Grounding Methods - SCHOTT Solar Photovoltaic Modules Installation And User Manual

2.2

Grounding Methods

1) Grounding Lug with Thread-Cutting Screw at Grounding Hole
~20
in-lbs
copper wire
#4-6 at 35 in-lbs
#8 at 25 in-lbs
#10-14 at 20 in-lbs
2) Grounding Lug with Machine Screw at Grounding Hole
~20
in-lbs
copper wire
#4-6 at 35 in-lbs
#8 at 25 in-lbs
#10-14 at 20 in-lbs
module frame
SS #10 External Serrated Washer
(e.g. McMaster 91120A140)
Lug
SS 10-32 X 1/2 Thread-Cutting Screw
(e.g. Fastenal 11112837)
SS 8-32 K-Lock Nut
(e.g. Fastenal 70922)
module frame
Lug
SS #8 Flat Washer
(e.g. Fastenal 71008)
SS 8-32 x 1 Machine Screw
(e.g. Fastenal 0170682)
Select a grounding lug listed for direct
burial and outdoor use (tin-plated, solid
copper lay-in lug with a stainless-steel set
screw) capable of accepting a 4-14
AWG copper conductor, e.g. ILSCO
GBL4-DBT, Burndy CL50-1TN.
To the grounding hole, secure the lug
with stainless steel hardware consisting of
a thread-forming/thread-cutting screw of
at least 32 threads per inch and an
external serrated washer. Tighten the
screw until serrated washer has
penetrated frame anodization,
approximately 20 in-lbs.
Select a grounding lug listed for direct
burial and outdoor use (tin-plated, solid
copper lay-in lug with a stainless-steel set
screw) capable of accepting a 4-14
AWG copper conductor, e.g. ILSCO
GBL4-DBT, Burndy CL50-1TN.
To the grounding hole, secure the lug
with stainless steel hardware consisting of
a machine screw (min#8), a flat washer,
and a lock nut, as shown in the figure.
Tighten the nut to approximately
20 in-lbs.
Tighten the lug set screw to the copper
wire at the torque specified by lug
manufacturer.
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