Questions about truck camper setup

[GoldCountryCA]

I bought a truck camper that will be here in May. In the meantime, I’m buying things to go into/onto the camper; currently working on the solar setup.

Renogy was having a sale so I bought the 50a dc-to-dc charger/mppt and their 2000w inverter charger. I also ordered four 100w Renogy black flexible “lightweight” solar panels as they were on sale on the jungle website. I haven’t made up my mind on batteries yet, as I have questions.

1. I imagine the leads from the solar panels are easy enough to shorten for a clean install on the roof? I don’t want slack or loops. Also, I thought about 200w on the roof and 200w on a kickstand, but I’m concerned about theft. Anyone have their panels stolen?

2. I looked up the 400w setup detailed here:

RV Solar Power Blue Prints

Building a vehicle mounted solar power system? Let me help.

www.mobile-solarpower.com

On this setup, he’s called out 200ah worth of lithium battery. However, since I plan on camping in the PNW quite often in areas with a thick tree canopy, I’m leaning towards more towards 3-400ah. I was looking at two ampere time 200ah with 200a BMS, or at four ampere time 100ah with 100a BMS. The reasons for considering four 100ah batteries vs the two 200ah are:

a) they will be a more efficient use of space in the cabinet they’ll be located in.

b) if something goes wrong on one battery, it’ll be much cheaper to replace and less detrimental during the period it’s down.

Will there be any performance differences with these two arrangements?

3. Has anyone come across a 4 circuit AC load center smaller than this:

Square D Homeline 70 Amp 2-Space 4-Circuit Indoor Flush Mount Main Lug Load Center with Cover HOM24L70FCP - The Home Depot

The Square D Homeline 70 Amp 2-Space 4-Circuit Indoor Surface Mount Main Lugs Load Center is UL listed for residential and commercial power distribution. This load center is built with a plated, aluminum

www.homedepot.com

I’d like to have a separate circuit leading to shore power lead, line side of inverter, load side of inverter and ac outlets.

The pro to this setup are to be able to bypass the need for the inverter to power ac circuit while hooked to shore power. I was thinking that if I’m hooked to shore power, no need in running high amp loads through the inverter (we’ll potentially be bringing a portable AC unit for trips to hot areas for the dogs).

The con to this setup is that my wife or someone else may potentially energize the load side of the inverter with shore power, potentially causing damage (either the shore power breaker will be providing power to the bus bar or the load side of the inverter will, but both breakers should not be on at the same time to prevent backfeeding).

Perhaps I can find an ‘A or B’ switch to tie both the load side of the Inverter and the shore plug into a single breaker, effectively fool proofing the system. But such a switch would need to be rated accordingly.

Any thoughts or criticisms to my plan would be greatly appreciated!

 

[time2roll]

As long as the inverter-charger has been purchased I would plan on powering the entire panel full time and skip the sub panel.
Set the fridge and water to propane only and disable the converter and all should be fine. I assume no A/C option if considering a portable.

I recommend slowing down on more purchase decisions until the TC is delivered. Easier measure fitment and connection logistics.

 

[GoldCountryCA]

As long as the inverter-charger has been purchased I would plan on powering the entire panel full time and skip the sub panel.
Set the fridge and water to propane only and disable the converter and all should be fine. I assume no A/C option if considering a portable.

I recommend slowing down on more purchase decisions until the TC is delivered. Easier measure fitment and connection logistics.

Fridge is an iceco 12v dc. Water heater will be diesel and I’m planning on doing hydronic heat with that. The camper is an empty shell and I’m building the entire thing out to maximize space, but I get what you are saying by pumping the brakes on purchases. I’ve been 3d modeling the components to determine fit and location.

No integrated air conditioning as of now. I considered a Dometic RTX, but I’m not a fan of how big it is. Don’t want stuff on the roof that can catch on branches or increase my COG. I may build a small air conditioning system into an external box (I’m pulling the truck bed, building a flatbed with a floor at the same height as my factory bed and building the bed sides out of tool boxes), but I need to find a decent stand alone 12v variable speed compressor. I could always buy an RTX and tear it apart to alter the form.

My concern with having the inverter charger doing double duty charging the house batts, running 12v power and powering an AC air conditioning unit all through the AC terminals on the renogy unit only designed to be a 2000w inverter. I’m not sure of the sizing on the conductors inside the unit. The tech at renogy couldn’t say what the inner wire size is. I’m thinking about heat and taxing the unit…

 

[time2roll]

12vdc fridges are great.... Good to have nothing on the roof to max out the solar. I think 400+w on the roof would be fully utilized.

