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ambo wanderer build

wasteland wanderer

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Apr 29, 2022
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I have a 1998 freightliner retired ambulance that im converting to an overlanded camper build i decided i want to go with a

EG4 6.5kW Off-Grid Inverter | 6500EX-48 | 6500W Output | 8000W PV Input | 500V VOC Input | UL 1741 Certified | All in One Solar Inverter and x2​

EG4-LifePower4 Lithium Battery | 48V 100AH | Server Rack Battery | UL 1973 Listed.​

Currently looking at this solar panel but am unsure if it will be the perfect fit and compatible with my system which lies my question, will this work good with this system setup? solar panels

what I'm trying to accomplish is max watt per panel with a per panel dimension around 40x 80.​

Also would like a constant 4 panel hookup with a simple plug and go ground system, aka extra panels I carry around. Is this possible and how would i go around doing this?​

For me paint works very well so i made a little diagram of how i think i can get this to work, just need some guidance.​

I also am unsure of steping down 48v to 12v system but i was told this​

Powermax WFCO WF8955PECB Black 55A Replacement Power Center (PPC 55A) would work. or is there somthing similar but better?​

eventually I may want to add another 2 batteries but the connectors would be different lengths as the first 2 batteries will this be an issue?​


I also will eventually be wanting to set up alternator charging. To my knowledge i need a dc to dc charge and make sure alternator is big enough. i plan to do a separate alternator all together just for these batteries. Any link to a dc to dc charger and how to hook this up to this system would be great.​

I am an information sponge and am ready to buy ASAP b4 things start to become hard to find.​

 

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Currently looking at this solar panel but am unsure if it will be the perfect fit and compatible with my system which lies my question, will this work good with this system setup? solar panels

Best way is to have seperate charge controllers for each array. This is very common on sailing boats because of awkward deck shapes and shading issues

eventually I may want to add another 2 batteries but the connectors would be different lengths as the first 2 batteries will this be an issue?
Yep it could create an issue due to different resistances between batteries. The devil is always in the detail

For a mobile set up there does seem to be a lot of power there. What are you planning to run off it?

Also why is the whole post in bold?
 
Best way is to have seperate charge controllers for each array. This is very common on sailing boats because of awkward deck shapes and shading issues


Yep it could create an issue due to different resistances between batteries. The devil is always in the detail

For a mobile set up there does seem to be a lot of power there. What are you planning to run off it?

Also why is the whole post in bold?
sorry because i did a copy and paste from another part of the forum where nobody commented for 2 weeks thats why its bold. I plan to be a mobile carpentry workshop eventually with a pull behind trailer. 2 fridges and i plan to even have a washing machine. batteries id imagine its an easy fix just make all wiring approximately the same length. for solar any way to get around having to run x2 charge controllers? i thought thats what combiner boxes were for? thank you for your speedy post and help.
 
I see in another post you want to run possibly saws and other motors. You might need more than 2 batteries.

Currently looking at this solar panel but am unsure if it will be the perfect fit and compatible with my system which lies my question, will this work good with this system setup? solar panels


Bifacial on a RV would not be a good choice. I run a string of 8 530W into just one SCC of the EG4 6500EX and that will maximize out the input for one SCC. Those 530W panels are big though, 45 inches by 7.5 feet.

The trick with any SCC is to look at the VOC rating of the panel and see how many you can put in series to stay under 500VOC in cold weather. Something like this 455W from San Tan with 8 in series. https://www.santansolar.com/product/new-solarever-455w-solar-panel/

However, I doubt you need to worry about installing 8 panels on your roof real estate of the ambulance. What are the roof dimensions?

what I'm trying to accomplish is max watt per panel with a per panel dimension around 40x 80.​


Beware of bifacial, I doubt it will work.

Also would like a constant 4 panel hookup with a simple plug and go ground system, aka extra panels I carry around. Is this possible and how would i go around doing this?​


If you intend to move panels around, you want something smaller as the larger the panel, the heavier they get. The 455W I linked is 52 lbs and bulky.

For me paint works very well so i made a little diagram of how i think i can get this to work, just need some guidance.​

I also am unsure of steping down 48v to 12v system but i was told this​

Powermax WFCO WF8955PECB Black 55A Replacement Power Center (PPC 55A) would work. or is there somthing similar but better?​


Just a simple buck converter is what you need. Running an inverter to generate ac power and converting it back to to DC is wasteful and inefficient. I use a simple buck converter to go from 24V to 12V. https://www.amazon.com/gp/product/B07QXV8V2L/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1 For the Chinese stuff, figure double the watts you would need to size it. Mine is 720W which is 60A for 12V. Way more than I would ever need.

eventually I may want to add another 2 batteries but the connectors would be different lengths as the first 2 batteries will this be an issue?​


It can be if the length is excessive. Best practice is stacking with busbars between batteries.

