INSTALLATION AND OPERATION MANUAL SOLAR MODULES Q.PEAK DUO XL-G11S.X / BFG
14
2 Planning
2.4 Electrical layout
Module Selection
For detailed key electrical data, please refer to the actual data
sheet referring to the relevant Module (available at www.qcells.
com).
For maximum energy yields, mismatches of specified electric
current (I
MPP
) of more than 5 % should be avoided for all mod-
ules connected in series.
Safety Factor
During normal operation, a module may generate a greater cur-
rent and / or higher voltage than that determined under standard-
ized test conditions. Accordingly, the values of I
SC
and V
OC
marked
on the module should be multiplied by a facot of 1.25 when de-
termining:
■
the component voltage ratings,
■
conductor ampacities,
■
fuse sizes,
■
size of controls connected to the PV output.
Refer to Section 690-8 of the National Electrical Code for an
additional multiplying factor of 125 percent (80 percent derating)
which might be applicable.
Please follow the valid national guidelines for the installation of
electrical systems (refer to section 690-8 of the NEC for an ad-
ditional multiplying factor of 125 percent [80 percent derating]
which may be applicable).
Series Connection
Connection of modules in series is only permitted up to the maxi-
mum system voltage as listed in the applicable data sheet.
Take into account all possible operating situations and all rel-
evant technical norms and regulations when designing the
system. It has to be ensured that the maximum system voltage,
including all necessary safety margins, is not exceeded.
Take the voltage limit of the inverter into account when deter-
mining the maximum number of modules in the string.
Parallel Connection
Modules may be damaged by the occurrence of reverse currents
(caused by module defects, ground leaks, or defective insulation).
Ensure that the maximum reverse current load capacity indicat-
ed in the data sheet is met.
In order to limit reverse currents that may occur, we recommend
using the following safety options:
1) Layout with a limited number of parallel connected strings :
Without undertaking further current blocking measures, a maxi-
mum of two module strings may be operated in parallel on a sin-
gle inverter or MPP tracker.
2) Layout with string fuses :
Use overcurrent devices (e.g. fuses) according to the relevant
standards in each string. Use gPV-fuses according to IEC 60269-
6. Observe the maximum permitted number of strings as indicat-
ed in the specifications provided by the respective string fuse
manufacturer and the technical guidelines.
NOTE!
When installing different product versions, the lowest minimum
permitted reverse current load capacity applies.
Inverters
Inverters with or without transformers may be used.