 

[GoldCountryCA]

As long as the inverter-charger has been purchased I would plan on powering the entire panel full time and skip the sub panel.
Set the fridge and water to propane only and disable the converter and all should be fine. I assume no A/C option if considering a portable.

I recommend slowing down on more purchase decisions until the TC is delivered. Easier measure fitment and connection logistics.

Fridge is an iceco 12v dc. Water heater will be diesel and I’m planning on doing hydronic heat with that. The camper is an empty shell and I’m building the entire thing out to maximize space, but I get what you are saying by pumping the brakes on purchases. I’ve been 3d modeling the components to determine fit and location.

No integrated air conditioning as of now. I considered a Dometic RTX, but I’m not a fan of how big it is. Don’t want stuff on the roof that can catch on branches or increase my COG. I may build a small air conditioning system into an external box (I’m pulling the truck bed, building a flatbed with a floor at the same height as my factory bed and building the bed sides out of tool boxes), but I need to find a decent stand alone 12v variable speed compressor. I could always buy an RTX and tear it apart to alter the form.

My concern with having the inverter charger doing double duty charging the house batts, running 12v power and powering an AC air conditioning unit all through the AC terminals on the renogy unit only designed to be a 2000w inverter. I’m not sure of the sizing on the conductors inside the unit. The tech at renogy couldn’t say what the inner wire size is. I’m thinking about heat and taxing the unit…

 

[GoldCountryCA]

12vdc fridges are great.... Good to have nothing on the roof to max out the solar. I think 400+w on the roof would be fully utilized.

I agree. We have a 1 year old rv with all the goodies that we could take if visiting the hotter climates/SW. Some places are inaccessible with it due to size though, hence the truck camper build.

I believe the RTX pulls 19a in eco mode. So in theory, the 4800 wh should be able to maintain taking the edge off for the hotter hours of the day.

 

[JBennettBus]

1. I imagine the leads from the solar panels are easy enough to shorten for a clean install on the roof?

Pretty much. I accidentally broke a connector on a panel lead recently. Just clipped it, stripped, and crimped on a new one. Same process for shortening a lead on purpose.

...I’m concerned about theft. Anyone have their panels stolen?

I don't think that would be problem unless you leave the portable panels unattended for a long time. Depends on the area of course. The places I camp, there are usually too many people around for thieves to operate, or I'm so isolated I can see them coming from a long ways off.

...since I plan on camping in the PNW quite often in areas with a thick tree canopy, I’m leaning towards more towards 3-400ah.

I just installed a 300AH LifePo4 for pretty much the same reason. Probably more storage than I need, but it will help get through shady/cloudy times. I think the idea of multiple batteries is good. I went with a single battery mainly because I'd have had to extend my battery shelf a bit to accommodate them, and I didn't want to lose the floor space.

 

[GoldCountryCA]

I think I have a simple solution. I’ll use a single pole double throw switch, such as this 30a Leviton:


Pole one will be wired to the load side (AC output) of the inverter.

Pole two will be wired to the line side (AC input) of the inverter and the shore plug wiring.

The line terminal of the switch (acting as the load) will go to the camper 120v circuit.



This way, when hooked to shore power, shore line voltage will go directly to the 120v circuits and inverter output will not be utilized. It will only act as a charger.

 

[GoldCountryCA]

I don't think that would be problem unless you leave the portable panels unattended for a long time. Depends on the area of course. The places I camp, there are usually too many people around for thieves to operate, or I'm so isolated I can see them coming from a long ways off.

We plan on being gone for 5 or so hours at a time on mountain bike rides or something similar. Plenty of time to snag some panels. I guess worst case scenario, they’re making off with less than $300 worth of gear. But still…

 

[JBennettBus]

We plan on being gone for 5 or so hours at a time on mountain bike rides or something similar. Plenty of time to snag some panels.

It's a tricky decision. Fixed panels might be harder to steal, but the portable ones let you harvest more sun. I guess one way of looking at it is that you'll probably have a lot of days where they're useful and only one day when they get stolen, so maybe the risk isn't too bad.

The only thing I've had stolen so far was a small tire inflator. Some guy borrowed it. I looked out a couple of hours later to see if he had finished inflating the tire, and I guess he had because he was gone.

 

[Zwy]

I bought a truck camper that will be here in May. In the meantime, I’m buying things to go into/onto the camper; currently working on the solar setup.

Here was my build, still some changes coming.

