Specifications

V97-600002 Page 10 of 31
2.3.3 Grounding
A single-point ground connection is located in the lower right-hand side of the
inverter cabinet. This is where the PV array grounding wire is terminated. The AC
ground connection is terminated next to the Line 1 and Line 2 connections on the
circuit board.
The PV ground connector is attached to the cabinet with a 10-32 bolt. This ground
lug is provided to allow for the PV safety ground to be bonded to the cabinet. This is
the only place the ground should be connected to the inverter.
• Do not tie the safety ground to the PV array positive or negative. That would
defeat the ground fault protection circuit. (Refer to Figure 5.)
• See Table 2.3 for appropriate sizing of the grounding electrode. Use the
maximum current AC or DC - whichever is larger - and multiply it by 1.25 to
get the maximum current rating per NEC 690.
Maximum
current
rating
Minimum size of grounding
electrode conductor AWG
Copper Aluminum
Copper clad
15 8 6
20 8 6
30 8 6
40 8 6
60 8 6
Table 2.3 Grounding Electrode Sizing
Figure 4 is a schematic representation of the PV Powered single-point grounding. The
front cover is grounded through the cover mounting screws.
Line
Filter
Control pcb
Power Distribution PCB
DC
Power
Supply
L1
L2
GND
PV GND
20 A SB
System Block Diagram
120/240 VAC
60Hz
PV
DC input
+
GND
1A
GF Detect Circuit
-
Figure 4: System Block Diagram showing single-point ground