Islanding breaker open flag

This signature is a read-only boolean status point that reports the position of the islanding breaker on the site controller. A value of 1 means the islanding breaker is closed and the system is connected to the grid. A value of 0 means the islanding breaker is open and the system is running off-grid, which is the pattern to look for when islanding is reported. Over Modbus, the point is read from register 29025 as a single int16 value. An open breaker can also come from a deliberate command: a user can write the Intentional Island point to open the islanding breaker. Before treating an off-grid reading as unexpected, check the Intentional Island setpoint and its feedback point.

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• sentence 3: support check: partial - 0 = breaker open, off-grid is stated, but the passages say nothing about it being the pattern to look for when islanding is reported.
• sentence 6: support check: partial - The setpoint and feedback points exist as user triggers to open the breaker, but the passages give no guidance to check them before treating an off-grid reading as unexpected. -->