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Electrical Calculations and Formulas

Voltage Drop Calculator

Summary: Basic Electrical Calculations for Voltage Drop, Wire Sizing and Power Factors help you understand the requirements for Electrical Projects and Safe Circuit Wiring.
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Electrical Calculations and Formulas

Voltage Drop Calculations
Voltage drop is an essential factor in determining the correct wire size to prevent voltage loss which will occur in long distance runs of electrical wire or cable.

Electrical Power Calculations
Electrical power calculations are required to determine the initial load requirement for any given circuit. Power Factors are identified and taken into consideration as well to maintain safety for circuit integrity and performance.

Related Discussions About Electrical Calculations and Formulas

I am wanting to run wire under ground in a conduit 160' to a 100 amp panel from a meter panel at the pole which will supply power to a carport, future plans are to enclose the carport.

Voltage Drop Calculations
Other electrical projects will require extensive consideration when it comes to voltage drop due to the length of the electric service or generator sizing especially when motors will be used, such as well pumps.

To assist you in the planning process I have selected a few resources to help you in the calculation process that I find very helpful.

Voltage Drop Calculator

Calculate the Conductor Size Based On The Project

This Calculator will determine the minimum size conductor needed based on a 3% Voltage Drop. It does not take into consideration other factors such as minimum ampacity based on the National Electric Code Table 310-16. (Allowable ampacity of conductors). Consult The Electrical Code for further details. Voltage Drop Calculation by Nick Debaggis.

Step #1 Describe the Electrical Circuit:

Conductor Type Phase Voltage
Copper Single Phase 120 Volts
Aluminum Three Phase 208 Volts
    240 Volts
    277 Volts
    480 Volts

Step #2 Describe the Application:

Distance in Feet, One-Way
Total Amperage of the Circuit

« This is the Minimum Wire Size

More Electrical Calculations and Formulas:

electrical load calculator va formula Residential Electrical Load Calculation

Generator Sizing Calculator

Ohms Law Formula

Electrical Wire and Cable Selection

Codes for Electrical Service Panels

Electrical Codes for Grounding

Electrical Codes for Underground

Electrical Projects Guidelines

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Electrical Power Calculators
Calculators to help you determine the size of generator required for your specific application.  Other calculators for unit conversions and other power related calculations.

Power Calculators

* Ask-The-Electrician takes no responsibility for any false or misleading information. The use of these calculators are the responsibility of the user only. The results produced by these calculators are not guaranteed to be correct or applicable in all situations.The user must also understand the Electrical Code may or may not be legally acceptable in their area and may be modified or superceded by the locality in which the work is installed.

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