Anyone know of a settable solar charge controller under $500

Dr. Dickie

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1) I am getting into lithium iron phosphate (which was always my ultimate goal)

2) I have a 7s 20p 18650 (24V) battery I made for the fan in my solar shed

Currently I have a couple or 6 cheap 20-40 amp solar charge controllers, they work fine for lead acid. However, not so great for 18650 or LiFePO4
I was looking for a controller that I could set the voltages for (bulk, adsorb, float). I thought I found one, but no it is the same old crap where you can set voltages only up to 15V, which is no good for the 24 V battery I have. The current charge controllers I have (like most cheap ones) want to charge the cells to 4.1 V, I don't want to charge them that far, as the battery get very little to no use and does not need to be charged over 3.9 V.
Does anyone know of a decent solar charge controller that is under $500 (so not a Midnite solar--which I have and love, Outback, etc) that will allow me to set the voltages that I want.
I have looked high and low and cannot find one, so perhaps they do not exist. If I have to pull the trigger on another Midnite for my LiFePO4 so be in, but before I dive all in (I am only getting 8 280 Ah cells to start) I would like to do it on the cheap and scale up after I move and build the large LiFePO4 system.
Thanks
 
The MPT-7210A is settable and is cheap it would work for the 7s20p 18650, would work for LIFePo4 also but is too small for a battery of any size.
Later floyd
with appropriate panels (the panels have to be less than the voltage of battery pack)
how to configure the MPT-7210A.
View: https://www.youtube.com/watch?v=rC4rF62CHKY
 
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The MPT-7210A is settable and is cheap it would work for the 7s20p 18650, would work for LIFePo4 also but is too small for a battery of any size.
Later floyd
with appropriate panels (the panels have to be less than the voltage of battery pack)
how to configure the MPT-7210A.
View: https://www.youtube.com/watch?v=rC4rF62CHKY
THANKS.
I like it. About $60 from e-bay (less if from China), worth a look.
 
The MPT7210A's are limited to 10a on the output as I recall - so 24v * 10a = 240w max. Next higher that I've used is EPEVER. They are popular/been around a while. I have a 30a - 12/24v one and it is user settable thru the square black box accessory. Here's an example of a $93 30a base unit - https://www.amazon.com/dp/B075XHCT5K/ref=redir_mobile_desktop - with square black box sold separately for $30 - https://www.amazon.com/dp/B07FBKJFDF/ref=redir_mobile_desktop You would need both. EPEVER has several options that go up 80a / 48v.
 
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I have a 7210 and they are not MPPT at all You have to set the tracking voltage. They are ok for small panels I would look at the EPever ones Or Check out Adam Welch on YT for other really cheap mppt/PWN charge controllers Adam Welch
 
you need a mppt for the 7s20p? Victron smart solar are pretty well priced. Fully configurable including limiting charge current should you want that. All through the phone app and bluetooth. Very easy to use. I have a small 4s10p lifepo4 portable pack (~400wh) and I charge it off my 48v mini-wall. I use the 50-60v that my 15s wall runs at as the input for the 100/15 smart solar mppt that is in the little power pack. Charges it and floats it really well. I have a 150/35 for my main wall. It is just a little hobby thing that I run small things with. That has (2) sunpower 360w panels in series and usually runs about 120 input from the solar.

The smaller victron mppt do 12 or 24v batteries and then when you start getting into the larger ones you jump up to 48v capability. The little 100/15 (that is up to 100v solar input and up to 15 amps charging output) was a little over $100. Maybe $120? The 150/35 was more like $330.

I also have another 100/15 that I use to float charge some lead acid cells from the 48v wall. I also drive that one directly off battery voltage. Also works great. I know that I'm using the MPPT as a DC-DC smart charger but I can also plug in solar to the same input and use that source so it works for me.
 
