● Battery grounding: the charger can be installed in a positive or negative grounded system. Note: apply a single ground connection (preferably close to the battery) to prevent malfunctioning of the system. Is this referring to a central grounding point bus bar?● Chassis grounding: A separate earth path for the chassis ground is permitted because it is isolated from the positive and negative terminal. Does this mean that the B+ & B- terminals are isolated from the PV+ & PV- terminals on the MPPT allowing the B- terminal to be connected to the central grounding busbar?
● The USA National Electrical Code (NEC) requires the use of an external ground fault protection device (GFPD). These MPPT chargers do not have internal ground fault protection. Is this in reference to a GFPD located between the PV array and the MPPT?
The system electrical negative should be bonded through a GFPD to earth ground at one (and only one) location. What is meant by "system electrical negative", the battery terminal neg., the central ground to chassis, the PV-, or on the AC output side?● The charger must not be connected with grounded PV arrays (one ground connection only) Does this mean the PV- lead must not be grounded? That makes total sense to me BUT, how does this statement impact the installation of the DC-GFP MNDC-GFP63 GFPD as in the schematic below?
That may work, but if not, Can I isolate the battery bank neg. from the central grounding point?
It does seem a little complicated...