SMA Sunny Island 2012 Technical Description page 153

SMA Solar Technology AG
Relay configuration
You can only assign one function to each relay.
Operating principles of the relays
The relays are changeover contacts. They can be used as normally closed or as normally
open contacts.
The relay functions are listed as NO contact functions, in other words, the contact is
closed if the relay is activated by selecting the function.
The exception is the "Alm" (Alarm) relay function. Here, the relay is a NOC. Normally,
the relay is activated, and the contact is open. In presence of a fault, the relay is
deactivated, the contact closes and in so doing switches on, for example, a fault indicator
light.
Relays in fault situations
In case of failure the relays change to safe state, i.e., they are deactivated.
Technical Description SI2012_2224-TEN082311
Relay
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