MNDC Installation Instructions
Rev: New Page 3 of 7
Wiring diagram supplied on the door of MNDC
Grounding
There are various ground circuits that need to be considered in the renewable energy system. The
MNDC chassis should be grounded to your earth ground rod through a 6AWG wire connected to
the ground bus bar located in the top left section of the MNDC chassis. The MNDC ground bus
bar will then become your primary system DC ground. The ground bus bar is also where DC
lightning arrestors get grounded. It is advisable to use one of the ½” conduit knockouts to mount
a DC lightning arrestor to the MNDC box. It is also common to have a DC lightning arrestor out
at the PV Panels that are grounded through their own ground rod. In dry climates it is advisable
to also run a ground wire from the PV panels to the MNDC ground. The MNDC ground bus bar
is an ideal place to ground a DC-GFP when installed as well as the inverter chassis and the
charge control chassis. Do the grounds first since they normally lie in the bottom of the chassis.
Ground Bus Bar
