I picked up this part to charge a NiMH 7.2v Battery with my solar panel.

Has anyone used this module, or know where to get more information about how to use it?

I want to be able to take the 10v @ 500mA from my solar panels and volt and current limit to 7.2v @ 400mA to charge my NiMH 7.2v battery.

I think I can just adjust the 2 rightmost pots (current/voltage regulation) to accomplish this to charge my battery, but I'm confused as to what use the two pots on the left actually do. The notes don't explain their purpose to me very well.

My guess is the first pot just enables or disables the module, turned one way no output, turned another you get output.
I don't even have a guess as to why anyone would want to play with the lamp current.

Thanks!



https://www.ebay.com/p/5a-Step-down...l-MPPT-DIY/1876114221?iid=183708229591&chn=ps

 

Did they give you a schematic?

Have you got a link to instructions?

 

Did they give you a schematic?

Have you got a link to instructions?

Naw, but these little DC-DC MPPT circuits are on different sites. I've been looking for some documentation but so far nothing. I just thought maybe this was a standard circuit someone here might recognize. Apparently, it's not a true MPPT, but I think that's just because it doesn't track voltage to output, rather you set a pre-defined output.

It would be good enough for my purposes, I just have no idea why they bother with the lamp control. The MPPT pot seems to be just to vary the degree of incoming allowed voltage - or maybe incoming power, not sure if it has anything to do with the current.

 

I believe the first thing I would do, is find out more information. I would look on ebay and amazon for similar items.......the ones with answered questions and reviews. Many times in the questions and reviews.......they post links to further information.

 

From what i can gather, it has three modes, Constant Current, Constant Voltage for chargers, and Hi Led driver current facility, the Lamp pot is to set Minimum current detection for the Red/Green led.

 

From what i can gather, it has three modes, Constant Current, Constant Voltage for chargers, and Hi Led driver current facility, the Lamp pot is to set Minimum current detection for the Red/Green led.

Oh ok, that makes sense. So if I put a battery on it I adjust the light to display green when full, but red when charging based on current draw. Charging batteries are probably the most used case for this thing.

 

MPPT is abused and misused about the same as HIFI

 

MPPT is abused and misused about the same as HIFI

That seems to be what I'm finding out. MPPT is listed everywhere on devices, then you find out they mean PWM. I'm sure this little device is not a true MPPT. It's labeled MTTP in the picture haha so im not sure what that tells us.