Once the fuse failure condition is declared, it will be sealed-in until the cause that generated it disappears.

it will be sealed-in - ?
"будет герметизирован" - по контексту не подходит;
"замыкается" (в смысле, замыкается цепь, которую он разорвал) - тоже, вроде, ерунда получается: "Жучок - причина пожара".

На всякий случай, привожу текст до и после.

There are two classes of fuse failure that may occur: Class A: loss of one or two phases. Class B: loss of all three phases.
Different means of detection are required for each class. An indication of Class A failures is a significant level of negative sequence voltage, whereas an indication of class B failures is when positive sequence current is present and there is an insignificant amount of positive sequence voltage. These noted indications of fuse failure could also be present when faults are present on the system, so a means of detecting faults and inhibiting fuse failure declarations during these events is pro‐vided. ONCE THE FUSE FAILURE CONDITION IS DECLARED, IT WILL BE SEALED-IN UNTIL THE CAUSE THAT GENERATED IT DISAPPEARS.
An additional condition is introduced to inhibit a fuse failure declaration when the monitored circuit is de-energized; positive sequence voltage and current are both below threshold levels.