Data Center Electrical Calculator
Motor Starting Voltage Dip Calculator
Estimate the voltage dip at the point of common coupling during motor starting for DOL, star-delta, soft-starter and VFD starting methods.
Design Inputs
Results
Starting kVA
562.22 kVA
Estimated Voltage Dip
3.61%
Within the commonly-cited 10% general-purpose limit.
%Dip ≈ Starting kVA ÷ (Starting kVA + Source Fault Level), a simplified point-of-common-coupling estimate that ignores motor and cable impedance between the source and the motor. Acceptable dip limits vary by standard/utility (commonly 10–15% general purpose, much tighter for UPS-fed or sensitive loads) — confirm against the applicable code and the actual source impedance.
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