Although you can get cheaper per watt for larger panels the best buy on 100w bifacial from Ecoworthy at Ebay is 2-100w for $117 with a 20% off promotion. Pick up 4-2 packs and with the promotion that would be ~$372 https://www.ebay.com/itm/126144558396
Test run with a small system first?
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I can see what the shipping on that would be. the shipping on any panel from santan solar is a killer. far more than the actual cost of the panels. oof. Maybe there is a decent used panel seller around Atlanta Georgia. I live close enough to make an easy drive there.
Free shipping. But it looks like you might have found a better deal!
maybe. Messaged the guy to see if he still has panels in stock.
Ok. Cool. I think I may have the panels nailed down. I can get 6 for basically $100/each. They have these specs:
that makes the cost about 0.455 $/W. Not too bad. About 1380W of power if I get 6. Pretty neat. If strung together, it is 222V VoC, 180.6 VMP, still 8.3 Amps? And its under the 600V limit. I guess since they have a 15A fuse rating I should use a 15 amp fuse between the panels and inverter/charger/battery?
Need to figure out how to pick them up now. lol
that makes the cost about 0.455 $/W. Not too bad. About 1380W of power if I get 6. Pretty neat. If strung together, it is 222V VoC, 180.6 VMP, still 8.3 Amps? And its under the 600V limit. I guess since they have a 15A fuse rating I should use a 15 amp fuse between the panels and inverter/charger/battery?
Need to figure out how to pick them up now. lol
Sounds like a good deal. With just one series string (6S) you do not even need a fuse. A 2 pole 12-15a DC breaker near your SCC or AIO for isolation however is really handy. Also with only 7.89a max current you can get away with smaller PV wire depending on the total distance. However it does not hurt to go larger on the wire gauge if you intend to ever increase your array size. With 12awg your good to 20 or 25a.
I think you will find that the 1380w PV will make for a good power source for many of your loads. Depending on the day it ought to give you 4-8kWH/day.
I think you will find that the 1380w PV will make for a good power source for many of your loads. Depending on the day it ought to give you 4-8kWH/day.
MisterSandals
Participation Medalist
You will at least want/need a switch as a solar cutoff switch. A good quality 15A DC breaker would work well. A higher amperage breaker becomes more like a switch but still ok.
Yeah. that is true. I could probably do everything I need to do with a 4-5kw system purely on energy too.
will do. I may make a list of components that I need and stop at an electrical supply store while I'm getting the panels. They're in a bigger city anyways and there isn't much around where i live.
I may be able to get everything except an inverter/charger/all in one or whatever i decide to get. lllol
Might look at Temco for your PV wire, cable and lug needs. TEMCo Industrial LLC
I find their PV wire and welding cable to be of very high quality. You do have to put on your own lugs and MC4 connectors but it is all part of the fun.
I find their PV wire and welding cable to be of very high quality. You do have to put on your own lugs and MC4 connectors but it is all part of the fun.
I need to figure out a temporary mounting solution now too. lol
Looking at this diagram as a sort of guide, I would want a cutoff switch between the solar panels and the battery charge controller and I would want a fuse on the positive wire running from the battery and the inverter? And one between the charge controller and the inverter? I won't have any DC loads so it doesn't really make sense to have that section anyways. If I did, I would only need a DC to DC converter if I wanted to connect a 24v load to a 12v system right? The fuse block in this drawing would be an equivalent of a DC breaker panel if i am understanding this properly.
with a system of my size and considering that its not going to exceed 10 amps and the VoC is ~220Vdc, would that mean I would need a 60 amp charge controller if i just had one string (actually seems like 80amps looking at some brands especially if I go for the 6 panels)? I am trying to understand how charging controllers work now. It seems like charge controllers dont come with more capabilities until they get beyond 60amp just from looking around at cheaper ones. If I put the panels in series, the VoC would be cut in half right but the amps would double and three strings would be 3x in the respective directions right? how would that affect the power output? Multiple strings would require a combiner box would it not?
Other than the DC switch and fuses (I guess they can be DC breaker switches too), the only other thing I would need is a small subpanel for the loads, something to mount all the hardware on, and the wiring and that is really it. Oh and also some means to monitor what the system is doing.
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I want to understand how both work but I am somewhat leaning towards AIO because it seems like it would be cheaper. The only way that separate SSC and inverter charger would be cost effective is if i had a smaller system (it seems).
With that PowMR AIO, it seems like its the cheapest option for something that won't be extremely jerry rigged. not that jerry rigging is a problem. lol
In terms of installation a separate SCC connection to the battery is wired independent of the inverter cables to the battery. The AIO is more bi-directional. So the wires and circuit protection from the SCC to battery would be sized based on its output rating. Very few SCC can have the charge amperage set to anything but rated. However most AIO's will allow you to set PV amperage for charging. This can be handy if your battery is unable to carry full amperage your solar powers could deliver.