I also will eventually be wanting to set up alternator charging. To my knowledge i need a dc to dc charge and make sure alternator is big enough. i plan to do a separate alternator all together just for these batteries. Any link to a dc to dc charger and how to hook this up to this system would be great.​

I am an information sponge and am ready to buy ASAP b4 things start to become hard to find.​

 
sorry because i did a copy and paste from another part of the forum where nobody commented for 2 weeks thats why its bold. I plan to be a mobile carpentry workshop eventually with a pull behind trailer. 2 fridges and i plan to even have a washing machine. batteries id imagine its an easy fix just make all wiring approximately the same length. for solar any way to get around having to run x2 charge controllers? i thought thats what combiner boxes were for? thank you for your speedy post and help.
With both panels and batteries everything needs to be nicely balanced

Panels - as mentioned above you’ve specced big panels that will be tough & heavy to move around. For a temporary ground mounted array light flexible panels work well

A much more flexible solution is to have seperate charge controllers specced for each array

Batteries are better if they are very closely matched for internal resistance. Adding batteries at a later date brings challenges for this. The simple reliable solution is to install new same spec batteries that have been too balanced together at the same time. Anything else brings complications that can result in poor reliability especially if you are going to push them
 
I see in another post you want to run possibly saws and other motors. You might need more than 2 batteries.


Bifacial on a RV would not be a good choice. I run a string of 8 530W into just one SCC of the EG4 6500EX and that will maximize out the input for one SCC. Those 530W panels are big though, 45 inches by 7.5 feet.

The trick with any SCC is to look at the VOC rating of the panel and see how many you can put in series to stay under 500VOC in cold weather. Something like this 455W from San Tan with 8 in series. https://www.santansolar.com/product/new-solarever-455w-solar-panel/

However, I doubt you need to worry about installing 8 panels on your roof real estate of the ambulance. What are the roof dimensions?



Beware of bifacial, I doubt it will work.


If you intend to move panels around, you want something smaller as the larger the panel, the heavier they get. The 455W I linked is 52 lbs and bulky.



Just a simple buck converter is what you need. Running an inverter to generate ac power and converting it back to to DC is wasteful and inefficient. I use a simple buck converter to go from 24V to 12V. https://www.amazon.com/gp/product/B07QXV8V2L/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1 For the Chinese stuff, figure double the watts you would need to size it. Mine is 720W which is 60A for 12V. Way more than I would ever need.



It can be if the length is excessive. Best practice is stacking with busbars between batteries.
thank you sir, what is the term SCC? sorry just woke up brain not clicking. i plan to go 4 max panels on roof they will 2 panels on roof with the other 2 on slides that will slide out while parked. other half of roof i plan to have a deck or rooftop tent. copy stay away from bifacial. im guessing cracks easy? for buck converter 48v to 12v, when sizing the watts that would the minimal watts i would output at 12v correct so say ill have 15 watt at 12v so get a 20 watt buck converter to be safe? for the batteries the length would be no more the 4 ft of wire per battery.
 
With both panels and batteries everything needs to be nicely balanced

Panels - as mentioned above you’ve specced big panels that will be tough & heavy to move around. For a temporary ground mounted array light flexible panels work well

A much more flexible solution is to have seperate charge controllers specced for each array

Batteries are better if they are very closely matched for internal resistance. Adding batteries at a later date brings challenges for this. The simple reliable solution is to install new same spec batteries that have been too balanced together at the same time. Anything else brings complications that can result in poor reliability especially if you are going to push them
thank you sir i think ill just leave room in my system for upgrades in batteries and panels for a later date
 
thank you sir, what is the term SCC? sorry just woke up brain not clicking. i plan to go 4 max panels on roof they will 2 panels on roof with the other 2 on slides that will slide out while parked. other half of roof i plan to have a deck or rooftop tent. copy stay away from bifacial. im guessing cracks easy?

In order for bifacial to work, it needs to have light come from the backside. On a RV roof, it might have some reflective ability but the issue is everything has to be sized for the max output even if the backside doesn't yield anything most days.

You will find in winter time, flat mounted panels will have a reduced yield. The slide is a good feature, to install more panels than roof space. Portable panels with their own SCC (solar charge controller) will help in winter.

for buck converter 48v to 12v, when sizing the watts that would the minimal watts i would output at 12v correct so say ill have 15 watt at 12v so get a 20 watt buck converter to be safe?

