For safety reasons, manual switchboard
should provide protection against the effects of arc (minimum class AF) 16kA for a minimum of 1 second.
Call Center Comfort: Before there were cell phone towers there were manual switchboard
operators who worked at long distance call exchange centers.
On the hospital side, a manual switchboard
system left many callers aggravated because they couldn't get through quickly enough or to the appropriate departments.
The first automatic telephone switch that did not require manual operation was patented by Almon Strowger of Kansas City in 1891, but because of the perceived complexity of automatic circuit switching (and in some cases, simple inertia) manual switchboards
remained in common use in many places until the middle of the 20th century.
But she soon cooled when she discovered he had been brought in to automate the manual switchboards
and the operators decided to work to rule.