Question about solar charge controller.

[Dh1288]

Question about solar charge controller?
I live off grid with a Magnum MS4024 and just added lithium Iron Phosphate battery from Big Battery. I am a just now ready to add solar panels and I am debating whether it is necessary to go with the Magnum PT-100 as I have very little experience and it may be easier to set up with my inverter or get the growatt 80 amp solar charge controller that is more than 1/3 the price of the magnum unit. I will need two units to support my panels as I will have 20- 250watt panels on a 24 volt system . Any advice is appreciated!

 

[snoobler]

It really depends on if your ecosystem can meaningfully benefit from the Magnum ecosystem. If it's just maintaining the same brand, it's not particularly important.

While Growatt and their class are less expensive, consider that you are accustomed to the reliability of a Magnum unit as opposed to cheap Chinese stuff. Products on the Magnum level are ones you EXPECT to last for decades. Products on the Growatt level are ones you HOPE last 5+ years.

There are other options. 2X Outback FM-80 are only a little more than 1 PT-100. That should permit you to extract near peak power from the arrays.

2X Victron 150/85 are about 1.5X the price of a PT-100, but they also have low temperature charging protection.

I guess I'm just pointing out there are options between 2X growatt and 2X PT-100.

 

[Dh1288]

Thank you!

 

[snoobler]

Also want to re-emphasize that low-temp charging protection is very important. If you charge LFP below freezing, you destroy them. The only model I know for certain offers that option is Victron.

If they are stored inside and prevented from freezing, it's a non issue.

 

[Dh1288]

Thanks, yes I have them inside the cabin!