diy solar

diy solar

Cheap power supply for top balancing (tested and works well).

Great information John. Is there a supply you would recommend that is a little better quality and more then 10amps?

Certainly, I strongly recommend the Riden RD6018, 18 amps output:


I could also recommend the Tekpower 40 amp supply, except there is a new version I haven't tested yet. I bought the one I have on Amazon (15v, 40a) but they no longer sell it. However, I'm pretty sure this is the same manufacturer:


The original Tekpower I purchased from Amazon, and is no longer in stock. Tekpower does have it for sale on their website:

 
I’ve been using the cheaper Longwei as a charger on my 24v A123 batteries since June last year.
The fan is quite noticeable but my tinnitus blends well with it. ?
It takes about 9hrs to recharge from 20% DOD back up when it drops the current down to 1.2a ? Thats where I want them full. I start out set at 28.6v 10a. It has done its job well, never been a problem since I’ve owned it.
I did do the 10g wire upgrade on the leads did away with those banana plugs, but I still use the alligator clips to attach to the batteries. Small acceptable loss.
I’m pleased with it for what a paid and so far it’s been trouble free.
If you regularly use it, (I do) then just install an Anderson connector and plug it in when you need to. They are polarized so you don't plug it in backwards, and nicely insulated so they don't short out when not in use.
 
I read about top balancing the batteries before first use. I didn't have a bench PS so I bought an inexpensive one on AZ that produces 10A up to 30V. I saw someone had hooked up a similar PS and they did one battery at a time and then the whole bank. I hooked it up to the first battery and set it to 3.55V. After two days it had only brought the battery from 3.3V to 3.4V. Then I tried to connect to a second battery. Doing it the same way, as soon as I connect the battery the PS goes from constant voltage to constant amperage. I can't get the PS to operate in CV mode now.

Reading the directions was a bit interesting as they have you plug the PS in the wall but they never mention connecting to the battery :) BTW, the instructions I followed said to turn up the CA dials to max and then turn the CV dials to the voltage I want. That is fine, but the charger jumps to 10A CA as soon as the battery is connected. Even for a brief amount of time, it seems the wires would melt. Not really suited for 10A current.

Mine is the Dr. Meter brand mentioned here and appears to be the same model like the one shown in the YouTube picture. As mentioned, it seems there are a lot of similar PSs that just have a different name on the cabinet.

Thanks for any help on either getting the batteries top balanced or getting the PS to work according to the instructions.
 
@Just John Thank you for your testing, and thank you for the power supply recommendation. I'm building my first solar system and need something to top-balance my incoming Eve cells. This is perfect, just ordered one.
 
I read about top balancing the batteries before first use. I didn't have a bench PS so I bought an inexpensive one on AZ that produces 10A up to 30V. I saw someone had hooked up a similar PS and they did one battery at a time and then the whole bank. I hooked it up to the first battery and set it to 3.55V. After two days it had only brought the battery from 3.3V to 3.4V. Then I tried to connect to a second battery. Doing it the same way, as soon as I connect the battery the PS goes from constant voltage to constant amperage. I can't get the PS to operate in CV mode now.

Reading the directions was a bit interesting as they have you plug the PS in the wall but they never mention connecting to the battery :) BTW, the instructions I followed said to turn up the CA dials to max and then turn the CV dials to the voltage I want. That is fine, but the charger jumps to 10A CA as soon as the battery is connected. Even for a brief amount of time, it seems the wires would melt. Not really suited for 10A current.

Mine is the Dr. Meter brand mentioned here and appears to be the same model like the one shown in the YouTube picture. As mentioned, it seems there are a lot of similar PSs that just have a different name on the cabinet.

Thanks for any help on either getting the batteries top balanced or getting the PS to work according to the instructions.
If the difference between the set voltage and the cell voltage is enough, it is totally normal for the power supply to jump straight to constant amps. The alligator clip leads that come with most supplies are generally poor quality and should be replaced or changed with better wires and connections.
 
You could use a shottky diode to force the energy in the battery to stay in the battery. This will also work for connecting 2 battery packs together that at different SOC, either for charging or for use in an Ebike or RV, etc.

Diode I ordered the SBR60A60CT these have one 30amp diode on each of the 2 outter legs and you will only need to use one for charging. You can combine both outer legs and get a 60amp diode with ultra low loss. You can dial up your PS voltage a little bit to compensate for the loss.
 
Would a double outlet charger reduce top balancing time by 50% if a 16 cell setup was split into two lots of 8 or would the two sets still need to be then reconfigured as one battery ?
 
I got the Longwei today as I always wanted a bench PS. But do I really need it? I don't know but I got it now...
for someone who hasn't used one what can I experiment with on it to familiarize its features to me?? I want to get good with it so it will be useful..
 
Back
Top