塞尔维亚采购需求：直线执行器、直线电机、微型直线执行器、电动直线执行器、微型直线执行器、伸缩式直线执行器

I'm looking for a custom lifting column for a professional camera studio rig. It needs to be a high-quality, stable unit that can be mounted upside-down from a motorized ceiling rail, capable of supporting a DSLR camera rig weighing around 3 kg. My primary concerns are stability and speed during horizontal movement, so I'd like a quote for the column, matching controller, and handset. Can the column guarantee safety for inverted installation with a robust self-locking mechanism to prevent downward movement when power is off? I'm also interested in tight internal tolerances to minimize shaking when the trolley stops suddenly. What's the max speed this column can reach under light load, aiming for around 30-40mm/s? Additionally, can you provide dual Hall sensors to program memory positions? I need it to operate at 24V DC with a 3-stage rectangular profile. Please include the total price and the weight of the column.