What is different between PBX and EPABX?

Answer 1

PBX is what interlink all the phone lines or extensions within a building or office and connect it to the PSTN. The system will automatically select available line for outgoing call. EPBX on the other hand does not have any difference with the PBX system. The term PBX has just evolve from the the term EPBX and is highly recognized globally.

Answer 2

PBX - Private Branch eXchange

ePABX - Electronic Private Automatic Branch eXchange

Both are phone system types that make use of different method or concept in managing the communication of any business.