Crane Control Commands: Hoist, Trolley and Bridge Motion Directions

Understand hoist up/down, trolley and bridge commands, two-step pushbuttons, emergency stop, direction marking and commissioning checks.

How basic motions differ

Hoist up/down moves the load vertically. Trolley travel moves the hoist along the bridge, while bridge travel moves the complete bridge along the runway. Jib systems may also include slewing.

• Hoist
• Trolley
• Bridge
• Slewing

What two-step pushbuttons do

Depending on system configuration, first and second pushbutton stages can command different speeds or control behaviour. Button function is linked to the panel and drive design.

• First step
• Second step
• Speed
• Drive

When motion directions are checked

After installation, motor/panel work or changes to phase connections, command direction versus actual motion is part of commissioning verification.

• Command/direction match
• Installation
• Panel work
• Commissioning

Emergency stop and access

Emergency-stop function, control access and operator authorization belong in the site safe-work procedure. Control markings should remain readable and match actual equipment motion.

• Emergency stop
• Authorization
• Marking
• Safe operation