|
Post by cybrmarc on Nov 5, 2019 18:09:10 GMT
Just switched to an MPPT controller from PWM (now have Renogy Rover 40Amp.) I'm trying to understand the amperage difference - I used to get 15amps on my shunt and now only get ~10 max) and wondering if one of my old solar panels died around the same time as I installed the new controller.
I do know that MPPT focuses on letting through more voltage and then converting that at some point to more amps. But both my shunt (between panels and controller) and the controller itself only get about 10amps max, whereas before my shunt that came just before my cheapo Chinese PWM controller showed 15+ amps.
Is the number the Rover giving me actually the "pre-converted" amperage at more than 12V? Because it doesn't have a number for what the battery is actually getting in 12V form, other than an amp-hours in number which seems to correspond to the Amps-in number I'm seeing over time. Am I missing something?
Setup is ~250 Watts panels on 2 12V batteries in parallel, total ah is 320. Thanks
|
|
|
Post by mediadogg on Nov 5, 2019 20:27:15 GMT
If you didn't measure both the current and the voltage (power), you can't compare based on the amperage alone. It is possible that you are getting the same amount of power.
|
|
|
Post by bupkis on Nov 5, 2019 20:55:10 GMT
I have no idea what amps the Rover displays (panel to controller or controller to battery).
If you are still set up with panels in parallel then the PWM controller would have the panels operate at battery voltage +/- while the MPPT controller forces the panels to operate @ MPP.
During Bulk charge (100% panel voltage being used) PWM operates 12-15v while MPPT operates @ 16-18v.
That said if you were seeing 15A while charging @14v or 210 watts you might now see 210/17v or 12A+ @ your shunt due to the voltage being higher. both deliver ~15A to the battery.
|
|