Yingli Solar PV Modules, Installation and User Manual
page 5
Installation of grounding lugs must be in accordance with the specified
instructions of the respective manufacturers. A grounding lug must be attached
at a designated grounding hole location using #10 stainless steel hardware.
A stainless steel toothed lock washer or KEPS nut is required to adequately
engage the frame and penetrate the nonconductive coating. The screw holding
the appropriately sized EGC in place must firmly clamp the EGC in order to
establish a reliable electrical bond.
Figure 8: Grounding lug detail
Option B: Screw Assembly
1. A grounding screw assembly must be attached at a designated grounding hole
location using only stainless steel hardware. Insert a #10 stainless steel screw
first through the stainless steel cup washer, and then through the grounding
hole.
2. Loosely engage a stainless steel backing nut and toothed lock washer to the
screw.
3. Bend the EGC into an omega (Ω) shape to tightly fit between the partially
installed screw head and cup washer. The EGC shall be exclusively in contact
with stainless steel.
4. Tighten the screw to 35 in-lbf (4 N∙m) torque. The toothed lock washer
should be visibly engaged to the frame.
5. Route the appropriately sized EGC in such a way as to avoid contact with the
aluminum module frame.
Figure 9: Grounding screw assembly detail
Option C: Racking Manufacturer Integrated
Grounding Methods
Yingli Solar PV modules can be grounded by bonding PV modules to a grounded
racking system. Integrated grounding methods must be certified to UL 1703 or
2703 for grounding PV modules and must be installed in accordance with the
specified instructions of their respective manufacturers.
A.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.
B.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.
M E C H A N I C A L I N S TA L L AT I O N
Mounting structures and other mechanical parts must be designed and approved
to withstand the design wind and snow loads applicable for a particular site.
Yingli Solar PV modules must not be subjected to forces from the substructure,
including forces caused by thermal expansion.
The mounting method must not result in the direct contact of dissimilar
metals with the aluminum frame of the PV module that will result
in galvanic corrosion. An addendum to UL 1703 recommends metal
combinations not exceed an electrochemical potential difference of
0.5 Volts.
Yingli Solar PV modules can be mounted in landscape or portrait orientation, as
illustrated in Figure 10, provided that the mounting method follows one of the
acceptable methods listed below.
Figure 10: Landscape and portrait mounting
In order to maintain the fire class rating, the distance between the PV module
bottom surface and the roof surface shall be at least 2.48 inches (6.3 cm). This
spacing also allows air flow to cool the PV module. Install PV modules with a
minimum spacing of 0.4 inches (1 cm) between neighboring frames to allow for
thermal expansion.
Mounting Methods
The PV module is considered to be in compliance with UL 1703 only when the
PV module is mounted in the manner specified by the mounting instructions PV
module below.
Option A: Bolts or clamps
Refer to the Module Supplement at the end of this manual to determine how
many connection points are required for a specific module series. The locations
of mounting holes and clamp tolerances are illustrated in the drawings located
in the Module Supplement. Do not modify the existing mounting holes or drill
new holes. The minimum tightening force of the following mounting methods
are both 4N.m.
Landscape Orientation
Portrait Orientation
PV Laminate
Backing Nut
Toothed Lock Washer or KEPS Nut
Cup Washer
Aluminum
Frame
Screw
Equipment
Grounding
Conductor
PV Laminate
Backing Nut
Toothed Lock Washer or KEPS Nut
Grounding Lug
Equipment
Grounding
Conductor
Aluminum
Frame
Screw