Pendant luminaires are luminaires which are suspended from (pendant-mounted on) the ceiling. Basically any luminaire can be pendant-mounted, be it an individual luminaire or part of a power track or wire and rod system, be it over a dining table, desk or workbench. Ceiling luminaires with light exit openings for indirect lighting (light emission upwards) need to be operated as pendant luminaires. They may be suspended by steel ropes, threaded rods or stem mountings; a luminaire must never be suspended by its connection cable. Adjustable systems – e.g. for dining table luminaires – allow the height of the suspended fitting to be varied.