The MPT7210A's are limited to 10a on the output as I recall - so 24v * 10a = 240w max. Next higher that I've used is EPEVER. They are popular/been around a while. I have a 30a - 12/24v one and it is user settable thru the square black box accessory. Here's an example of a $93 30a base unit - https://www.amazon.com/dp/B075XHCT5K/ref=redir_mobile_desktop - with square black box sold separately for $30 - https://www.amazon.com/dp/B07FBKJFDF/ref=redir_mobile_desktop You would need both. EPEVER has several options that go up 80a / 48v.
I looked at those, but when they say "settable" my experience is, they ONLY allow you set user values for up to 15 V. That is pretty common on those types of charge controllers--I have about 5 of them.
This EPEVER says:
User programmable for battery types, load control etc.
That means you can select from THEIR settings of lead acid, lithium, gel, etc, BUT you cannot set your own voltages for these settings.
Do you have one and know that you can truly set value for them?
 
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you need a mppt for the 7s20p? Victron smart solar are pretty well priced. Fully configurable including limiting charge current should you want that. All through the phone app and bluetooth. Very easy to use. I have a small 4s10p lifepo4 portable pack (~400wh) and I charge it off my 48v mini-wall. I use the 50-60v that my 15s wall runs at as the input for the 100/15 smart solar mppt that is in the little power pack. Charges it and floats it really well. I have a 150/35 for my main wall. It is just a little hobby thing that I run small things with. That has (2) sunpower 360w panels in series and usually runs about 120 input from the solar.

The smaller victron mppt do 12 or 24v batteries and then when you start getting into the larger ones you jump up to 48v capability. The little 100/15 (that is up to 100v solar input and up to 15 amps charging output) was a little over $100. Maybe $120? The 150/35 was more like $330.

I also have another 100/15 that I use to float charge some lead acid cells from the 48v wall. I also drive that one directly off battery voltage. Also works great. I know that I'm using the MPPT as a DC-DC smart charger but I can also plug in solar to the same input and use that source so it works for me.
Never seen a cheap Victron, and there are a ton of chargers that can run the packs, problem is, you can't set the voltages you want--oh, many say you can, but you can only do that for a 12V system.
I did look at this one:
Victron-SmartSolar-MPPT-Controller-Bluetooth
But it does not say user programmable. And generally, "smart" means, we know what to do, just do as we say.
 
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That means you can select from THEIR settings of lead acid, lithium, gel, etc, BUT you cannot set your own voltages for these settings.
Do you have one and know that you can truly set value for them?
Not true. The black box / user mode will let you set what you want that is range of the unit - you just go to user (custom) option which is only available from the black box. The EPEVERs come in 12/24/36/48v options so not sure where you saw 15v max?. I used my 12/24v model on my 1st 24v 18650 battery and set it OK :)
 
Not true. The black box / user mode will let you set what you want that is range of the unit - you just go to user (custom) option which is only available from the black box. The EPEVERs come in 12/24/36/48v options so not sure where you saw 15v max?. I used my 12/24v model on my 1st 24v 18650 battery and set it OK :)
I wasn't saying it was for that charger, but that is what it means for all the chargers I have.
So, you have this charger and know that I can set custom voltages for a 24 V system?
the black box you mention is the MT50 Remote Meter right?
I need that to change parameters?

Thanks
 
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I wasn't saying it was for that charger, but what it means for all the chargers I have.
Didn't mean to sound harsh :)

So, you have this charger and know that I can set custom voltages for a 24 V system?
Yes. Here's a youtube (there are a few) showing the EPEVER 'black box' ..... He's doing a 12v battery but the 12/24v unit will also do 24v battery voltage range.
View: https://youtu.be/4msUDzI9Voo


the black box you mention is the MT50 Remote Meter right?
I need that to change parameters?
Yes - that MT50 Remote Meter is not just a meter but also gives access to the user definable settings that aren't available on the menu of the 'main unit'. Not sure why it's that way.

