MODULAR SUNWAY TG
TE OD
INSTALLATION GUIDE
92/
139
Rev. 03
– 01/06//2018
9. DC INPUT COMPONENTS DIMENSIONING
9.1.
DC input fuses dimensioning
NOTE
The DC input fuses are to be ordered separately.
The DC inputs of the SUNWAY TG TE are fuse-protected both on the positive pole and on the negative
pole. The fuses status is detected by the control electronics and made available as equipment status info.
The fuses to be installed must be compatible with the type of fuse-holder used (please refer to section 8.16).
The configuration of the fuses installed on each input is given in the Final Test Certificate.
Figure 62: Fuse configuration example as in the Final Test Certificate
NOTE
The formulas below are given as an example and are to be checked based on the fuses being
used.
When designing utility-scale plants, it may be required that subfields having different power ratings are to
be configured for the same PV array. It is therefore advisable to protect each cable entry to the inverter with
fuses having different sizes. This section covers the criteria for the correct dimensioning of the input fuses.
The I
N
rated fuses are normally related to 30 °C ambient temperature. Apply A1 derating coefficient for
applications at higher ambient temperature.
The fuses are to be chosen in order to obtain:
𝐼
𝑁
≥
𝐼
𝑆𝐶
𝐴1
where
𝐴1 = √
130 − 𝑇
𝐼𝑁𝑇 𝑀𝐴𝑋
100
𝐼
𝑁
is the rated fuse current,
I
sc
is the maximum short-circuit current of the PV field portion connected to the
input in question, and T
INT MAX
is the maximum temperature internal to the cabinet attained during operation;
as initial approximation, this should be:
