Safe brake control function (SBC) prevents accidental hoist slipping and thus helps protecting people and the load. Safe direction function (SDI) ensures that the hoist can only move in selected safe direction. It helps prevent lifting too heavy loads and can also be used to let the operator bring material to a defined danger area.
Hoist movement information from a motor encoder is constantly required for detecting the load speed even when modulation is stopped. The pulse encoder interface module FSE-31 can be used for this purpose. When combined with safety functions module FSO-21 it enables building certified safety functions for hoisting movements.
The slowdown areas and end limits of long travel and trolley movements typically apply also for hoisting. Safely limited speed (SLS) function is used in slowdown areas, and safe stop 1 (SS1) function together with SBC for the end limits. SBC ensures that the brake is on after activation of SS1 function. The SCB function also always activates together with safe torque off (STO). This ensures safe control of hoist holding brake in the torque-free state.
The SDI function makes sure that the hoist can move only in one selected direction. It can be used in hoisting to prevent crane breakage by stopping lifting too heavy loads. This is realized by combining overweight detection and SDI functionality of FSO-21. Another typical use of the SDI function is to let the operator enter a defined danger area by ensuring that the hoist can only move in a safe direction.
- AC motors for the hoist movement
- Motor shaft encoder
- ACS880 drive
- FSE-31 pulse encoder interface module
- FSO-21 safety functions module add-on for the drive