SMA SC 500HE-US Installation - Manual (Page 15)

SMA America, LLC 2 Safety
Installation Manual SC500HEUS-IA-US_en-14 15
Any other application of the Sunny Central or installation of components and modifications which are
not explicitly allowed endanger the safety and void the warranty as well as the operation permit.
PV and AC disconnect
As an option, the internal AC circuit breaker of the Sunny Central can be mounted externally either in
the Disconnect Unit made by SMA or in another cabinet provided by others.
Disclaimer
• It is prohibited to use the Sunny Central for purposes other than those described here.
• It is prohibited to modify the Sunny Central or to install components that are not explicitly
recommended by SMA or sold by SMA for this purpose.
• It is prohibited to connect the Sunny Central without transformer to the grid. Operating the
Sunny Central without transformer causes a short-circuit and can destroy the Sunny Central.
Position Description
A PV modules
B DC distribution with DC fuses (e.g., Sunny Central String-Monitor)
C e. g. SMA Disconnect Unit
D Sunny Central
E e. g. SMA Disconnect Unit
F Transformer
G Public grid
The unit is provided with a UL listed circuit breaker on the output rated 1600 A for branch circuit
protection. If the circuit breaker shall be located externally to secure the AC path, you have to
use the same type of circuit breaker (ABB Emax E2B-A with 42 kA rated short-circuit current,
ABB Emax E2N-A with 65 kA rated short-circuit current or ABB Emax E2H-A with 85 kA rated
short-circuit current and and 1600 A continuous current rating each) to ensure UL listing of the
whole system.
According to National Electrical Code
®
ANSI/NFPA 70 and Canadian Electrical Code it is
neccessary to install a PV and AC disconnect. Therefore, either the Disconnect Unit made by
SMA for PV as well as AC disconnection or a solution provided by others has to be used to
satisfy this requirement.