How should I arrange my solar array? Will Prowse 48v mobile power system

[MbeBeefy]

I’m a newbie building an ambulance conversion. The 48v system allows me to scale up once I’m done with the ambulance and want to get land. I have the EG4 3000 inverter and the 48V 100-E battery from Trophy Battery. On the roof I can fit 5 Solar Frontier 150w panels from San tan solar.

I have 4 panels currently in use. Two strings in series that I’ve then used a branch connector to connect those strings in parallel to feed into my inverter. But with the VOC and the max voltage I was wondering if there is a way to work in the 5th panel, I need all the juice I can get. I’m worried that I might have to uninstall the panels and buy more expensive 200watt panels from rich solar and re-install those. Just trying to avoid thr expensive headache if I can, but I haven’t formed a full understanding of all the solar specs- which is where you all come in!

The guy at Trophy Battery has been amazing walking me through setting up my EG4, any help from you all in the forum would be much appreciated. It can get very overwhelming in the beginning of understanding solar even with the prep I’ve done.

Battery link: https://trophybattery.com/wp-conten...Battery-Specification-Book-2022-08-21-006.pdf

EG4 link: https://eg4electronics.com/backend/wp-content/uploads/2022/07/EG4-3000EHV-48-Spec-Sheet.pdf

Panels: https://www.santansolar.com/product/used-solar-frontier-150w-thin-film-solar-panel/

 

[MisterSandals]

What SCC do you have now?

If your SCC cannot handle 5S voltage, just get a second SCC like a Victron, smallest that does 48V. Get the Smart type with Bluetooth. If you plan on expanding later, get a bigger one.

 

[chrisski]

Can you get a sixth panel and use these as ground mount?

In the winter months, ground mount panels are at least twice as efficient as flat roof panels. I have a ground mounted array for my RV I move three times a day to max put production.

Choices are 5S if the EG4 can handle it; 2S2P as you have it; 2S3P as suggested; or get new panels.

 

[MbeBeefy]

I don’t have a charge controller I don’t think. I can definitely look into getting a 48v one. The way I currently have everything connected, with full direct overhead sun at 65° F I’m only pulling in 265W, which doesn’t seem like much considering I have 4 150W panels in use currently. I ordered a multimeter to test the panels (comes in the mail tomorrow) but a bad panel could explain why I’m not pulling in enough power?

 

[MbeBeefy]

Can you get a sixth panel and use these as ground mount?

In the winter months, ground mount panels are at least twice as efficient as flat roof panels. I have a ground mounted array for my RV I move three times a day to max put production.

Choices are 5S if the EG4 can handle it; 2S2P as you have it; 2S3P as suggested; or get new panels.

I have more panels since I bought them on a pallet. I’m not sure what you mean by using them as a ground mount- take them off the roof of the ambulance and put them outside on the ground and use them? The only thing I worry about that is they’re 40lbs a piece and huge, plus the added factor of cities and travel. It seems like a great idea for the right person though!

2S3P would be cool! I just wonder if my system could handle it, I’m not sure how to calculate that. I have 2 y branch connectors now F/MM and M/FF, so I would just get a F/MMM and M/FFF? And connect the extra panel solo or do I add it into the daisy chain of one of the sets of 2?

Thank you for answering my questions!

 

[MisterSandals]

don’t have a charge controller I don’t think.

Um, those panels have:

• Open Circuit Voltage (VOC): 98.7 V

If you have 2 in series directly connected to your batteries would be bad.

There has to be an SCC. Have any pics?

 

[MbeBeefy]

Um, those panels have:

• Open Circuit Voltage (VOC): 98.7 V

If you have 2 in series directly connected to your batteries would be bad.

There has to be an SCC. Have any pics?

I just have the EG4 48v, on their website it says “The EG4 3000EHV-48 is a 3000W all-in-one, multi-function inverter/charger; it combines the capabilities of an inverter, MPPT solar charger, and battery charger to offer uninterrupted power support in a single, portable-sized package.”

So I have a solar charge controller but I’m not sure how much it can handle? But I know 5 panels in series was too much, it was putting off a warning light.

 

[chrisski]

But I know 5 panels in series was too much, it was putting off a warning light.

Is this yours?

EG4 3kW Off-Grid Inverter | 3000EHV-48 | 3000W Output | 5000W PV Input | 500 VOC Input

Signature Solar provides solar panels, off-grid solar systems, grid-tie, and hybrid systems. Quality solar inverters, bifacial solar panels, complete solar kits, solar batteries. Featuring brands such as EG4 Electronics with their solar battery, LifePower4 and EG4 LLifePower4 and EG4 LL

signaturesolar.com

https://eg4electronics.com/backend/wp-content/uploads/2022/07/EG4-3000EHV-48-Spec-Sheet.pdf

The inputs are 500 VOC. Was probably cold pushing the voltage up. Overvoltages are bad and can destroy the unit.

2S3P would be cool! I just wonder if my system could handle it, I’m not sure how to calculate that.

the spec sheet linked above has 18 amps. How many amps total with three based off the rating per panel on the sticker?

Less than 18 total amps with all three strings would be good.

I think you are talking about moving this off the vehicle to a permanent installation which has more room.

 

[MbeBeefy]

Is this yours?

EG4 3kW Off-Grid Inverter | 3000EHV-48 | 3000W Output | 5000W PV Input | 500 VOC Input

Signature Solar provides solar panels, off-grid solar systems, grid-tie, and hybrid systems. Quality solar inverters, bifacial solar panels, complete solar kits, solar batteries. Featuring brands such as EG4 Electronics with their solar battery, LifePower4 and EG4 LLifePower4 and EG4 LL

signaturesolar.com

https://eg4electronics.com/backend/wp-content/uploads/2022/07/EG4-3000EHV-48-Spec-Sheet.pdf

The inputs are 500 VOC. Was probably cold pushing the voltage up. Overvoltages are bad and can destroy the unit.

the spec sheet linked above has 18 amps. How many amps total with three based off the rating per panel on the sticker?

Less than 18 total amps with all three strings would be good.

I think you are talking about moving this off the vehicle to a permanent installation which has more room.

I see! Okay I didn’t calculate the cold factor in when I was planning. Eventually yes I’d like to make a permanent ground mount for the system if I had land one day but for now I’m just focusing on mounting them to the ambulance for full time travel.

I tried googling how to find the amps, lots of forums have ways to find out but they’re not very clear about it. Here’s a picture of the solar panel specs-

 

[chrisski]

At 2.1 amps per string, you could do a lot more than 3 in parallel prior to reaching the limit.

As far as 40 lbs, per panel, you can’t do 3p2s without portable ground mount. For me, that could be two pvc pipes attached to the panel for legs, or simply leaned against the trailer.


9 of the portable 100 watt panels have legs and the last 3 flat 100 watt panels are leaning against the RV. 3p3s for the ones leaning on the RV with the other six in that array (3s2p) up top. Not hooking those three flat ones on the ground doesn’t stop charging at all except for what it makes.

Takes that much to run an absorption fridge on electric and use an electric hot water heater on the shortest days of the year in Arizona.

 

[MbeBeefy]

That’s awesome!! I have a small Bluetti EB3A that I will definitely do this with. Where do you normally get your panels from?

 

[chrisski]

I got the nine100 watt lion energy portable suitcase panels off Walmart.com. I got the three 100 watt renogy flat panels off Amazon.

When they’re not on the trailer, the 100 watt lion energy panels are providing power to a portable generator.