diy solar

diy solar

Can you offer advice on an expandable RV setup?

It’s 120VAC not 120VA/C
AC is sortofa acronym.
A technical colloquialism.

A/C is the accepted nomenclature for air conditioning.

Porsche is said two ways.
Jaguar is said two or three ways.
Haverhill is said mostly two ways.
Barre is said two ways.
Ariana is said several ways.
Is paraffin wax? Or kerosene?

Of course these days A/C could be identifying as electricity. That’s a bit shocking, current capacity aside.
Watt you do could be amping up a controversy. Ohm I gawd I better not open that circuit. I’ve hertz that can short circuit things. Need to stay grounded.
awesome! Thank you for the smile this morning :)
 
Well as usual I went ahead and jumped in the deep end. Ordered 2x EG4-LifePower4 Lithium Battery 12V 400AH on Saturday ands they arrived today. Extremely fast service, pretty impressed. Also it looks like I got an upgraded version of the battery. They have a built in interface and a Bluetooth id listed on each unit.

EG4-12v-400ah.jpg

EG4-12v-400ah-2.jpg

The only negative so far is I do not find a manual and the online manual does not match what I am seeing. Have sent an email inquiring about a download that is current.

Also got my shunt and various other parts in. Starting to get a bit scary being my first install. Will probably be asking lots more questions.
 
Well as usual I went ahead and jumped in the deep end. Ordered 2x EG4-LifePower4 Lithium Battery 12V 400AH on Saturday ands they arrived today. Extremely fast service, pretty impressed. Also it looks like I got an upgraded version of the battery. They have a built in interface and a Bluetooth id listed on each unit.

View attachment 133842

View attachment 133843

The only negative so far is I do not find a manual and the online manual does not match what I am seeing. Have sent an email inquiring about a download that is current.

Also got my shunt and various other parts in. Starting to get a bit scary being my first install. Will probably be asking lots more questions.
envy
 
Another piece of the puzzle came today. Also spent a bit of time and worked on layout for panels. Here is the latest piece.

MultiPlus2.jpg

Sucker is kind of heavy.

Used the drone ot get shot of the roof with a sample cardboard panel up there. My drone shot is not perfectly square but close enough for planning. Then copied the sample panel and placed it where I thought they would fit best. (Stole that idea from a Changing Lanes YouTube video.) Used Newpowa panels for the layout but am looking around to see what else is out there. With their 220 10bb panels (30.25" x 57") I would probably go with 8 or 9 of them. The string of 4 on the bottom right of image is a bit tight, so maybe 8. Would look similar to this.

Newpowa-220.jpg

If I used the 200 9bb's which are a bit narrower (27.76" x 55.28"), I could put 9 or 10 panels and still have room to move around.

Newpowa-200.jpg

Any words of wisdom or panel recommendations?
 
If you use the typical Z brackets to secure the panels to the roof, be aware that the Z brackets add 1" to 1.5" to the "footprint" of the panel. You don't want to get too close to the edge of the roof with the panel brackets.

Unistrut is a popular alternative way to secure the panels. It's my understanding that the brackets inserted into the Unistrut should attach to the long ends of the panels, two per side. In your case, if you laid the Unistrut rails parallel to the trailer length that would work. However, if you do that then should you decide later to use a wider (not longer) panel, the rails would not be in the right position. The "solution" to that is to add another layer of Unistrut perpendicular to the existing Unistrut, which would allow you to accommodate a wider or narrower panel.

I used Z brackets to install my panels. It was only two 320 watt panels, so not a big deal. Next time, I'll probably use Unistrut. The really nice thing about the Unistrut is that you can get it secured into every roof truss. Securing anything into just the roof subsurface (OSB/plywood/etc) isn't good enough. If you have a fiberglass or aluminum roof, adhesive can be good enough (no screws), but I'm not a fan of using just adhesive.

Depending on how you plan to configure the panels (series/parallel), odd numbers of panels don't work well. If you're going to created distinct strings associated with their own solar charge controller, then the number of panels on each string doesn't matter. Attempting to parallel strings with different numbers of series panels is not optimal.

10 panels could be more than 300 lbs of additional weight on the roof, not including mounting hardware and cabling. Something to keep in mind.
 
If you use the typical Z brackets to secure the panels to the roof, be aware that the Z brackets add 1" to 1.5" to the "footprint" of the panel. You don't want to get too close to the edge of the roof with the panel brackets.

