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Will all this work right together for a 24v system

EddieM

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Sep 19, 2020
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Is this all the right items to make this work together.?

I have 4 SOK 100ah Batteries - Have them here

EPEVER MPPT Solar Charge Controller 40A 150V PV Solar Panel Controller - Have it here

Six - Newpowa 200W 12V Monocrystalline Solar Panels 17v each (1200) watts- have them here

Giandel 24 Volt 2000W Pure Sine Wave Power Inverter DC 24V to AC120V - Not ordered yet

Blue Sea Systems ST Blade ATO/ATC Fuse Blocks - On order

uxcell New BIG-Size Voltage Converter Regulator DC/DC DC 24V to DC 12V 40A 480W Buck Transformer Waterproof

T Tocas 50 A Circuit Breaker - On order


A lot of this I ordered from clicking on the recommended list of items on the site.

I have all the wires ready to go and mounts and shut off switch.
This will be installed in and on a 2000 ambulance conversion.
I do not feel I need a grid tie system or battery charger as I feel the 1200 wats should cover it all and I am down south with plenty of sun.

I plan to put in a Mini split 9000BTU AC as well. Would the 2000 watt inverter cover this or should I pay more and get a 3000 watt inverter?

Would be running the mini split AC at times in summer, a Maxxair vent fan. 12v fridge I think it is 60 watts when running at full when compressor is on, A 32 to 42 inch TV, some led lights and a Mac PC or laptop they both take low power but would run a large PC monitor hooked to it.

For fuses I am not sure what size I would need to order for this system from this list https://www.mobile-solarpower.com/fuses.html

Thanks
 
You need to post the full specs for the solar panels to know if they will work with the chosen charge controller. Do you have an idea of how you plan to configure the panels? 2S3P? 3S2P?

You mention a 50A breaker. What is the intended use?

You state you have all of the wires. You should create and post a wiring schematic with everything. Include wire sizes and expected lengths. Show all fuses and breakers. Put question marks on things you don't know such as a given fuse size or wire size.

All of the main components you listed will work together. But no one can tell you whether they are what you actually need or not without more details. You should do a full energy audit to figure out what your energy needs are. Then you can decide how much battery you need, how much solar you need, and what size inverter you need. And all of this should have been done before buying anything to avoid possibly having to return items in exchange for different items.

As for the mini split A/C you should look at its specs for how many watts it uses when running. But keep in mind that such items have a much higher startup surge. So even if, for example, it runs at 1200W it might actually need a 2500W inverter just so it can handle the brief initial startup surge. There are lots of threads here on mini splits. You might be able to find specific about startup surges while searching through those threads.

Fuse sizes are based on chosen wire sizes and the amount of current that will be running in the wires. Posting your diagram with enough info will allow people to help you figure those out.
 
Is 17V the VOC? At $210/panel, I’d probably go Rich or windyNation 100W panels (~$90/100W), drop the buck converter, and with the $200+ savings buy the windyNation 100W kit and a walmartha grp27 (about the same cost as the savings) and have a 12V independent system.
The Rich and Windy panels are like 19.xVOC but 17 is adequate with lithium batteries.

That may not make sense for you because I don’t know your 12V requirements. But for me I’m 100% 12V LEDs for lighting, and I have installed ports for usb and have one ‘lighter-type’ 12V socket if I ever want to charge my tiny handheld marine VHF. (although at next mod maybe this fall I’m installing some sae sockets because the two or three 12V things I might want to plug in are all converted to sae- I like them: clean, shallow, and don’t require the friction of the tabs on the side of the figgy plug to be dependable.)

So I don’t know what your use for 12V is. I personally know someday I’ll need to go 24 or likely 48V battery bank - but I’ll always maintain a basic 12V system because there’s little to fail an even my jeep could charge it for lights if something happens. I like redundancy- my current 12V system can run the fridge, lights, coffeemaker, and the 3V step-down for the water heater ignitor. So all the essential needs are covered. What I don’t have and will eventually capitulate to is power for table saw, other tools, welders.

In your case: 12V fridge; is that a real fridge or a cooler on steroids? 60W… my 120V 5.x CF fridge runs 60-80W and has a freezer compartment. Looking forward to upgrading next year to a 10-12CF and maybe a small chest freezer if I want to stockpile frozen foods.
I see no big advantages to the compressor-run coolers other than portability and 12V ability in a boat or car, and they’re wicked small for living out of.
Just thought I’d mention a 120V fridge isn’t a power hog much over what you’ve suggested.

Hope this helps- just trying to keep you thinking wide and not stuck in a corner.
 
The solar panels are New powa - Max Output:200W, Current at Pmax (Imp): 11.76A, Voltage at Pmax: 17.0V. I have all six of them here all ready I got them in sets of two as I saved money up for them.

The 50amp breaker I got as is says to on this page for a 40amp charge ccontroller https://www.mobile-solarpower.com/2000-watt-24v-solar-system.html

Its Hard to do a full full energy audit as this is a new build I do not have some of the items yet to even know what they will be. Like the TV I have not got that yet. just looking at the maxxair far sitting here it dose not say how much power it uses.
A box of RV LED lights I have says 6 watts each 12 volt i don't think i would ever use more then two of them on at once.

