Which benefits do soft starters bring? (part 4)
Continued from the article: Which benefits do soft starters bring? (part 3)
The traditional method of achieving this protection was via a mechanical shear pin that consisted of a pin of a deliberately weak material inserted into two concentric shafts at a convenient point in the drive train to the load.
With this traditional way, iff the load became jammed, the sudden rise in torque would cause the pin to shear so that the two shafts could then rotate independently, thereby disconnecting the motor from its load. Before the load could be restarted, the old pin would need to be removed and a new one inserted - an obviously inconvenient and time-consuming process.
The electronic shear pin facility eliminates the need for a mechanical shear pin entirely because the speed and extent of a sudden and rapid rise in motor torque is immediately detected which will then decide on a course of actions ranging from instantaneous shutdown to monitoring for recurrences if the blockage is released rapidly.
Soft starters provide an electronic solution to mechanical problems at relatively low cost. They can extend the life of belts, chains, gearboxes, shafts, bearings and machine mountings.
In addition, soft starters can achieve real savings in energy for users by providing the facility to switch motors off, without fears for their restarting. Added to these factors, soft starters ensure security of operation even in the most critical of tasks.
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