Unistrut is a popular alternative way to secure the panels. It's my understanding that the brackets inserted into the Unistrut should attach to the long ends of the panels, two per side. In your case, if you laid the Unistrut rails parallel to the trailer length that would work. However, if you do that then should you decide later to use a wider (not longer) panel, the rails would not be in the right position. The "solution" to that is to add another layer of Unistrut perpendicular to the existing Unistrut, which would allow you to accommodate a wider or narrower panel.

I used Z brackets to install my panels. It was only two 320 watt panels, so not a big deal. Next time, I'll probably use Unistrut. The really nice thing about the Unistrut is that you can get it secured into every roof truss. Securing anything into just the roof subsurface (OSB/plywood/etc) isn't good enough. If you have a fiberglass or aluminum roof, adhesive can be good enough (no screws), but I'm not a fan of using just adhesive.

Depending on how you plan to configure the panels (series/parallel), odd numbers of panels don't work well. If you're going to created distinct strings associated with their own solar charge controller, then the number of panels on each string doesn't matter. Attempting to parallel strings with different numbers of series panels is not optimal.

10 panels could be more than 300 lbs of additional weight on the roof, not including mounting hardware and cabling. Something to keep in mind.

All good points. The width of panels is a bit of a concern, makes me lean toward the 200's. May consider the RICH Solar panels as they are an inch narrower. I do plan on using Unistrut for mounting unless something better shows up. I know you should never say never, but I do not anticipate upgrading to larger panels. Will for sure be screwing to the roof trusses.

Good point on the number of panels also. I am still in the research mode on MPPTs, they seem the most difficult part for me to get a grasp of.

Weight wise I have a max total of 800lbs additional weight as my target. Batteries add 100 of that, then all the other stuff and panels will eat at it pretty quickly. Another reason to consider the RICH panels I guess. I could go over that but then the wife would need to pack less.

Thanks for the response.
 
Look local for panels. Shipping panels has not been very successful. There are plenty of threads here about broken panels and lousy customer service getting them replaced. This is for just about any vendor. The challenge with picking up panels locally is that they'll all be residential and the larger format. But local sure beats the heck out of incurring shipping costs.

I had planned to install four 200 watt panels on my RV, but when I tried to come up with a plan for placing them there just wasn't room. So I switched to two larger panels. Fewer, larger panels means less install time. I used a CAD program to make sure the dimensions of everything were 100% right.
 
Push the panels all the way to the outer edge. You can see shadows from the aircon units, shadows are devastating to a panels output. With as many panels as you have, I'd look at a rail system. Carefully consider how they are going to be wired and the impact to the system. I don't have nearly as much usable roof space as you do, and divided my panels into three on drivers side and three on pass side and ran parallel connection wires to two SCC
 
Guess I got lucky, ordered 10 200w Rich solar panels from Amazon and all 10 came in great shape, no damage at all. All my other parts are here so now just have to find time to work on it.
 
Okay, I'm back with some questions. Ended up with a big work project and no time to work on this project. At least it helps pay for the goodies.

Below is an image of what I am planning for my first step of the install. Basically to get the batteries in place and the Multiplus II in place so I can charge the batteries and start to make use of some of the equipment until I have time to mount my panels.

Couple of questions:
  1. I went ahead and purchased a Lynx Power In 1000
    1. location for it, my thought is on the positive side it would go between the batteries and the fuse, on the negative between the batteries and the smart shunt
    2. do the cables need to be the same length from both batteries to the Lynx Power In?
  2. On the ground to frame from the smart shunt do both cables just attach to the smart shunt?
  3. The ground to frame wire for the Multiplus II, the ground to frame on the current inverter is a bare copper and pretty small, is that sufficient or do I need a heavy wire there?
  4. See any issues with my plan?
Sorry for the big time delay on this but work is income and it comes first.

Also, I got 2 MPPT 100/70s for between the panels and batteries when I get to that.

1st-step-50-amp.jpg
 
Battery -> fuse -> switch -> Lynx Power In

If you have the Lynx Distributor, the output of the MPPT would go to the Lynx Distributor.

Look at the battery wiring configurations in the Wiring Unlimited document found in the Resources section of the forum.


If you use a set of common bus bars (or the Lynx Distributor), your connection to the chassis frame would come off of that. Don't stack too much on the shunt. The only stacked items on my shunt were the cables from the two batteries.

Instead of the RV Load Disconnect switch, consider using a BatteryProtect 65 Smart. It will keep devices on the RV's 12 circuit from draining your LiFePO4 battery bank too far. It can also function as a switch using VictronConnect. That came in handy one night when my CO detector went bad (it really was bad). I shut the CO detector off for sure by cutting off the entire 12 volt feed.
 
