CPS SCA Series, Инструкция по установке и эксплуатации

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2.7 Anti-Islanding Detection
The SCA25KTL-DO/US-208
、
SCA50KTL-DO/US-480 and SCA60KTL- DO
/US-480 3-Phase String Inverters include Unintentional Islanding detection
as required by UL 1741/IEEE 1547. The inverter will continuously make
bi-directional perturbations to the frequency of the output current by injecting
a small amount of reactive power to detect a possible islanding condition. If
the grid is stable, these small perturbations will have negligible effects on the
system voltage frequency. However, in an islanded condition the changes in
reactive power will force the frequency of the system voltage to deviate
significantly, which will trigger the inverter to cease operation and disconnect
from the grid.
2.8 DC Ground Fault Protection
The inverters include residual current detection GFCI as part of the DC
ground fault detection method required by UL 1741. If there is a ground fault
in the PV array, the ground fault detection circuitry will detect leakage current,
trigger an alarm, and the inverter will cease operation. See Chapter 5 for
further information regarding GFCI Static and Dynamic trip thresholds and
operation.
2.9 Surge Suppression
Table 2-1 Standard Waveform Peak Values
Standard Waveform Peak Values
Surge Category Ring Wave Combination Wave
B 6kV/0.5kA 6kV/3kA
 "Standard 1.2/50 μs - 8/20 us Combination Wave"
 "Standard 0.5 μs - 100 kHz Ring Wave"