233.When does a class 3 failure have to be corrected ?

428.AC transfer enable AC buses:

427.DC BAT BUS can be supplied by the :

426.AC ESS BUS is normally supplied by the :

425.The static inverter operates

424.Where is the PTP located ?

423.What are the type A DEUs connected to ?

422.Where are the coding switches located ?

421.If the self-test of director 1 fails:

420.What happens if the DC essential bus fails ?

419.In normal operation director 1 is supplied by: