According to the relevant provisions of IEC 61643-32 "Connecting to photovoltaic
devices surge protectors - selection and use of guidelines", whether for household or
outdoor photovoltaic power plants, it is necessary to ensure the implementation of
lightning protection measures for photovoltaic systems:
Fig
6
.
10
1
）
It is generally recommended to install lightning protection devices (such as lightning
rods / lightning protection belts and down conductors) to prevent lightning from hitting
the PV array.
2
）
Lightning protection devices and down-conductors and related equipment in
photovoltaic systems (including photovoltaic panels, inverters, cables, power
distribution equipment) should maintain a safe separation distance S.
Suggested value of S: According to the general 5 storey height (about 15m) building
roof, S takes 2.5m enough, this distance can be simplified according to the inverse
relationship of the floor height.
A. When the safety distance S is satisfied
:
The position
①③
of the figure should be equipped with a lightning protection module. In
general, it is recommended to install Type II in position
①
and Type I in position
③
.
B. When the safety and safety distance S is not met
:
In addition to position 3, Type I lightning protection module should be installed in Figure
①②④.
3
）
The lightning down conductor and the equipment ground wire eventually sink at a
total ground point, but the two cannot share the wire. That is, the equipment grounding
wire should be pulled separately, and the wire diameter requirement >6mm
²
when the
safety interval distance S is satisfied.
4
）
About the above lightning protection lightning receptor system related design
reference GB/T 21714.3-2015
.
Photovoltaic panel
Inverter
Distribution
Cabinet
SPD
Power grid
Lightning
protection device
Grounding bar
1
2
3
4
Total grounding point
L
ig
h
tn
in
g
d
o
w
n
th
e
li
n
e
Equipment ground wire
Lightning down the line
Safety
interval S
6.4 Connecting The Ground Cables
In this solar system all the unloaded metal components and cases should be connected to
the ground.
Single inverter need grounding over a PE point, multiple inverters need connect all the
inverter PE cable and solar panels shelves to the same grounding point to achieve
equipotential.
The grounding steps as following:
Take out the ground screw at the inverter bottom, connect the ground cables as
following figure.
Notice: 1.The machine is safely separated from the lightning protection and the distance
is as far as possible.
2.Do not expose Grounding terminal in the air and precaution for the rain.
3.When you lock the case ground screw, the torque force should be 60kgf·cm.
Fig
6
.
9
WARNING
23
24
The lightning protection measures for photovoltaic systems shall be
carried out in accordance with the corresponding national standards
and IEC standards. Otherwise, photovoltaic devices such as
components, inverters and power distribution facilities may be
damaged by lightning.
In this case, the company does not carry out warranty and assumes
any responsibility.