Here's my truck camper setup

First photo is general view of components. Positive and negative busbars. 200a breaker goes to inverter, ANL fuse to fuse panel and 40a breaker on far left is for the buck converter. As this is a 24v system, I was able to use lighter cable as it was quite tight with tight bends in various...

diysolarforum.com

Renogy was having a sale so I bought the 50a dc-to-dc charger/mppt and their 2000w inverter charger. I also ordered four 100w Renogy black flexible “lightweight” solar panels as they were on sale on the jungle website. I haven’t made up my mind on batteries yet, as I have questions.

1. I imagine the leads from the solar panels are easy enough to shorten for a clean install on the roof? I don’t want slack or loops. Also, I thought about 200w on the roof and 200w on a kickstand, but I’m concerned about theft. Anyone have their panels stolen?

I cut the MC4 connectors off, used crimp splices with double heat shrink. Wires run from panels to a combiner box, I have 2S3P currently and will eventually go to 2S4P when the roof air is gone. From combiner box it runs thru the fridge roof vent down thru a wall and to the Growatt. It required pulling the fridge which I had other mods to do.

2. I looked up the 400w setup detailed here:

RV Solar Power Blue Prints

Building a vehicle mounted solar power system? Let me help.

www.mobile-solarpower.com

On this setup, he’s called out 200ah worth of lithium battery. However, since I plan on camping in the PNW quite often in areas with a thick tree canopy, I’m leaning towards more towards 3-400ah. I was looking at two ampere time 200ah with 200a BMS, or at four ampere time 100ah with 100a BMS. The reasons for considering four 100ah batteries vs the two 200ah are:

a) they will be a more efficient use of space in the cabinet they’ll be located in.

b) if something goes wrong on one battery, it’ll be much cheaper to replace and less detrimental during the period it’s down.

I have 24V 280Ah and it is sufficient, I plan on running a mini split (outside mount is done, need to do some cabinet work inside). Biggest problem is recharging due to days of bad weather and limited roof space for solar panels.

Will there be any performance differences with these two arrangements?

3. Has anyone come across a 4 circuit AC load center smaller than this:

Square D Homeline 70 Amp 2-Space 4-Circuit Indoor Flush Mount Main Lug Load Center with Cover HOM24L70FCP - The Home Depot

The Square D Homeline 70 Amp 2-Space 4-Circuit Indoor Surface Mount Main Lugs Load Center is UL listed for residential and commercial power distribution. This load center is built with a plated, aluminum

www.homedepot.com

View attachment 129816

I’d like to have a separate circuit leading to shore power lead, line side of inverter, load side of inverter and ac outlets.

The pro to this setup are to be able to bypass the need for the inverter to power ac circuit while hooked to shore power. I was thinking that if I’m hooked to shore power, no need in running high amp loads through the inverter (we’ll potentially be bringing a portable AC unit for trips to hot areas for the dogs).

The con to this setup is that my wife or someone else may potentially energize the load side of the inverter with shore power, potentially causing damage (either the shore power breaker will be providing power to the bus bar or the load side of the inverter will, but both breakers should not be on at the same time to prevent backfeeding).

Perhaps I can find an ‘A or B’ switch to tie both the load side of the Inverter and the shore plug into a single breaker, effectively fool proofing the system. But such a switch would need to be rated accordingly.

Any thoughts or criticisms to my plan would be greatly appreciated!

I'd opt for a transfer switch, that was part of the reason I purchased the Growatt, the transfer switch was built in. It will charge the battery with the inverter off, both off solar or shore power.

I have seen some use the rotary style switch. Similar to something like this https://www.amazon.com/Rotary-Posit...lja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1 that was properly rated. This ensures that power can not be from two sources at once.

 

[GoldCountryCA]

I’ve been doing a lot of thinking and I am ever so close to pulling the trigger on the battery portion of my setup and here’s where I’m at:

I don’t need low temp protection. My batteries will be in the conditioned space of the camper. As an additional safeguard, I can use a temp sensor of a thermostat switch in the battery compartment. That switch can be used as signal voltage to open and close a relay inline of the charging circuit from the dc to dc / mppt unit. Does this sound problematic?

This makes it very difficult to pay the premium for a battery such as an SOK, when I can get a Chins or Amperetime for roughly 60% of the SOK. Will has already demonstrated that these cheaper batteries have good cells, however doesn’t like the lack of low temp protection. Am I missing something?

Then I push that cost per Wh rational a step further. Why not buy individual cells on Amazon or eBay and build my own bank?
-The obvious upsides to this would be a much more flexible form factor, greater serviceability with individual cells and a price advantage over Chins and the like.
-the obvious downsides would be more wiring, protecting more wiring, less guarantee that I’m getting grade A cells and little to no warranty.

