Built for panel engineers

Sizing answers.
Code cited.

VoltForge helps engineers design industrial machine control panels with fast, traceable answers grounded in UL 508A and the National Electrical Code.

The toolkit

From panel inputs to a defensible next step.

Enter your panel and load specs, then get a clear recommendation with the rule behind it. No black boxes, no hunting through disconnected tables.

01Free

Motor & load sizing

Translate horsepower, voltage, and phase into defensible conductor, breaker, and motor starter recommendations.

NEC Articles 310 & 430 · UL 508A
04Free

Unit converter

Convert engineering units — length, area (incl. kcmil wire sizes), volume, weight, temperature, torque, pressure, and power — with the factor and math shown.

SI constants · NIST SP 811
05Free

Enclosure heat

Size cooling and heating from panel dimensions, mounting, material, and device heat loss — with formulas shown.

nVent Hoffman / Rittal sealed-enclosure method
06Free

Wire size from load amps

Enter a load current and get the smallest copper conductor gauge from the ampacity table, with the code citation behind it.

NEC Table 310.16 · 310.15(B)(16)
07Free

Amps ↔ kW

Convert between current and real power for single- and three-phase loads with power factor — formula and citation shown.

kW = V·I·PF·√3 ÷ 1000
08Free

Main disconnect & breaker

Size the panel main switch and main breaker from up to 10 three-phase motor and non-motor loads.

UL 508A §28 · NEC 430
09Free

Panel SCCR

Evaluate the panel's short-circuit current rating component-by-component per UL 508A Supplement SB and compare it with the available fault current.

UL 508A Supp. SB · NEC 409.110
10Free

Voltage drop

Size conductors so branch and feeder voltage drop stay within the 3% / 5% guidance, never below the Table 310.16 ampacity floor.

NEC 210.19(A)(1) · 215.2(A)(1)
12Free

Grounding & bonding

Size equipment grounding conductors and grounding electrode conductors from the table and code rules.

NEC 250.122 · 250.66
13Free

Ampacity derating

Apply ambient temperature and conductor-bundling adjustment factors to the base ampacity tables.

NEC 310.15(C)(1)
15Free

Control transformer

Size control-power transformers and their overcurrent protection for the control circuit load.

UL 508A §32 · NEC 430.72
17Free

Power factor correction

Calculate the capacitor kvar needed to bring a load to a target power factor.

IEEE Std 141 · NEMA MG 1
18Free

Cable tray & wireway fill

Check fill and spacing limits for cable tray and wireway installations.

NEC 392.22 · 376.22
20Free

Busbar sizing

Size panel busbars from continuous load and short-circuit withstand requirements.

UL 508A §32 · NEC 408.30
21Free

Panel label generator

Generate the field-marked nameplate and arc-flash warning label text for the panel.

NEC 409.110 · NFPA 70E 130.5
22Free

Resistor color code

Enter the resistance value you want and read back the IEC 60062 color bands — 4- or 5-band — with per-color counts and the tolerance range.

IEC 60062 (EIA RS-194)

Reference framework

Built around the standards you already use.

UL 508A
Industrial Control Panels
NEC 310 / 430
Conductors, motors & circuits
NEC Chapter 9
Raceways, fill & dimensions

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