Different Types of Motor Controllers and Torque Loads<\/strong><\/p>\n\n\n\n The core types of motor controllers are across the line motor starters, which come in full voltage non-reversing and full voltage reversing, soft start\/stop controllers, and VFDs.<\/p>\n\n\n\n Across the line, full voltage starters send full voltage, typically 480VAC, to the motor \u2013 usually with an accompanying \u201cclunk\u201d that can even dim the lights. Essentially, these motor starters go \u201cfull throttle\u201d as soon as they\u2019re turned on.<\/p>\n\n\n\n That issue is slightly alleviated by soft start\/stop motor controllers, which use a solid-state electronic device to ramp up the speed of the motor from 0 to 100% over a predetermined amount of time. It works the same way as it stops. This results in less wear and tear on the motor, but these still always go to full speed.<\/p>\n\n\n\n Finally, there are VFDs. Mountable in a motor control center or standalone, VFDs allow for the adjustment of motor speed over time, providing finer control while still realizing the benefits of less wear and tear on the motor.<\/p>\n\n\n\n There are also two central types of torque load. Constant torque loads exhibit roughly the same requirements, regardless of operating speed, while variable torque loads exhibit torque requirements that rapidly increase alongside machine speed.<\/p>\n\n\n\n In constant torque load applications, energy use is roughly proportional to speed. In variable torque load applications, energy savings aren\u2019t linear.<\/p>\n\n\n\n Applications, Such as Grain Handling, Benefits, and Cost Savings<\/strong><\/p>\n\n\n\n In comparing soft start\/stop controllers to VFDs, SS controllers are primarily used for energy savings and to prevent excess wear and tear on equipment.<\/p>\n\n\n\n However, in applications such as grain handling, VFDs provide those same benefits while also offering the ability to adjust speed as necessary.<\/p>\n\n\n\n Let\u2019s look at some scenarios to get a clearer picture.<\/p>\n\n\n\n Scenario #1: Run leg at a lower speed when no grain is present, then elevate to full speed when grain is in the pit prior to the leg.<\/strong><\/p>\n\n\n\n![\"Full](\"https:\/\/kasacontrols.com\/blog\/wp-content\/uploads\/2021\/04\/max-throttle.jpg\")
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