BFL13 wrote:
Here we go again. A 22v max input MPPT???? You don't gain hardly anything with MPPT and 12v panels, so that's a waste of money. You can do that with a $13 PWM controller. But you do need MPPT for a 24v panel, but they have Voc more like 37v.
It is beyond stupid to have an MPPT controller that can only handle 22 Voc. Even a 12v PWM controller needs more than that. A 12v panel usually has 21.9-22ish Voc at 25C and it goes higher in cold temps.
Meanwhile if you have solar, who cares what the 7-pin is doing or not doing? The solar is working while going down the road too, so you already have extra amps from that.
This gizmo makes no sense at all.
I just asked the manufacturer for more detailed MPPT specs. They sell this mostly for the DC/DC battery charging feature so you can charge your trailer battery off the alternator without having to run heavy wire from alternator to trailer battery - very popular in Australia and Europe it seems. Maybe CTEK just "checked the box" on the MPPT feature.
"check the box" means to add a feature in name only, the actual effectiveness of the feature is not so important.
The fact that I can't find any real MPPT specs from CTEK is suspicious. Plus any
measured results by real users on internet forums that I have found have shown poor performance.
I'll post what the manufacturer responds with.
Ed
