6.5.1.2 The INS should be supplied：
.1 from both the main and the emergency source of electrical power with automated changeover through a local distribution board with provision to preclude inadvertent shutdown; and
.2 from a transitional source of electrical power for a duration of not less than 45 Sec.
6.5.2 Power interruptions and shutdown
6.5.2.1 After a power interruption full functionality of the INS should be available after recovery of all subsystems. The INS should not increase the recovery time of individual subsystem functions after power restoration.
6.5.2.2 If subjected to a power interruption the INS should, upon restoration of power, maintain the configuration in use and continue automated opertion, as far as practicable. Safety related automatic functions, should only be restored upon confirmation by the operator.
7 Interfacing
Interfacing to, and from, the INS should comply with International Standards*, as appropriate.
8 Fall-back arrangements
8.1 The INS should, after a failure, support the availability of essential information through the use of appropriate fallback arrangements.
8.2 Normal operation, after use of a fall-back arrangement, should only be restored upon confirmation by the operator.
* IEC 61162 Series
