Appendix G: Determining The Circuit Breaker Size; Using Transformers In Commercial Three Phase Inverter Installations - SolarEdge Delta SE12.5K Installation Manual

Appendix G: Determining the Circuit Breaker
Size
Inverters should be protected by circuit breakers. This document describes how to
determine which circuit breaker to use in three phase commercial installations.
Using Transformers in Commercial Three Phase
Inverter Installations
Using transformers in a commercial installation is optional. In most cases a transformer
is used to connect the installation to the medium voltage power grid. The following
figure illustrates a typical transformer and commercial three phase inverter installation
topology.
Figure 38: Typical transformer and commercial three phase inverter installation topology
There are many considerations for selecting the suitable transformer and its associated
current limiting devices such as circuit breakers and fuses. The considerations must
include at least the following:
The transformer should be designed for a typical PV system production profile: high
daytime loads with no loads at night.
Three Phase System MAN-01-00505-1.5

Appendix G: Determining the Circuit Breaker Size

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