General information

Electrician Calculator Pro - National Electric Code (NEC) compliant calculator for electricians, engineers and electrical professionals, electrical contractors, designers, lighting experts, inspectors, maintenance personnel and builders!


Compliant with NEC 2020, 2017, 2014, 2011, 2008, 2005 and 2002, and future updates are FREE!

Visit our website for more details: http://www.ElectricianCalculator.com/


Forget about complicated key combinations normally required for NEC calculators! With this app you'll be able to perform the following calculations in a straightforward way:


• Voltage Drop
All voltage drop calculations use NEC chapter 9 table 8 values (either stranded or unstranded), and ambient temperature is taken into consideration as per NEC chapter 9 table 8 FPN 2.

• Find voltage drop (in volts and percentage).
• Find the maximum cable length given a required voltage drop and wire gauge (for single and three phase circuits).
• Find the minimum wire gauge given a required voltage drop and distance (for single and three phase circuits).


• Ampacity
Ampacity calculations use NEC tables 310.16 and 310.17 to find maximum ampacity or minimum wire gauge. The correction factor for temperature is used in these calculations.

• Find the minimum wire gauge given an amps value and ambient temperature (can specify if it will be in a raceway or free air).
• Find the maximum ampacity of a cable given its gauge, the ambient temperature, and if it is in a raceway or free air.


• Conduit sizing and conduit fill
Conduit and cable diameters are obtained from the tables in NEC chapter 9. Maximum fill percentages are obtained from NEC chapter 9 table 1.

• Find the minimum size conduit given the gauge and number of cables.
- Can specify the following conduit types: EMT, ENT, FMC, IMC, LFNB, LFNA, RMC, PVC-80, PVC-40 / HDPE, PVC-A, PVC-EB.
- Can specify the following insulation types: THHN, THWN, THWN-2, THW, THHW, THW-2, TW, XHH, XHHW, XHHW-2, RHH, RHW, RHW-2.
• Find the maximum amount of cables that can be used, given conduit size and type, and cable gauge and insulation.


• Motor full load current
Motor full load current values are obtained from NEC tables 430-247, 430-248, 430-250 in chapter 9.

• Find the motor full current load for DC motors, single phase, squirrel cage, wound rotor, and synchronous electrical motors from 1/4HP to 200 HP.


• Grounding conductor
Find the grounding conductor for service entrances and equipment, as per NEC tables 250-66 and 250-122.


• Capacitor KVARs
Find the capacitor KVARs that must be connected to the system in order to correct low power factors caused by inductive loads.


• Power cost
Estimate the financial cost of running a specific load. You enter your KWH rate, the load in KW, and the hours spent with the load connected, and the calculator will return the cost. You can select your own currency from the Preferences section.


• Preferences
The app preferences will allow you to choose to enter Values can be entered in Feet or Meters, Celsius or Fahrenheit. You can also select to use copper or aluminum cables by default, and select to use stranded or unstranded cables.


• Support
If you are not 100% satisfied with this calculator please email us at info@electriciancalculator.com so we can answer your question or comment before posting any negative reviews. We are constantly providing updates and adding new functionality. Planned updates include bend radius calculations, circuit breaker selection, SI units and more.


Note: This product is not associated with Electrician Talk, Calculated Industries, ElectriCalc, ElectriCalc Pro, nor with Electrical Calc Elite. NEC is a registered trademark of the National Fire Protection Association (NFPA). Electrical apps, electric apps.