Z-bridge
In theater terms, a Z-bridge is a lighting bridge over the auditorium ( auditorium ).
function
Headlights are attached below the bridge . This Z-bridge can then be lowered for maintenance. The bridge was created because the pursuers (spotlights that are controlled by hand) were also positioned in the hall and therefore require a permanently accessible space. At concerts in larger concert halls or open-air stages, at the beginning, during the break or at the end of a show, you can watch the lighting technicians abseil down from these chase pulpits because the Z-bridges are missing here.
nature
The Z - bridge is open to the front and forms the shape of a Z with the ceiling. In classical theater this is movable. In many newer theaters these are rigid with access from the sides.
Web links
Z - Bridge on stagenine.info ( Memento from April 2, 2015 in the Internet Archive )