Amps and electrical wiring, AWG - wire gauge, electrical formulas, motors and units

12 Volt 2% Wire Loss Chart

Maximum distance of various gauge two conductor copper wire

AWG - American Wire Gauge and Circular Mils

American Wire Gauge - AWG - and circular mils

AWG to square mm Wire Gauge Conversion

Convert American Wire Gauge (AWG) to square mm cross sectional area

Active, Apparent and Reactive Power

Apparent, True Applied and Reactive Power - kVA

Amps and Wire Gauge - 12V Circuit

Maximum current - amps - through a 12V circuit in combination with size (AWG) and length of wire

Asynchronous Motors - Electrical Data

Electrical motor data - nominal current, fuse, start ampere, contactor and circuit breaker of asynchronous motors

Automotive 12 Volts Electric Wiring

Current load and maximum wire length

CE Marking

The European Machine Directive

CM - Circular Mil Area

The circular mil area - CM - is a unit denoting the cross-sectional size of a wire or cable

Capacitance in Parallel and Serial Connections

Capacitors in parallel and series connections


Capacitors and capacitance - charge and unit of charge

Capacitors - Energy Stored

Energy stored and potential power generated from capacitors

Circles within Rectangles

The maximum number of circles packed in a rectangle

Circuit Wiring - Single Phase (230V) Electrical Motors

Recommended copper wire gage and transformer size for single phase - 230 Volts - electrical motors

Circuit Wiring - Three Phase (230 & 460V) Electrical Motors

Recommended copper wire gage and transformer size for Three Phase - 230 & 460V - electrical motors

Color Temperatures

Light sources and color irradiation

Colour Code for Fixed Resistors

Value and tolerance

Conductor Resistance

Resistance in plain copper wire conductor


Conductors and conductivity

Conduit Sizes

Electrical conduit trade sizes, max distance between supports

Converting Ampere between Single Phase and 3 Phase

Converting amperage between single phase (120, 240 and 480 Voltage) and three phase (240 and 480 Voltage)

Converting from NEMA to IEC Enclosure Classifications

Converting from NEMA enclosure classifications to IEC enclosure classifications

Copper Wire

Gage, circular mils, electrical resistance and weight

Coulomb's Law

The electric force acting on a point charge

Current Division

Current division circuit

Current ratings for installation

Cables for fixed installation within buildings A1, A2, B1 and B2

DIN VDE Standards

DIN VDE power installations

Electric Circuit Diagram Template

Use Google Drive to make online shareable electric circuit diagrams

Electric Shock

Physiological effect of electric shock

Electric Wire 240 Volts Single-Phase, Length and Voltage Drop

Wire length versus wire size with max. 2% voltage drop

Electric Wire Cross-Section Formulas

Calculate single and bunched wire cross-sections and diameters

Electrical Formulas

The most common used electrical formulas - Ohms Law and combinations

Electrical Heating of a Mass

Temperature change when mass is electrical heated

Electrical Motor - Full Load Current

Full load current - 460 Volts, 230 Volts and 115 Volts motors - single and 3-phase

Electrical Motor Calculator

Online electric motor calculator - calculate amps, hp and kVA

Electrical Motor Efficiency

Calculating electric motor efficiency

Electrical Motor Frame Dimensions

NEMA electrical motor frame sizes

Electrical Motor Locked Rotor Indicating Code Letters

Indicating locked rotor code letters for electrical motors

Electrical Motors - Efficiency Ratings

NEMA - electrical motors efficiency ratings

Electrical Motors - HP, Torque and RPM

Horsepower versus torque and motor velocity - rpm

Electrical Motors - Insulation Classes

Temperature and insulation classes

Electrical Motors and Heat Loss

Heat gain from electrical motors to the surroundings

Electrical Potential - e.m.f

Change in electrical potential between two points

Electrical Units

Definition of common electrical units - like Ampere, Volt, Ohm, Siemens

Electrode Potential and Galvanic Corrosion

Introduction to electro chemical series and corrosion of metals

Extension Cords

Size of extension cords - full load rating 115 V

Frequency and Speed of Electrical Motors

The velocity of 2, 4, 6 and 8 poles electrical motors at 50 Hz and 60 Hz

Full-load Currents in DC Motors

Current - Amps - in 120 and 240 Volt DC motors

IEC - NEMA Standard Torques

Comparing IEC and NEMA torque classifications of electrical motors

IEC Duty Cycles

The eight - S1 - S8 - IEC duty cycles of operating electrical motors

IP - Ingress Protection Rating

IP - Ingress Protection rating is used to specify environmental protection - electrical enclosure - of electrical equipment


Electro Magnetic Field - EMF - induced into a circuit

Inductance in Serial and Parallel Connections

Serial and parallel inductance

Inductors - Energy Stored

Energy stored in the magnetic field

Kirchhoff's Laws

Kirchhoff's current and voltage laws

Letter and Digit Code for Resistors

Indicating value of resistors by letter and digit code

Lights - Installed Power

Installed light power in some common types of buildings and rooms

Maximum Current for Wire

Maximum current for copper and aluminum wire

Motor Wiring Data - 480 Volt

Motor wiring data - NEMA Amps, Starter size, HMCP Size .. - motors ranging 1/2 - 500 HP

NEMA - National Electrical Manufacturers Association

National Electrical Manufacturers Association

NEMA A, B, C and D Design

NEMA has established four different designs - A, B, C and D - for electrical induction motors

NEMA Electrical Enclosure Types

General description of NEMA electrical enclosures types

NEMA Enclosure Standards of Electrical Motors

The NEMA enclosure standards of electrical motors

NEMA Insulation Classes

Insulation systems are rated by standard NEMA classifications to maximum allowable operating temperatures

Nema Starters

Nema size contactors

Ohm's Law

The relationships between voltage, current and resistance

Online Wire Gauge - AWG - Calculator

Calculate AWG, mil, mm, CM or square mm

Parallel Circuits

Resistors connected in parallel networks

Potential Divider

Output voltage from a potential divider

Power Factor for a Three-Phase Electrical Motor

Power Factor definition for a three-phase electrical motor

Power Wiring Color Codes

Typical power wiring color codes

Power and Horsepower in Electrical Motors

Electrical power is rated in Horsepower or Watts

Rechargeable Batteries

Properties of rechargeable batteries or accumulators

Relative Permittivity - Dielectric Constant

Some common materials and relative permittivity

Resistance Wires

Electric resistance and temperature rise in Nickel-Chromium resistance wires

Resistance and Conductance

The reciprocal of electrical Resistance is called Conductance

Resistance and Resistivity

Electrical resistance and resistivity

Resistance in Serial and Parallel Connections

Resistors in parallel and serial conections

Resistivity of Soil

Types of soil and mean value of resistivity

Resistivity, Conductivity and Temperature Coefficients for some Common Materials

Resistivity, conductivity and temperature coefficients for some common materials as silver, gold, platinum, iron and more - Including a tutorial explanation of resistivity and conductivity

Resistors - Standard Values

Preferred number series for resistors

SWG - Standard Wire Gauge

Imperial Standard Wire Gauge for sheet metal and wire

Series Circuits

Voltage and current

Service Factor

The service factor - SF - is a measure of periodically overload capacity at which a motor can operate without overload or damage

Single Phase Power Equations

Single phase electrical power equations

Slip in Electrical Induction Motors

The difference between the synchronous and asynchronous speed - also named rated speed - is

Smaller Circles in Larger Circles

A tool to estimate the number of smaller circles that fits in a larger circle - or how many pipes or wires that fits in a larger pipe

Speed of Electrical Motors with operating Loads

The speed of operating electrical motors with loads, are lower than the motors synchronous speed (no load)

Synchronous Speed of Electrical Motors

The speed at which an induction motor will operate depends on the input power frequency and the number of electrical magnetic poles in the motor

Synchronous and Full Load Speed of Induction Motors

Synchronous and approximate full load speed of amplitude current (AC) induction motors

Three Phase Electrical Motors

Full load amps - wire and conduit size

Three-Phase Power Equations

Electrical 3-phase equations

Torques in Electrical Induction Motors

There are some common torques used to describe and classify electrical motors


Alternating voltage and induced e.m.f in an ideal transformer


A transient is a high voltage spike caused by external or internal transient sources

Voltage Drop

Ohm's law and calculating voltage drop

Voltage Imbalance and Derating Factor in Polyphase Motors

The efficiency of an electrical polyphase motor decreases with increased voltage imbalance.

Wire - Convert from Square mm to Diameter mm

Convert from square mm to diameter mm

Wire Gauges - Current Ratings

Common US wire gauges - AWG gauges and their current ratings

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