Soft Starters

A Soft Starter is an electronic device that gradually increases the voltage and current supplied to a motor during start-up, preventing sudden jolts and excessive power surges. Unlike Variable Frequency Drives (VFDs), soft starters do not control motor speed during operation but focus solely on smooth acceleration and deceleration. This makes them ideal for applications requiring reduced mechanical wear, energy savings, and minimized electrical grid disturbances.

Key Features of Schneider Soft Starters

• Gradual Ramp-Up: Eliminate inrush current spikes (up to 600% reduction) to protect motors and reduce grid stress.
• Torque Control: Adjust starting torque to match load requirements, preventing belt slippage or gear damage.
• Soft Stop Function: Gradually decelerate motors to avoid water hammer in pumps or product spillage in conveyors.
• Compact Design: Space-saving installation with DIN rail or panel-mount options.
• Advanced Protection: Safeguard motors from overloads, phase loss, overheating, and voltage imbalances.

How Soft Starters Work

• Controlled Start: Use thyristors (SCRs) to gradually increase voltage/current during motor acceleration.
• Peak Current Reduction: Limit inrush current to 2–4x full-load current (vs. 6–8x with direct-on-line starts).
• Soft Stop: Gradually decrease voltage to avoid mechanical shocks during shutdown.

Key Benefits

• Reduced Mechanical Stress: Smooth acceleration prolongs motor and driven equipment lifespan.
• Lower Operational Costs: Decrease energy bills and minimize downtime from equipment failure.
• Grid Protection: Prevent voltage dips and disruptions in sensitive electrical networks.
• Flexibility: Adjustable start/stop times and torque limits for diverse applications.