Electrical Engineering Calculators
14 electrical calculators in the Engineering Database. Each tool runs deterministic calculations against authoritative reference tables, so results trace back to source standards.
Battery DC System Sizing Calculator
Sizes stationary battery banks for substation and datacenter DC systems per IEEE 485. Determines number of cells, required capacity with temperature and aging corrections, selects a battery model from the reference table, calculates string voltage range, and sizes the battery charger.
Paid tierBusway Voltage Drop Calculator
Calculates voltage drop for busway/busduct installations per NEC 210.19 limits. Looks up manufacturer-specific R and X from the busway-specs table and applies distribution pattern factors for end-fed, center-fed, or uniformly distributed loads.
Free with sign-inDry-Type Transformer Sizing
Selects the next-size-up dry-type transformer for a given load and calculates partial-load losses, efficiency, heat output, secondary full-load amps, available fault current, and voltage regulation.
Free to useGenerator Sizing & Fuel Calculator
Sizes standby or prime diesel generators for a facility load with N/N+1/2N redundancy, altitude and temperature derating per NEMA MG1, fuel storage sizing per NFPA 110 (Level 1 / Level 2), and motor starting kVA verification.
Paid tierMotor Branch Circuit Sizing (NEC 430)
Sizes motor branch circuit components per NEC Article 430: conductor ampacity (430.22), overcurrent protection (430.52), overload relay settings (430.32), and feeder sizing for multiple motors (430.24/430.62).
Paid tierMotor Sizing & Electrical Specification
Looks up motor full-load current (NEC 430), efficiency, power factor, torque characteristics, and starting current for a given motor HP and voltage. Returns FLC at all standard voltages, locked-rotor current, and NEMA performance data.
Free to useNEC Cable Sizing & Voltage Drop
Sizes electrical conductors per NEC ampacity tables with ambient temperature and conduit fill derating. Calculates voltage drop, selects conduit size, and determines grounding conductor size.
Free to usePower Factor Correction — Capacitor Bank Sizing
Sizes capacitor banks for power factor correction. Calculates required kVAR, selects standard capacitor bank size, and determines current reduction and optional annual savings from PF penalty elimination.
Paid tierPUE Estimator
Estimates datacenter Power Usage Effectiveness (PUE) from IT load, UPS topology, cooling type, and distribution losses. Returns the PUE value with an industry category rating, a percentage breakdown of all facility loads, and annual energy / cost projections.
Paid tierRack Power Budget Calculator
Calculates total IT power, cooling, PDU capacity, breaker sizing, rack U consumption, and weight for datacenter rack deployments. Supports predefined server platforms (DGX, HGX, etc.) or custom power/RU inputs.
Paid tierShort Circuit & Arc Flash Calculator
Calculates available short circuit current at a point downstream of a transformer (accounting for cable impedance and X/R ratio) and IEEE 1584-2018 arc flash incident energy for PPE selection.
Paid tierSTS/ATS Transfer Switch Selection
Selects static or automatic transfer switches for critical power applications. Filters by device type, ampere rating, voltage, fault current, and manufacturer preference; returns top 3 candidates with loading percentage, heat output, kVA capacity, and cooling requirements.
Paid tierSubstation Grounding Grid Design — IEEE 80
Designs substation grounding grids per IEEE 80-2013. Calculates grid resistance (Sverak), ground potential rise, tolerable step and touch voltage limits, actual mesh and step voltages, and performs safety checks.
Paid tierUPS Sizing Calculator
Sizes UPS systems for datacenter and critical power installations. Determines unit count from redundancy scheme (N, N+1, 2N, 2N+1), selects the next available rating from the ups-sizing-data table, and calculates efficiency losses, heat dissipation, cooling load, and battery runtime.
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Browse dataCalculatorsDeterministic engineering calculatorsSizing, checking, and conversion tools that run against the reference tables. Inputs are code-compliant, outputs are traceable to the source standard.
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