I do not have the Distributor, just the Power In. I found the below on the Victron website. It shows it connect similar to what I was thinking. Basically it is just a bus bar.

In looking at this diagram it would appear that I could run the cables from t he batteries to the Power In for the positive and then run the negative cables to the shunt then to the Power In from the smart shunt. That would have the two battery cables on the negative attached to the smart shunt and then one cable running to the Power In. All other negatives would be attached to the Power In or to a negative bus bar attached to the Power In.

My batteries are smart batteries with BMS and breakers on the front. Do I still need the fuse between the battery and the Power In? Seems redundant.

lynx-power-in-1000.png
 
The Lynx Power In is basically a set of bus bars, like you said.

The diagram above shows the cables from the battery going into "ports" on the Lynx that would have a fuse on it. But they still show a fuse on the cable. The fuse protects the wire. So yes, you still need the fuse.
 
Okay, don't take this as me being obnoxious, just trying to understand. Each battery has a breaker and the BMS which the manual says will prevent anything over 200amp draw. So if I put a 200 amp fuse between the battery and the bus bar is that not already protected by the BMS and breaker? I just thought it would work like a house breaker which trips when overloaded or shorted.
 
Okay, don't take this as me being obnoxious, just trying to understand. Each battery has a breaker and the BMS which the manual says will prevent anything over 200amp draw. So if I put a 200 amp fuse between the battery and the bus bar is that not already protected by the BMS and breaker? I just thought it would work like a house breaker which trips when overloaded or shorted.
I'm leery of breakers in high amp DC circuits. I've worked on enough 12V and 24V DC systems over the years and can say circuit breakers may not always trip when needed or arced inside and welded shut leading to serious problems if there wasn't fuse protection farther up the line.

I built my battery bank with fuses right at the batteries, one T fuse per battery. No breakers. After the busbar joining the batteries together in parallel, I have one large ABB breaker with a shunt trip and controlled by the Batrium. This is an industrial breaker, rated to 600V DC.
 
I'm leery of breakers in high amp DC circuits. I've worked on enough 12V and 24V DC systems over the years and can say circuit breakers may not always trip when needed or arced inside and welded shut leading to serious problems if there wasn't fuse protection farther up the line.

I built my battery bank with fuses right at the batteries, one T fuse per battery. No breakers. After the busbar joining the batteries together in parallel, I have one large ABB breaker with a shunt trip and controlled by the Batrium. This is an industrial breaker, rated to 600V DC.
That makes sense. I have not worked with high amperage DC until now, hence the questions.

So sounds like you would recommend a T fuse. The batteries have a max discharge of 200 amps, so would you use a 200 amp T fuse?

Or what about somethign like this: https://www.amazon.com/Blue-Sea-Systems-5191-Terminal/dp/B0019ZBTV4/
 
When we put over current protection in place, we size it to 1.25 times the expected continuous current to avoid nuisance trips. If you expect to pull 200 amps then a 250 amp fuse is appropriate.

I have two 280 Ah batteries, each with a 120 amp BMS. I've been running a 225 amp Class T fuse for the past two years with no problem. Based on my loads, I would not come close to 200 amp continuous discharge/charge. But just in case, I have a higher amp fuse as a backup.

I do use an MRBF 30 amp fuse in my system, but it's on the circuit to my RV's main distribution panel, which shouldn't ever see more than about 20 amps of load. The Class T fuse is better for using on the battery main circuit. It has a higher AIC rating that the MRBF.

Class T fuses are expensive and can be hard to find in stock. The MRBF is less expensive and tends to more likely be in stock . There is a rumor that the AYBC is going to allow an MRBF in their guidelines. I'll stick with my Class T.
 
That makes sense. I have not worked with high amperage DC until now, hence the questions.

So sounds like you would recommend a T fuse. The batteries have a max discharge of 200 amps, so would you use a 200 amp T fuse?

Or what about somethign like this: https://www.amazon.com/Blue-Sea-Systems-5191-Terminal/dp/B0019ZBTV4/
I run a 175A T fuse on each battery. Shown here in my battery bank build. https://diysolarforum.com/threads/the-big-blue-box.55099/

I see you have the EG4 batteries. They claim a fuse isn't needed, I guess the choice is yours regarding fusing at the batteries.

I see a T fuse before the inverter, that is good.
 
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