Translation guide
PBX refers to a private telephone exchange system used within an organization. In Japanese, it is commonly referred to using the English acronym or a descriptive term.
Referring to the telephone system that switches calls within a private organization.
The English acronym is widely understood in business and technical contexts in Japan. It is used as a loanword.
We installed a new PBX.
Adding システム (system) clarifies that you are referring to the PBX system, which is common in spoken and written Japanese.
The PBX system is down.
This is the formal Japanese term for PBX, often used in technical documentation or formal settings.
We need to change the settings of the PBX.