6
Figure 3.1
Module Ground Position
Junction Box
Label
Backside
The ground holes
are on the backside of
the module frame.
Ground Location
(larger holes for bolt and nut)
All
fasteners
(nuts,
bolts,
washers,
screws, etc.) must be stainless steel unless
otherwise specified.
Length of bolt should not be more than
0.78’’ (20 mm) in order to avoid
contacting the back-sheet of the module.
Acceptable grounding wire is following.
Ilsco Corp. GBL-4DBT 10-14AWG-Solid, 4-6,
8,
10-14AWG-Strand
Burndy L L C CL501TN 14AWG-Solid, 14-
4AWG-Strand
Tyco
Electronics
Corp.
1954381-
1/1954381-2 10-12AWG Solid
Each ledge on the module frame has two
larger holes for bolts (0.205’‘diameter
(5.2 mm)). These ground holes are
marked with a “G” or "ground mark"
adjacent to their location on the frame
rail (see Figure 3.1).
Ground wires must be connected to the
module’s metal frame at one of these
locations.
Lay-in lugs or grounding clips can be used
to ground Panasonic PV modules. Both
methods are explained below, please
choose one.
Grounding Locations (or grounding holes)
Using bolt and nut
(see Figures 3.3 and 3.5)
If using this method, use one of the larger
holes with diameter of 0.205’‘ (5.2 mm)
The bolt and nut size should be No.8
(0.164’‘diameter (4.16 mm)), or No.10
(0.190’‘diameter (4.83 mm)) or M5
(0.197’‘diameter (5.0 mm)).
Star washers must be used to make
contact through the anodization of
the module frame.
In this case, the screw threads are not
providing the electrical ground contact.
Recommended torque value in tightening
bolt and nut is 2.3 N.m (20in-lb).
Grounding Methods
Where common grounding hardware
(nuts, bolts, star washers, spilt-ring lock
washers, flat washers and the like) is used
to attach a listed grounding/bonding
device, the attachment must be made in
conformance with the grounding device
manufacturer's instructions.
Common hardware items such as nuts,
bolts, star washers, lock washers and the
like have not been evaluated for electrical
conductivity or for use as grounding
devices and should be used only for
maintaining mechanical connections and
holding electrical grounding devices in the
proper position for electrical conductivity.
Such devices, where supplied with the
module and evaluated through the
requirements in UL 1703, may be used for
grounding connections in accordance
with the instructions provided with the
module.
Wire connection using cup washers
(see
Figures 3.2)
The use of cup washers is to prevent wire
from slipping out from under the screw
head (and/or the flat washer).
Make sure that the cup washer is placed
between the wire and the module frame.
Choose an adequate size for the cup
washer and the flat washer so that the
wire is fully clamped between them.
Note: Cup washers are also called
terminal cup washers.
The cup washers should be stainless steel,
or a cup washer made of brass may be
used only if a large flat washer made of
stainless steel is inserted between the
module frame and the cup washer.
Choose the adequate size for the large
flat washer (between the module frame
and the cup washer) so that the cup
washer doesn’t contact the module frame
and is fixed stably to the module frame.
Method- Use a bolt and nut (see Figures 3.1
and 3.2)
If using this method, use one of the larger
holes with diameter of 0.205’‘ (5.2 mm)
The bolt and nut size should be No.8
(0.164’‘ diameter (4.16 mm)), or No.10
(0.190’‘ diameter (4.83 mm)) or M5
(0.197’‘ diameter (5.0 mm)).
Star washers must be used to make
contact through the anodization of the
module for this method.
In this case, the screw threads are not
providing the electrical ground contact.
Using a lay-in lug with bolt and nut
If using this method, please follow
instructions in previous section regarding
using
bolts
and
nuts
with
larger
grounding holes.
Use a grounding tin plated solid copper
lay-in lug rated for direct burial and
outdoor use. Lug must be used ILSCO
GBL-4DBT, BurndyCL501TN.
Attach grounding lug to module frame
using a stainless steel bolt and lock-nut as
shown in Figure 3.3.
Tighten stainless steel set screw at the
torque specified by lug manufacturer to
secure copper wire.
The specified torque is following
Ilsco
Corp.
GBL-4DBT
10-14AWG-Solid
->
20
in-lbs,
4-6AWG-Strand -> 35 in-lbs, 8AWG-
Strand -> 25 in-lbs, 10-14AWG-
Strand -> 20 in-lbs
Burndy L L C CL501TN 14AWG-Solid
->
35
in-lbs,
14AWG-Strand -> 35 in-lbs, 4AWG-
Strand -> 45 in-lbs
Recommended torque value in tightening
bolt and nut is 2.3 N.m (20in-lb).
Using a Grounding Clip with bolt and nut
Use
Tyco
Electronics
1954381-2
as
grounding clip.
As shown in Figure 3.4, place the
grounding clip onto the module frame.
Thread the hex nut onto the end of the
screw, then using a 3/8-in. wrench,
tighten
the
nut.
Recommended torque value in tightening
bolt and nut is between 1.7 and 2.2 Nm.
Insert the wire into the wire slot. Press
down on both ends of the wire.
Manually, or using channel lock pliers,
push the slider over the base until it
covers the base. This will terminate the
wire.
