Detailed Description
Why Flat for Overhead Cranes?
EOT and bridge cranes travel along elevated runways. The main hoist and trolley move along the crane bridge girder, powered by a festoon cable system that must form consistent loops as the trolley traverses. Flat cable offers three specific advantages for this application:
- Loop stability: Flat cable loops remain in a single plane — no twisting, no loop inversion, no tangling — even when the trolley moves at 2–4 m/s
- Space efficiency: The crane bridge girder has limited space between the girder web and the festoon trolley track. Flat cable's thin cross-section fits where a round cable would need more clearance
- Visual inspection: A flat surface shows jacket damage immediately — round cable hides early wear between the helical turns
Construction and Steel Wire Messengers
The cable is built as a ribbon with parallel-laid cores: 0.6/1 kV power conductors in bare copper, IEC 60228 Class 5, from 1.5 to 50 mm², plus optional control conductors of 0.75-2.5 mm² in 2-12 cores. Core insulation is PVC or EPR.
Galvanized steel wire messengers at 1 770 N/mm² are vulcanized into both edges of the ribbon. They carry the mechanical load of the festoon loop, so the copper conductors see no tension as the loop opens and closes. The tensile safety factor on the steel messengers is 5:1 or better.
The outer jacket is PVC/CR or PVC/NBR compound in black - the cost-effective standard for indoor factory and warehouse overhead cranes.
Festoon Span and Drum Capacity
- Self-supporting festoon spans up to 40 m - no separate messenger wire to purchase or install
- The ribbon profile gives 30-50 % more cable per drum width than round cable of the same cross-section
- The smaller wound diameter allows a smaller festoon trolley and lighter loading on the crane boom
- Bend radius is 8 × cable thickness, for a compact loop in confined overhead crane girder space
Electrical Data and Options
| Item | Rating |
|---|---|
| Power cores | 0.6/1 kV; 1.5-50 mm² |
| Control cores | 300/500 V; 0.75-2.5 mm², 2-12 cores |
| Test voltage | 3 500 V (power); 2 000 V (control) |
| Temperature range | -15 °C to +70 °C |
| Flame retardant | IEC 60332-1-2 |
| Certifications | CE, RoHS |
Combining power and control cores in one flat cable removes a second cable run and a second set of terminations from the installation.
Applications
- EOT (electric overhead traveling) cranes - factory and assembly hall festoon cable
- Bridge cranes - warehouse and logistics centre overhead handling
- Workshop hoists and monorails - compact festoon for light-duty overhead lifting
- Jib crane power supply - rotating jib arm festoon or reel cable
- Indoor gantry cranes - light and medium-duty overhead handling