Can somebody please explain the purpose of the NEMA TT-30 port? Is the NEMA port to charge or discharge? I was originally under the impression that I would be able to charge the AC200max at an RV campground by connecting the campsite power to the NEMA port. Now I’m wondering if that is a discharge port and not usable for charging from a campground power source. Please advise… thanks in advance.
@Speakpixie You are correct. That NEMA TT-30 is a output only plug on the ac200max. Meaning you plug your camper/rv “shore line” into it. It acts as the pedestal at a campground to power/charge your camper.
You could use the supplied power brick that came with the Max and plug it into the actual pedestal at the campground to then plug into the dc7909 input on the Max to charge it up.
As has been explained, the NEMA TT-30 outlet is an output port only 
. Typically, RVs / campers / trailers come with an RV-30 shoreline cable for connecting to electrical power at RV Parks .
Have connected electrical power to RV by plugging the RV-30 shoreline cable to the NEMA TT-30 outlet of the AC200MAX . Used an appropiately sized extensions cable to connect the RV-30 shoreline cable to the AC200MAX NEMA TT-30 outlet inside RV
The RV-30, or NEMA TT-30, refers to 30 Amps use