Some inverter chargers will perform ATS that AIO's have. Some also have ability to set some parameters for operation. High quality ones like Victron have a Eco-system of things and tons of monitoring options. You will find that there are two camps on the PV Off grid side of things. Those that say individual components are the only way to go and those that prefer the all in one box approach.
Just for grins, after seeing the Sumry 4kW AIO I made an offer on Ebay for it at $300 this morning. If they go for it* I likely will post a review of it on the Forum. It looks like this is their first US 120vAC voltage model of AIO (They show several 230vAC models but no listing of this one) though their website claims to have been in the Solar inverter business since 2004.
* Unlikely but you never know if you don't try.
3/9 Edit: My offer for the Sumry 4kW was declined. Considering the lack of information about it, no downloadable manual and the discrepancy in some of their specs (I saw both 110a, 140a and even 150a mentioned on the ad for PV charging) it is a gamble to try such a unit. Not worth more than I offered. Maybe not that much even.
Some inverter chargers will perform ATS that AIO's have. Some also have ability to set some parameters for operation. High quality ones like Victron have a Eco-system of things and tons of monitoring options. You will find that there are two camps on the PV Off grid side of things. Those that say individual components are the only way to go and those that prefer the all in one box approach.
Just for grins, after seeing the Sumry 4kW AIO I made an offer on Ebay for it at $300 this morning. If they go for it* I likely will post a review of it on the Forum. It looks like this is their first US 120vAC voltage model of AIO (They show several 230vAC models but no listing of this one) though their website claims to have been in the Solar inverter business since 2004.
* Unlikely but you never know if you don't try.
3/9 Edit: My offer for the Sumry 4kW was declined. Considering the lack of information about it, no downloadable manual and the discrepancy in some of their specs (I saw both 110a, 140a and even 150a mentioned on the ad for PV charging) it is a gamble to try such a unit. Not worth more than I offered. Maybe not that much even.
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Interesting read. I just built my own portable test system. I purchased 6 100W panels but am currently using 2 for the testing. Victron SmartSolar MPPT 75/15, 100aH LiFePO4 battery, an old 500W inverter I had lying around and a Raspberry Pi running VenusOS with extras installed so I can feed my collected data to my HomeAssistant dashboard. Added 3 relays and a couple temp sensors for fun. Have a Victron Phoenix 375W 12V inverter to be installed this weekend so I can track more data on AC usage. It's all mounted in a plastic crate that is strapped to a hand truck so I can move it around the yard and test various locations. Looking to put in a ground mount system so I figured this little stand alone rig was a good way to go.
yeah. im in the easy camp even though I think its good to understand the basics of how each component works together. To me, it seems like it only makes sense to do individual components if the system is really small or if you have use cases that warrant that type of granularity. An AIO can operate like a grid tied or off grid inverter and charges the batteries. Its a device that works for most applications and its probably why there are more coming out. It makes the wiring super simple. Just 4 connections.
I will see if I can find one of those PowMRs on ebay, but it would probably be better getting a new one. Did you ever figure out why the PowMR was measuring incorrectly?
I like the fact that Victron stuff can connect to raspberry pis, but i have a hard time understanding their product line up and what their prices are. They have AIOs but i'm not sure what sizes the offer or anything. It would be super cool to figure out how to connect a raspberry pi to the AIO i'm currently looking at but I don't know.
Their line up can be a bit confusing for sure until you get it. The reason I went with them is the fact that the VenusOS software is available to run for free on a Pi. No need for a Cerbo or any of their GX products if you want to roll your own. The amount of data I can collect and analysis would cost me much more with another vendor. I feed all the data to a database via MQTT and I can slice and dice it anyway I want without reliance of cloud services. I can also store as much data and for as long as I want. That said their tools for monitoring your system live are really good. For the kind of location analysis that I'm doing their gear totally fit the bill and was really plug and play.
Will I go with them for my planned full home 48V split phase system? Not sure yet. There are a lot of AIO boxes that are significantly cheaper and at that point may not need all the stats that I'm currently interested in.
Most of them on Ebay are new. No I am not sure why the incoming PV wattage seems to be off but likely it is a function of type of DC current measuring it does. If I have not already mentioned it it is a good idea to have a DMM and a DC* clamp on ammeter in your tool box.
*Many AC clamp meters don't measure DC current.
Edit. If you are not a regular Ebay user it would not hurt to do some reading up on best practices. Same for Aliexpress and for that matter Amazon.
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Yeah. I will see which one Will recommended. I forgot. lol. I will also see what kind of monitor I can pair with it anyways. may take me a minute to figure that out. hopefully something cheap. Actually. no. I could just try to rip data from it and just correct it. why not? lol
Yeah. its great that they have such an open system. It seems like many other ones have communication protocols that are compatible with home assistant or something, but it would take some programming to figure it out.