 
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Didn't mean to sound harsh :)


Yes. Here's a youtube (there are a few) showing the EPEVER 'black box' ..... He's doing a 12v battery but the 12/24v unit will also do 24v battery voltage range.
View: https://youtu.be/4msUDzI9Voo



Yes - that MT50 Remote Meter is not just a meter but also gives access to the user definable settings that aren't available on the menu of the 'main unit'. Not sure why it's that way.
Didn't sound harsh.
Ordered it. THANKS.
Just what I was looking for!
AND, I got it in and it does as stated, works perfectly for what I wanted!
Thanks
 
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Never seen a cheap Victron, and there are a ton of chargers that can run the packs, problem is, you can't set the voltages you want--oh, many say you can, but you can only do that for a 12V system.
I did look at this one:
Victron-SmartSolar-MPPT-Controller-Bluetooth
But it does not say user programmable. And generally, "smart" means, we know what to do, just do as we say.
Perhaps it depends on your definition of cheap. $120 for a smaller highly competant controller seems cheap to me. And backed by actual service vs the chinese stuff. You can load a preset if you want or you can configure all kinds of stuff about these. It is incredibly easy and can be changed on the fly. Plus it logs data so you can see graphs of production, max voltage, solar wattage and all that stuff. I have my 150/35 set to charge to 60v (15s system 4v/cell) and I have my 100/15 for my 4s lifepo4 pack set to charge to 13.8v (3.45v/cell).

The model you linked is what I'm talking about. To each his own.
 
Perhaps it depends on your definition of cheap. $120 for a smaller highly competant controller seems cheap to me. And backed by actual service vs the chinese stuff. You can load a preset if you want or you can configure all kinds of stuff about these. It is incredibly easy and can be changed on the fly. Plus it logs data so you can see graphs of production, max voltage, solar wattage and all that stuff. I have my 150/35 set to charge to 60v (15s system 4v/cell) and I have my 100/15 for my 4s lifepo4 pack set to charge to 13.8v (3.45v/cell).

The model you linked is what I'm talking about. To each his own.
No, no. I do consider that cheap. It is like the only Victron which is under several hundred dollars. It just does not indicate that the parameters can be user set--that I could see, and I have been burned several times by manufacturers who use deceptive language to make it SEEM like you can define the parameters, but you cannot.
If the other charger does not do what I need, then I will definitely be getting the Victron.
 
No, no. I do consider that cheap. It is like the only Victron which is under several hundred dollars. It just does not indicate that the parameters can be user set--that I could see, and I have been burned several times by manufacturers who use deceptive language to make it SEEM like you can define the parameters, but you cannot.
If the other charger does not do what I need, then I will definitely be getting the Victron.
Right. Except they do advertise it. And I'm telling you from personal experience. You asked for solar chargers under $500. I'm not sure what you expected.
 
Right. Except they do advertise it. And I'm telling you from personal experience. You asked for solar chargers under $500. I'm not sure what you expected.
No, no. You are right, I got it. I do NOT see it in the advertising of the units that they are fully programmable by tge user, and as I say, I have been burned many times.
 
@Dr. Dickie I initially went with MakeSkyBlue, (MrPower or whatever they may be called next week), MPPT Charge controllers. One blew the mosfets out of it and the manufacturer was a typical representative of "Name of country here" and said I hooked it up wrong, it was my fault, even though the other 2 where hooked up the same BLA BLA BLA. I finally was offered a replacement motherboard for a reasonable $ amount plus shipping. In the meantime I replaced the blown MOSFETS and it worked again.
All in all they worked OK but just cheep. Fans started growling, voltages were not accurate. Occasionally overcharging, the normal "Name of country here" problems you have with these "quality items" that cost $10.00 to make and get sold for $120.00.
As always I should know better you get what you pay for.
1636037498875.png
I finally bit the bullet and bought 2 Victron MPPT 150/60 tr Controllers. One was a good deal from a member on this board and the other was a Facebook marketplace find. Both at a reduced price of $400 each.
Now with the Venus OS installed on a Raspi I could get rid of a bunch of manual reporting equipment and such and have all of it go to influx and grafana. The performance of the MPP Tracking software is far superior to "Name of country here" imports, the Voltages are accurate, the charge controllers are bulletproof, extremely flexible with settings and I don't have to worry about them. Ahh peace of mind.
And yea you guessed it you really do get what you pay for. :)
Wolf
1636038399544.png

