Solar Controller (cheap china)

mena661 wrote:
I don't know what the issue is with using the cheap controllers. If they're working properly then that's all that matters. I'm gonna try out that Eco-worthy MPPT unit whenever I get my solar done.

I agree with this. However, one must first know the specs of the unit to know if it ever has a chance of working properly. For example, I want the ability to use a 14.8v set point with my 6v batteries, I want remote temperature compensation and I want equalization. My batteries rely 100% on solar for their charging. No connection to chassis charging system, never on shore or jenny power. So to ensure I get the longest life possible out of my batteries I want a charge controller that is not going to

- routinely undercharge batteries
- allow stratification and sulfation to run amok
- over or undercharge due to temperature fluctuations

If a $1 Chinese controller will do those things for me, I'll buy it (and monitor it closely). Trouble is, I've never found a single cheap Chinese controller that would even allow a 14.8v set point, let alone provide remote temperature compensation. I care about the specs more than the brand or price.

These are the specs listed for the controller that is the subject of this thread (near as I can tell - looks like the same one):

Output Voltage: 12V/24V Automatically distinguish voltage
Max load Current:=15A
Full Charge Cut:13.7V/27.4V
Low Voltage Cut:10.5V/21V
Temp compensation:-3mv/?/cell
Zero Load Loses:=20mA
Min Wire Size:=20mA
Min Wire Size:2.5mm^2
Voltage Drop:<210mv
Dimension: 101*95*35

"Full Charge Cut" makes it sound like an on/off controller, but elsewhere it claims to be PWM. So I assume the 13.7v is float voltage. No mention of absorption set point. No mention of equalization. That's the problem with some of these super cheap listings - not enough information to make an informed decision.

Will it charge batteries? Yes, I'm sure it will. But my question is will it charge them well, or will it, over time, damage my batteries and shorten their lives? It's not worth it to cut corners on the specs for me. It will end up costing more in the long run due to shortened battery life.