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Electrical Wire and Cable

Figuring Volts Watts and Electrical Amperage

How to Calculate Electrical Loads and Circuits using Ohms Law: The Most Common Electrical Calculation using Ohms Law

Home Electrical Wiring Video

How To Hook Up a Generator to the House Panel
Using a Circuit Breaker Interlock Kit
for Backup Power

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Understanding and Calculating Electrical Circuit Loads
[ad#block]Electrical Question: I am trying to calculate an electric circuit for my kiln.

Background: David from Brisbane, Australia.
Additional Comments: Seems very helpful and a simple nice clean look.

Dave’s Reply:
Thanks for your electrical question David.

How to Calculate Electrical Loads and Circuits using Ohms Law

The Most Common Electrical Calculation of Ohms Law

To find out the Amperage when the voltage and watts or resistance is known simply make this electrical calculation:
Watts / Volts = Amps
3500 watts / 240 volts = 14.6 amps

More about OHMS Law and Electrical Wiring

Ohms Law Formula
Using the Ohm’s Law is a way to determine information needed to understand how to design electrical circuits.

This formula works with three main variables and depending on what is known can produce a missing factor which is needed to determine the circuit size.

The Ohm’s Law is also used when designing appliances and building electrical equipment and devices.

Electrical wire

Electrical Wire for the Home
Complete listing of electrical wire types and parts used for home projects with electrical code information serves as selection guidelines.

See Also:
Cord and Plug Safety for Electric Kilns

I was given an old, electric jewelry kiln. It draws 14 amps. No identification available. It fires up to about 1650 degrees F., but the plug would get too hot to touch. We replaced the old 2-plug Continue reading

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Dave's Guide to Home Electrical Wiring:

» You Can Avoid Costly Mistakes! «

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Wire It Right with the help of my Illustrated Wiring Book

Great for any Home Wiring Project.
  electrical wiring  

Complete Guide to Home Electrical Wiring

Perfect for Homeowners, Students,
Handyman, Handy Women, and Electricians
Wiring GFCI Outlets
Wiring Home Electric Circuits
120 Volt and 240 Volt Outlet Circuits
Wiring Light Switches
Wiring 3-Wire and 4-Wire Electric Range
Wiring 3-Wire and 4-Wire Dryer Cord and Dryer Outlet
How to Troubleshoot and Repair Electrical Wiring
Wiring Methods for Upgrading Electrical Wiring
NEC Codes for Home Electrical Wiring
....and much more.

Learn more about Home Electrical Wiring
with my Online Video Course:
Basic Home Electrical Wiring by Example

Be Careful and Be Safe - Never Work on Energized Circuits!
Consult your Local Building Department about Permits and Inspections for all Electric Wiring Projects.

Electrical Tips to Help You Wire it Right

The Safest Way to Test Electrical Devices and Identify Electric Wires!

The Non-Contact Electrical Tester
This is a testing tool that I have had in my personal electrical tool pouch for years, and is the first test tool I grab to help identify electrical wiring. It is a Non-contact tester that I use to easily Detect Voltage in Cables, Cords, Circuit Breakers, Lighting Fixtures, Switches, Outlets and Wires. Simply insert the end of the tester into an outlet, lamp socket, or hold the end of the tester against the wire you wish to test. Very handy and easy to use.

The Quickest Way to Check for Faulty Electrical Wiring!

The Plug-In Outlet Tester
This is the first tool I grab to troubleshoot a problem with outlet circuit wiring. This popular tester is also used by most inspectors to test for power and check the polarity of circuit wiring.
It detects probable improper wiring conditions in standard 110-125 VAC outlets Provides 6 probable wiring conditions that are quick and easy to read for ultimate efficiency Lights indicate if wiring is correct and indicator light chart is included Tests standard 3-wire outlets UL Listed Light indicates if wiring is incorrect Very handy and easy to use.

Strip Off Wire Insulation without Nicking and Damaging the Electric Wire!

The Wire Stripper and Wire Cutter
My absolute favorite wire stripping tool that I have had in my personal electrical tool pouch for years, and this is the tool I use to safely strip electrical wires.
This handy tool has multiple uses:
The wire gauges are shown on the side of the tool so you know which slot to use for stripping insulation.
The end of the tool can be used to grip and bend wire which is handy for attaching wire onto the screw terminals of switches and outlets..

The wire stripper will work on both solid and stranded wire. This tool is Very Handy and Easy to Use.

More articles about Electric, Kiln and Home Electrical Wiring:
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FAQs Frequently Asked Questions and Comments

2 Responses to “Figuring Volts Watts and Electrical Amperage”
  1. Julia k says:

    I want to run outdoor patio lights from one outdoor outlet. How far can I run patio lights 3000 watts, 100 feet strings? I’d like to go 300 feet, can I do that on one outlet?

  2. Dave Rongey says:

    Hi Julia,

    The distance an electrical cable may be run to supply power to a device will depend on the following:
    What is the voltage of the devices being powered, in this case, the lights themselves.
    What is the wire size of the circuit supplying the power.
    What is the cable type and that will be installed, and what are the limitations of that cable, such as temperature, amperage, and installation environment.
    What will be the method used to install the cable, such as direct burial or in conduit.

    One rule of thumb is when the length of the cable will be more than 200 feet the size of the cable is increased, however this does not apply to everything, and again, all of the above factors need to be considered as well.

    As you can see, the Device Load, and the Cable Type are Big Factors for any circuit when calculating wire size. This also applies to low voltage lighting as well.

    I hope this helps.