My Mac uses around 30 watts but can be less at times. the extra monitor i have is a HP and just looking at it is has no spec on it to see.

Would have a cell phone charging plug to - not sure how much power that uses.
Then we have a 12 volt ATT mobley internet device that is very small it has no power info on it at all. Its not much we used it in a RV in the past.

Will need some kind of 12v water pump to bring up water to a sink not sure what much power that would use.

The fridge we have is a ICECO JP50 12v with one SOK 100ah I have run it for over two days with no problem with power left.
One guy reported - Was getting 37-40 watts at ECO mode and 57-59 watts at MAX mode. During idle, I was reading 3 watts. Using a KillaWatt to measure. After it gets cold we run it in the ECO mode. Its been on for months plugged in we use for keeping drinks cold in our house.

Can not think of anything else we woud be running oo maybe a cell siginal booster I have

I will work on a chart
 
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Wildhat guess the tv if led will be 80W
12V water pump 6A or a bit more so 80W

Depending on the cell booster- the cheap one I bought said 60W but was damaged and never tried it. I think the wart was 4.x volts? Wilson ($1000) is 20W
 
The directional receiver boosters may provide better performance. That’s omnidirectional isn’t it?
 
Yes it says omni directional we used it in our RV we had. We had a 40 foot RV we traveled in for a Year it worked.
I also still have a wifi ranger we used in the RV to.

This ambulance build will not be for full time living it is our work truck and in summer we want AC in the back when parked. We work on the beach and spend a lot of time waiting so we can wait in the back of the truck with the AC on.
We get a lot of sun light here more then 5 hours a day for most summer days more like 8 hours.
Then in the off season we can take some trips in it and hit some small RV parks and other places and be covered. But our off seasion is more winter so we need heat more then AC then. Will Just use a small space heater and plug in at parks for that.
The ambulance has a 8x14 by 6 tall box on the back and is super well insulated.
 
What fuse amp size should go before the inverter?. I think I will go with a 3000 watt just to make sure.

I have everything except the inverter and the solar controlar and the right fuses.

I have a second system i built using one SOK 100ah battery I will be adding to the other three I have to go into the truck.
I have a 206 AH SOK on order to put in my smaller home system to back up a freezer for power outs and run some lights.
 
You should put a breaker (or switch and fuse) between array and SCC. 15A sufficient, 20A a little better.
Just make sure the breaker can handle the Voc of the array. "Normal" breakers are not made for 150V.

What fuse amp size should go before the inverter?. I think I will go with a 3000 watt just to make sure.
3000W / 24V / 0.85 efficiency = 150A for your wire calculation. 1/0AWG is more than enough and it can fused up to 300A if high quality and not bundled. So between 150A and 300A. 200A would be a good choice.

You should have bus bars between the batteries and all of the other components.

battery positive -> main battery fuse -> main cutoff switch -> positive bus bar
battery negative -> optional shunt/battery monitor -> negative bus bar

The each component would be:

component positive -> component fuse/breaker -> positive bus bar
component negative -> negative bus bar

where each component is your SCC, inverter, 24->12V DC-DC converter.
 
I have a - Blue Sea Systems 100 Amp Mini BusBar with 4 studs and a cover, 2315 - that will be in tomorrow. so I should get a second one then

Still not sure what solar controller to get.

Would this one be good for this system - EPEVER MPPT Solar Charge Controller 40A

Or a Victron Energy SmartSolar MPPT Tr 150V 45 amp
Or
Victron BlueSolar MPPT 100V 50 amp 12/24-Volt Solar Charge Controller

or some other?
 
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1200W solar / 25.6V battery = 47A max charging.

A 100V Victron would be too low for 6S array but 3S2P would be great.

You have a nice system so far. If you got a cheaper unit as your SCC (heart and brains), you’d probably regret it. I have a couple Victron and a big Morningstar MPPT…best decisions/investments I’ve made!

I would think the Victron 100/50 a great choice. A beefier ($$$) 150 if you think you will be expanding down the road. This will be your SCC for many years to come (5yr warranty anyway).
 
I have a - Blue Sea Systems 100 Amp Mini BusBar with 4 studs and a cover
That's way too small. Treat the bus bar just as if it was one of the wires. Since you are connecting 1/0AWG wire to it the bus bar must handle as many amps to be safe. So you need a bus bar that can handle at least 300A. However, if you end up choosing a 200A fuse as was discussed, you could use a 250A bus bar since the fuse will still be the weak point (that MUST ALWAYS be the case).
 
what about a two 30amp solar controller system. How would that work to take two 24 volt side into one? Somthing
 
That's way too small. Treat the bus bar just as if it was one of the wires. Since you are connecting 1/0AWG wire to it the bus bar must handle as many amps to be safe. So you need a bus bar that can handle at least 300A. However, if you end up choosing a 200A fuse as was discussed, you could use a 250A bus bar since the fuse will still be the weak point (that MUST ALWAYS be the case).
it dose seem a bit small got it in today so I ordered a 300A version if I like it I will order a second one and send this smaller one back.
 
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