Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Inexpensive Charger Controllers for 24v battery pack.
#1
So before someone goes and recommends me a high quality MPPT… I already own a few and understand the quality and benefits.  I really enjoy my Victron and Genasun units, but I need something I am willing to loose if it gets stolen as its going to be deployed on mountain tops for temporary radio repeater use.

I know there a bunch of inexpensive options out there, but not sure what to consider.  I am looking for something 12 or 24v compatible that has adjustable voltage parameters.  I was going to use either a 4s or 7s pack and adjust the voltage of the max charge.

Any recommendations?
Reply
#2
If you see my build, I use a eSmart3 MPPT controller. I bought a 60A version for around $150 I believe. Only had it running for 6 months though but I've seen others on Youtube with them running for longer without issues.
Reply
#3
(03-19-2019, 11:45 PM)not2bme Wrote: If you see my build, I use a eSmart3 MPPT controller. I bought a 60A version for around $150 I believe. Only had it running for 6 months though but I've seen others on Youtube with them running for longer without issues.

Its physically too big, plus it cost too much... needs to fit into something like an ammo can and be cheap enough to throw away as I am going to abandon this thing on top of mountains for months at a time.

Here is a $100 Genasun MPPT that fits into a 30 cal ammo can... its going to be something similar but with radio equipment inside of it and a lithium battery.



Reply
#4
I guess it depends on what inexpensive is and how much amps you're looking at. You can take a look at a MPT-7210A. It's under $40 although I've heard about fan issues but can be modded with better fan.
Reply
#5
I have one of those too, I guess I can use it. It’s an ok charge controller… makes a better general purpose DC-DC IMO which is what I have been using it for. I use it as a boost battery charger for going from 12v to 24v for maintaining the 24v pack in my truck.

Still, I guess it would work find considering its one of the very few boost controllers on the market and then I can use a single smaller panel, like a 20 watt.

There was a person a while ago that mentioned a really dirt cheap PWM controller he used which has user adjustable voltage limits. They ended up using a 3s or 4s pack and adjusted the voltage limit to not overcharge. I was thinking of doing something similar. The radios native voltage is 7.4v nominal, but the “battery eliminator” is basically as 12 to 24v buck converter.

Radio
https://powerwerx.com/wouxun-kg-uv8t-tri...held-radio

Battery Eliminator
https://powerwerx.com/wouxun-kguv9d-battery-eliminator

I haven’t measured it yet but the load / consumption is very small… uses 5 watts for transmitting, and probably 50-100mA when on standby… 95% of the time its just going to be on standby until I key up the repeater.
Reply
#6
Some 24V Lead-acid chargers can be set to voltages better matching litium in 7S configuration, maybe they are cheaper. Since the load is so small, a DC-DC converter could be used for a 12V supply to the radio with minimum losses.
Reply
#7
I have the mpt7210a and it's ok and works well but your battery voltage needs to be higher than your Solar Voltage so you would need < 20V solar Panels when your batteries are down at 21V.
Reply
#8
(04-01-2019, 07:27 PM)jdeadman Wrote: I have the mpt7210a and it's ok and works well but your battery voltage needs to be higher than your Solar Voltage  so you would need < 20V solar Panels when your batteries are down at 21V.

I guess I could do that, even though I didn't want to use that controller... ill test it out just for fun to see how it works.  It really might be my best route at this point.

I don't really drain past 3vdc per cell, so 21v is about right.  I have it connected to some lead batts just for panel testing... observed PV voltage stays below 21v...

Reply
#9
Music 
I have 2 of these from Amazon. $45 They are MPPT charge controller that will step up the voltage. I use a 12 volt panel on it so it would work with 7s pack and its small in form factor.
 

Reply


Who read this thread?
68 User(s) read this thread:
daromer, Sean, Korishan, PAF, Franky Beuselinck, jdeadman, wim, watts-on, Dan Lim, Stefaan De Ridder, Mazlem, Geek, ChrisD5710, Oz18650, not2bme, Filip, gpn, viralprankster, Chablis_m, Headrc, Crimp Daddy, Zvonko000, choncy12, Cherry67, Sholphin02, Walde, Riplash, 100fuegos, bukvaahmed@gmail.com, ungp, chuckp, emuland-metroman, Beholder, clupton, Wolf, camthecam, Dallski, PaulDane, kevinjaye, Dchuk, Powersaver, Richard, fleming, rhedbatt, valueseek, Havskum, strat24v, rearden, Omalik, BarryG, 100kwh-hunter, JimU, loyd, Doin it, juanjo57, MarshallPower, Shikijebbi, bairleafarm, Eggly, friedpenguin, schmo, rochv, BitcoinBandit, foamovercast, lange5766, romcek, Jacob89, cnrd

Forum Jump:


Users browsing this thread: 1 Guest(s)