switchboards

n.

电话总机，电话交换台( switchboard的名词复数 )；

telephone switchboard电话交换台，电话交换机

switchboard operator接线员

SWITCHBOARDS
Switchboards :
Credentialed Secure Communication "Switchboards"
Noncommutative Schur functions, switchboards, and Schur positivity
The Behavior of Arcing Faults in Low-Voltage Switchboards
The behavior of arcing faults in low voltage switchboards
Determination of the Cause of Arcing Faults in Low-Voltage Switchboards
Determination of the cause of arcing faults in low voltage switchboards
Monitoring the competitiveness in the supply of low-voltage switchboards
IEEE Recommended Practice for Electrical Installations on Shipboard -- AC Switchboards