Выражение встречается в следующем контексте:
b) To select FO on remote test, place a shorting link between terminals C1 & C3.
i. To ensure FO is selected, check continuity between terminals C24 & C25.
ii. Ensure ship>shore and shore>ship ESD is healthy
iii. To check FO system is healthy, check continuity between terminals C22 & C23.

Заранее спасибо ВСЕМ!!