Summary: The amperage capacity of electrical wire is determined by a few factors. The insulation materials used to protect the actual wire conductor are an important factor when selecting an electrical wire or cable. The following table demonstrates Standard Over Current Devices with 75 Degree Rated Terminals.
It is essential to understand that there are allowable ampacities of insulated wire conductors.
The insulation materials used to protect the actual wire conductor are designed for specific applications.
Some types of wire insulation protect the wire against overheating and external elements such as direct sunlight exposure, moisture as well as some corrosive substances, to mention just a few.
Not all wire insulation types are designed the same, therefore they have specific amperage capacities.
The wire or conductor size and type is determined by the by the specific application and the load requirement. Other considerations that will affect the wire size may be the total length of the run of wire to be installed and if the wire will be installed into conduit or in an open air environment.
This table shows the Amperage Rating for Home Electrical Wire Sizes
Although this is the most common table used to determine wire size, this is just one example.
Standard Over Current Devices with 75 Degree Rated Terminals
Circuit
Size
Copper Cable
Type NM, NM-B
Copper Cable
Type SE, USE
Aluminum Cable
Type SE, USE
15
#14
-
-
20
#12
#12
#12
25
#10
#12
#10
30
#10
#10
#10
35
#8
#8
#8
40
#8
#8
#8
45
#6
#8
#6
50
#6
#8
#6
55
#6
#6
#4
60
#4
#6
#4
65
#4
#6
#4
70
#4
#4
#3
75
#3
#4
#3
80
#3
#3
#2
85
#3
#3
#2
90
#2
#3
#2
100
#1
#3
#1
115
1/0
#2
1/0
120
1/0
#1
1/0
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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.
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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
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Light indicates if wiring is incorrect
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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.
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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.
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electrical wire capacity - 1533
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Electrical Wiring Codes
Electrical Project Skill Level:
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Electrical Tools Required:
Basic Electricians Pouch of Hand Tools, Battery Tools, Electric Power Tools, Electrical Meters and Voltage Testers.
Estimated Time:
Depends on personal level of working capabilities and electrical experience, electrical certification or contractors license, ability to work with tools, install electrical circuit wiring, and the available access to the project area. Electrical Safety:
Identify the electric panel circuits found in the project area, turn them OFF and Tag them with a Note before working with the electrical wiring.
Electrical Wiring Parts and Materials:
Electrical parts and materials for all electrical projects should be approved for the specific project and compliant with local and national electrical codes.
Electrical Codes and Inspections:
Installing additional electrical circuits or wiring should be done according to local and national electrical codes with a permit and be inspected.
This is a testing tool that 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.
This is great to troubleshoot a problem with outlet circuit wiring, 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.
A wire stripping tool used 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.
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