Which brings me to another question, if you don’t think my logic is flawed up to this point. Are there any sellers on Amazon or eBay that have a reputation for delivering what they are advertising?

 

[JBennettBus]

I don’t need low temp protection. My batteries will be in the conditioned space of the camper. As an additional safeguard, I can use a temp sensor of a thermostat switch in the battery compartment...

Then I push that cost per Wh rational a step further. Why not buy individual cells on Amazon or eBay and build my own bank?.

If you decide to build your own battery, you could skip the thermostat/relay and just use a BMS that has low-temp cutoff built-in. As for the benefits of rolling your own battery, I see it as similar to computers. Buying something off the shelf is simpler and will probably work, but building your own system gives you a lot more control. I bought a Li Time battery just for the simplicity, but I kinda sorta wish I'd DIY'd a battery instead.

 

[Zwy]

I’ve been doing a lot of thinking and I am ever so close to pulling the trigger on the battery portion of my setup and here’s where I’m at:

I don’t need low temp protection. My batteries will be in the conditioned space of the camper. As an additional safeguard, I can use a temp sensor of a thermostat switch in the battery compartment. That switch can be used as signal voltage to open and close a relay inline of the charging circuit from the dc to dc / mppt unit. Does this sound problematic?

This makes it very difficult to pay the premium for a battery such as an SOK, when I can get a Chins or Amperetime for roughly 60% of the SOK. Will has already demonstrated that these cheaper batteries have good cells, however doesn’t like the lack of low temp protection. Am I missing something?

You can always build a battery tray with a heating pad under it. My 24V battery in my truck camper has heating pad under the aluminum floor. I never wired in the thermostat for it yet, it's all here just other projects. If was planning on using the truck camper during winter, I'd wire it all up in short order.

You can use a Chins or Ampere and use a heating pad under a tray.

Then I push that cost per Wh rational a step further. Why not buy individual cells on Amazon or eBay and build my own bank?
-The obvious upsides to this would be a much more flexible form factor, greater serviceability with individual cells and a price advantage over Chins and the like.
-the obvious downsides would be more wiring, protecting more wiring, less guarantee that I’m getting grade A cells and little to no warranty.

Which brings me to another question, if you don’t think my logic is flawed up to this point. Are there any sellers on Amazon or eBay that have a reputation for delivering what they are advertising?

You can have a bigger battery (both voltage and Ah capacity) building your own for the same money. It does take time.

 

[GoldCountryCA]

One thing not pencilling out for me. If say, I go with a 300ah chins or ampertime with a 200a bms and I hook it to a 2000w 12v inverter that peaks at 4000w. For whatever reason, the stars align and I hit peak while the wife is using a hot plate and I'm outside using a power tool and every DC load is on; 4000w/12v=333a. How does the BMS handle this situation? I planned on between 2/0 and 4/0 from battery to inverter.

Another question: say for packaging purposes three 100ah batteries with 100a BMS on each battery works better for the space they are going, will this exacerbate or help the above stated scenario?

 

[Zwy]

One thing not pencilling out for me. If say, I go with a 300ah chins or ampertime with a 200a bms and I hook it to a 2000w 12v inverter that peaks at 4000w. For whatever reason, the stars align and I hit peak while the wife is using a hot plate and I'm outside using a power tool and every DC load is on; 4000w/12v=333a.

Unless it is low frequency inverter, it will most likely shut down in a few microseconds.

How does the BMS handle this situation?

It would depend on the C rating of the battery and the discharge rating of the BMS.

I planned on between 2/0 and 4/0 from battery to inverter.

If the system is changed to 24V, it would flow one half the amps of 12V. I've never quite understood why people want an inverter larger than 1500W and run it on 12V.

Another question: say for packaging purposes three 100ah batteries with 100a BMS on each battery works better for the space they are going, will this exacerbate or help the above stated scenario?

In parallel, the bms's will most likely shut down.

This is why it is sometimes advantageous to DIY a battery, it can fit in a spot and it can be customized to the needs.

 

[GoldCountryCA]

If the system is changed to 24V, it would flow one half the amps of 12V. I've never quite understood why people want an inverter larger than 1500W and run it on 12V.

It came down to availability of the systems I want to run and the cost of those systems in 12v vs 24v. It’s possible I could’ve made it all happen for around the same price.

In all likelihood, an induction cooktop is the only significant AC load I’ll ever have on the system.