7
EN
NL
F
R
DE
ES
SE
A
p
p
e
n
d
ix
3.3 PV connection
The PV input current of the charge controller is limited to 75A. In case of a potential
solar array output exceeding 75A, the solar array voltage will increase up to the level at
which the output is reduced to 75A.
The required PV cable cross section depends on array power and voltage. The table
below assumes that maximum PV power has been installed. Cable cross section can
be reduced in case of smaller solar arrays.
The best efficiency is reached at a PV input voltage that is twice the battery voltage.
DC circuit breakers or fuses must be installed in the positive and negative PV cables, to
enable isolation of the charger during installation or maintenance.
The table below gives some examples of cable cross sections calculated with formula
(5).
(in this case I and V are the output current and output voltage of the solar array)
12V system (solar array up to 1200W)
Solar array
MPP-voltage
[V]
Solar array
MPP-current
[A]
Power loss
in PV cables
α
(%)
Length 2x5 meter
Length 2x10 meter
Length 2x20
meter
mm
2
AWG
mm
2
AWG
mm
2
AWG
18
66
2
35
2
Not recommended
Not
recommended
36
33
1
16
5
35
2
Not
recommended
54
22
1
10
7
16
5
25
3
72
16
0,75
6
10
16
5
25
3
90
13
0,5
6
10
10
7
25
3
108
11
0,5
4
11
6
10
16
5
24V system (solar array up to 2400W)
Solar array
MPP-voltage
[V]
Solar array
MPP-current
[A]
Power loss
in PV cables
α
(%)
Length 2x5 meter
Length 2x10 meter
Length 2x20
meter
mm
2
AWG
mm
2
AWG
mm
2
AWG
36
66
1
35
2
Not recommended
Not
recommended
54
44
1
16
5
35
2
Not
recommended
72
33
0,75
16
5
25
3
35
2
90
27
0,5
16
5
25
3
35
2
108
22
0,5
10
7
16
5
35
2
The voltage on the PV input should never exceed 150V under any condition.
The charger will be permanently damaged if the input voltage is too high.
Cable strain relief must be provided, close to PV and battery connectors.
