This is a placeholder topic for “Solar Power Manager For 12V Lead-Acid Battery” comments.
The DFRobot Solar Power Manager series are designed for IoT projects and renewable energy projects, providing safe and high-efficiency embedded solar power management…
Read moreHi,
I’m wondering if this is appropriate for use with the 12v 7ah lead acid batteries commonly used in alarm system applications? I see charging for 12v lead acid batteries at 4A quoted on the page but wanted to double check that is indicative of the charging capability of the device, not the maximum capacity for any attached battery?
Hi @Michael40079 - welcome to the forums 
That’s right, the charger will supply a maximum of 4A to any connected lead-acid battery. It’s up to you to decide if that current is appropriate for your use case.
4A might be a bit stiff for a 7AH battery, but of course, the wattage of your panel will ultimately determine the maximum charging current up to 4A rate.
Around 1-2A sounds appropriate for a 7AH battery.
I was wanting to use this device in a mini UPS configuration by substituting the solar input with an AC adapter.
Solar Panel/Adapter Charge IN (15~25V)
Initial testing was great until I fried it.
12VDC 3.33A - Meanwell MDR-40-12 - ok
12VDC 3A - Regulated Power Supply - ok - hardly any current draw
15VDC 3A - Regulated Power Supply - ok - cyclic current draw
24VDC 5A - Meanwell EDR-120-24 - RIP
It was ok until I noted a spot glowing on the board and quickly turned off but too late - it was free and let the smoke out.
I guess the lessons learnt are - read the datasheet, confirm and test in a measured way.
I am a novice and certainly learning from my mistakes.
In hindsight this line, “It is suitable for applications within 100W” is what I have overlooked as I was not going to being in that realm.
If the board had over current input protection to align with the 100W limit then I guess it would make it more idiot proof but I am sure I would have found another way to relieve it of its captured smoke.
Please suggest or recommend anything else I can learn from this.
Aaaah RIP! Sucks to hear @Tony134945 but it seems like you’re determined to squeeze the learning value out of the experience.
I think you’ve just about covered it - that 120W was 20W too many 
I agree that it’s curious the charger’s output isn’t limited, but we’re definitely outside the intended operation envelope here so i guess it’s to be expected.
Good on your for having a red hot (
) go.
You might find that this setup could be pretty hard on a power supply, because the Solar Manager could try to really draw as much power out of the PSU as possible, straining it and derating the output voltage. It’s hard to say but proceed with caution - the combination could reliably prove fatal for the PSU or the Solar Manger depending on configuration and loads. If you try it again I’d monitor the input and output voltage+current closely.
As an FYI, it was the input that killed it and not the load.
Features
For 18V Solar Panels within 100W
This is the only vague reference I could find.
I might email DFRobot and provide some feedback in the event it helps someone else
And you can get our latest projects and tips straight away by following us on:
