自动用户小交换机;［私用自动交换分机］ A private telephone exchange that automatically connects internal “branch” lines to the external circuits of a telephone system. 一种自动地将内部用户线连接到电话系统外线的专用电话交换机。 Private Automatic Branch eXchange的缩写h。
Private Automatic Branch eXchange的缩写。即自动用户小交换机，或者私用自动交换分机。 A private telephone exchange that automatically connects internal “branch” lines to the external circuits of a telephone system。一种自动地将内部用户线连接到电话系统外线的专用电话交换机。