This rating indicates how long the hoist can be operated continuously based on the below cycle, assuming continued operation for a short time span.
Intermittent Rating (Percent ED) new line. Number of Starts Per Hour
This rating indicates the ED percent (ratio of motor ON-to-OFF time) and max. number of starts per hour (how many times the motor is started up in one hour) for a hoist that is operated continuously based on the below cycle, assuming continued operation or repeated starts over a long time span.
In the case of single speed:
- Single Speed: 60%ED, 360 starts/hr
- Dual Speed: 40/20 %ED, 240/120 starts/hr
- Single Speed: 60min
- Dual Speed: 30/10min
- Total operation time applies to gears, bearings and other mechanical parts; consumable parts are not taken into consideration.
- The grade symbols are indentical to those of ISO4301. (Cranes and lifting appliance-Classification)
FEM Relation between ISO-and FEM-Denominations
The grade symbols are identical to those of FEM 9.511. (Rules for Design of Serial Lifting Equipment: Classification of Mechanisms)