus from the batteries.

One 2/0 cable runs to a distribution block. The other comes back to the battery. Then from the distribution block, a cable runs to the main battery disconnect that connects to the 12v distribution panel.

elbolillo

@ScottG @rh5555

The Victron Multiplus inverter/charger doesn't provide DC power directly to your DC circuits as a converter charger does; it gives power to the battery, and the battery powers your DC circuits. If you disconnect your battery you will not have 12 VDC power even when on shore power with the Multiplus on, and if you turn the Multiplus off it will not pass AC power through to the AC circuits.