For a 12V 15W draw, I'd prefer a 30W buck converter for the example. Twice the size, derate the Chinese stuff by 50%. You will have to determine how many watts you need. On my truck camper, I have a Dometic CFX95 fridge/freezer in the back seat of the cab, this is powered thru the converter in the truck camper so it runs off solar and not the truck electrical system. I have other 12V items such as water pump, fans etc. As my converter is 720W, I can have a load with the derate of 50% of 30A on 12V, 360W.

for the batteries the length would be no more the 4 ft of wire per battery.
The way I would do it is have a central point midway with a busbar between the 2 banks, keep all cables from each battery the same length. All negatives go to one busbar, the positives the same. With the cables all the same length, the resistance of each battery circuit is the same.
 
In order for bifacial to work, it needs to have light come from the backside. On a RV roof, it might have some reflective ability but the issue is everything has to be sized for the max output even if the backside doesn't yield anything most days.

You will find in winter time, flat mounted panels will have a reduced yield. The slide is a good feature, to install more panels than roof space. Portable panels with their own SCC (solar charge controller) will help in winter.



For a 12V 15W draw, I'd prefer a 30W buck converter for the example. Twice the size, derate the Chinese stuff by 50%. You will have to determine how many watts you need. On my truck camper, I have a Dometic CFX95 fridge/freezer in the back seat of the cab, this is powered thru the converter in the truck camper so it runs off solar and not the truck electrical system. I have other 12V items such as water pump, fans etc. As my converter is 720W, I can have a load with the derate of 50% of 30A on 12V, 360W.


The way I would do it is have a central point midway with a busbar between the 2 banks, keep all cables from each battery the same length. All negatives go to one busbar, the positives the same. With the cables all the same length, the resistance of each battery circuit is the same.
Ok i know see what your saying it makes since. I dont need a whole other. Inverter for the ground deploy solar just a charge controler that also feeds... straight to batteries or inverter?

Battery set up got you on that part too, very simple fix up.

Buck converter wires straight into inverter or a panel box? Then down end of buck converter would be a fuze box correct?

I feel like i know a little bit just not alot a bit lol
 
Ok i know see what your saying it makes since. I dont need a whole other. Inverter for the ground deploy solar just a charge controler that also feeds... straight to batteries or inverter?

Charge controller to DC bus for batteries. Install busbars now for the connection point for future expansion of battery bank. The SCC should go to that point.

Battery set up got you on that part too, very simple fix up.
(y)
Buck converter wires straight into inverter or a panel box? Then down end of buck converter would be a fuze box correct?
Buck converter needs to be fused either with a breaker or fuse rated for max input of the buck converter. An example on my truck camper converter, it is 720W (60A) output on 12V. Input on 24V is 30A. So I need a 30A breaker or fuse for the input of the converter. I used a breaker so I can turn off the converter for storage purposes as there will be a small draw all the time from the converter. If it was frequent that I would turn it off, I would use a switch.

I feel like i know a little bit just not alot a bit lol
Read threads like this to get an idea of what to do. https://diysolarforum.com/threads/heres-my-truck-camper-setup.29488/
 
Charge controller to DC bus for batteries. Install busbars now for the connection point for future expansion of battery bank. The SCC should go to that point.


(y)

Buck converter needs to be fused either with a breaker or fuse rated for max input of the buck converter. An example on my truck camper converter, it is 720W (60A) output on 12V. Input on 24V is 30A. So I need a 30A breaker or fuse for the input of the converter. I used a breaker so I can turn off the converter for storage purposes as there will be a small draw all the time from the converter. If it was frequent that I would turn it off, I would use a switch.


Read threads like this to get an idea of what to do. https://diysolarforum.com/threads/heres-my-truck-camper-setup.29488/
thanks man this helped me out alot.
 
Charge controller to DC bus for batteries. Install busbars now for the connection point for future expansion of battery bank. The SCC should go to that point.


(y)

Buck converter needs to be fused either with a breaker or fuse rated for max input of the buck converter. An example on my truck camper converter, it is 720W (60A) output on 12V. Input on 24V is 30A. So I need a 30A breaker or fuse for the input of the converter. I used a breaker so I can turn off the converter for storage purposes as there will be a small draw all the time from the converter. If it was frequent that I would turn it off, I would use a switch.


Read threads like this to get an idea of what to do. https://diysolarforum.com/threads/heres-my-truck-camper-setup.29488/
Someone mentioned to me about using a buck converter that some appliances may have issues regaurding it being 12v nominal not actually 12v. Can you give me some input?
 
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