 
@Dr. Dickie I initially went with MakeSkyBlue, (MrPower or whatever they may be called next week), MPPT Charge controllers. One blew the mosfets out of it and the manufacturer was a typical representative of "Name of country here" and said I hooked it up wrong, it was my fault, even though the other 2 where hooked up the same BLA BLA BLA. I finally was offered a replacement motherboard for a reasonable $ amount plus shipping. In the meantime I replaced the blown MOSFETS and it worked again.
All in all they worked OK but just cheep. Fans started growling, voltages were not accurate. Occasionally overcharging, the normal "Name of country here" problems you have with these "quality items" that cost $10.00 to make and get sold for $120.00.
As always I should know better you get what you pay for.
View attachment 26431
I finally bit the bullet and bought 2 Victron MPPT 150/60 tr Controllers. One was a good deal from a member on this board and the other was a Facebook marketplace find. Both at a reduced price of $400 each.
Now with the Venus OS installed on a Raspi I could get rid of a bunch of manual reporting equipment and such and have all of it go to influx and grafana. The performance of the MPP Tracking software is far superior to "Name of country here" imports, the Voltages are accurate, the charge controllers are bulletproof, extremely flexible with settings and I don't have to worry about them. Ahh peace of mind.
And yea you guessed it you really do get what you pay for. :)
Wolf
View attachment 26432

Yeah, if this was for something important, I would have popped for something of quality right at the start. This was just for a battery I threw together with the 18640 cells that did not pass muster for my Powerwall. It only has to bring through a charge for the odd chance that the shed gets hot AND there is insufficient sunshine to run the fan (probably never happen, but I had the cells lying around, so what the heck).
I have the EPEVER and when it stops raining and blowing outside I will try it out.
The stupid thing is, I was this close to ordering EPEVER but could not get definitive info that I could set the voltages I wanted, so I fell for the deceptive advertising that you could set them and went cheap again. Of course, just like the 5 other cheap solar controller I have, you can set custom voltages....so long as it is not greater than 15 V (this for 12, 24, 48 V controllers).
I do appreciate the feedback. I have one of those MrPower systems sitting around here somewhere, I never even though of that--got it about 5 years ago and it did not do what I wanted back then. I am still going to need a good controller for the LiFePO4 system I am going to build next month (if I get my cells as promised, there is some shenaigans going on with tracking numbers from SANBEN--I hope I am not being played by those folks). They put up a tracking number saying they shipped. Then changed the tracking number, but damned if I can find out what they are using, so the number is useless. I have tried looking for an Aliexpress delivery where I can put in the tracking number, but can't find one. I am waiting to hear back from them; hopefully by Monday.
For the LiFePO4 system, I do think I likely will try a Victron for that system.
 
The EPEVER worked perfect for the fan battery.
I DID get the Victron controller for my future LiFePO4 cell (which are currently Lead Acid).
When I hooked the Victron, of course I have hooked up solar charge controllers so many times I did not bother to look at which was supposed to be battery and which was PV.
Victron has them backwards compared to all the other solar charge controllers I have. I actually thought it was defective and did a return through Amazon. It was only after I dropped it off at UPS did it dawn on me that I probably hooked it up backwards (yes, it is clearly marked).
I hurried back to USP and got it back, and I love it.
Funny Amazon has no way to cancel a return, seems silly.
 
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