SpecificationsClick on a specification below to learn more about SO cord. Gauge » Temperature Rating » |
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Gauge
There are different wire gauge rating standards depending on what country you are in and even what industry you are referring to. In the U.S. and Canada, you will need to size your wires based on American Wire Gauge (AWG) ratings.
For power cables, gauge is a rating that refers to the cross-sectional area of a conductor. Since most cables are also stranded to provide increased flexibility and tensile strength, there are separate numbers to indicate the overall cross-sectional area of a conductor, the number of strands, and the cross-sectional area of each strand. Thus, if you see a cable rated at 18 AWG 16/30, that means you have an 18 AWG cable composed of 16 strands that are 30 AWG each (thinner cables have larger gauge numbers).
For portable cables like SO cord, if you just see two numbers separated by a slash, it will either refer to the conductor stranding (i.e. # of strands / gauge per strand) or the conductor gauge size / # of conductors. If the first number is smaller than the second, it most likely indicates the stranding (e.g. 16/30), but if the first number is bigger than the second, then it most likely indicates conductor gauge and number of conductors. For example, we offer 6/4 SO cord and each conductor has 133 strands. This means there are 4 conductors each rated at 6 AWG, and each conductor is made up of 133 strands to provide further flexibility. Companies may have both types of gauge listings to indicate both the conductor gauge size / # of conductors and conductor stranding.
American Wire Gauge (AWG) Reference Table
AWG | Diameter | Circular Mil | |
Inches | Millimeters | ||
4/0 | 0.46 | 11.684 | 211593.92 |
3/0 | 0.4096 | 10.4038 | 167767.34 |
2/0 | 0.3648 | 9.2659 | 133075.22 |
1/0 | 0.3249 | 8.2525 | 105556.98 |
1 | 0.2893 | 7.3482 | 83692.09 |
2 | 0.258 | 6.5532 | 66562.09 |
3 | 0.229 | 5.8166 | 52439.49 |
4 | 0.204 | 5.1816 | 41614.8 |
5 | 0.182 | 4.6228 | 33123.05 |
6 | 0.162 | 4.1154 | 26250.7 |
Ampacity
Ampacity is short for amperage capacity. It simply refers to the maximum amount of current a given conductor can handle before melting or damaging the jacketing and insulation.
Many factors will affect the ampacity ratings of portable cords. Important factors to consider when selecting your SO cord will be gauge size, cord length, insulation temperature rating, number of conductors, and ambient temperature.
Nominal Outer Diameter (Nom. OD)
This specification is used for finding a suitable type of strain relief. The nominal OD refers to the entire diameter of the cable including the outside jacket. This measurement depends on the gauge and number of conductors.
Chemical & Moisture Resistance
Depending on the application, you may want SO cord with a particular type of jacket that will be resistant to the chemicals the cable may be exposed to. TEMCo's SO Cord has a chlorinated polyethylene (CPE) jacket, a thermoplastic, that is highly resistant to chemicals and ignition (not likely to catch fire).
The OO's in SOOW refer to the oil resistant outer jacket and inner insulation. For more information on the meaning of the different letters used to describe types of flexible cable, like SO cord, see SOOW letter designations.
Strain Relief Type
Strain relief prevents flexible cables from breaking when subject to regular vibration and tension (e.g. being pulled). For example, when people accidentally trip on a power cord around the house, strain relief fittings are what prevent the conductors from getting damaged or being completely yanked loose from its (solder, screw, or crimp on) connector contacts.
The NEC requires some form of strain relief for all flexible cables. Thus, we see strain relief devices everywhere, from the flex style strain reliefs on small audio/visual cables to cable glands fitted on cables used with industrial equipment.
Connector TypesClick here for information on how to select connectors for your portable cable. The most common cause of equipment failure by far is the failing of a connection or the components that make connections. Electrical connectors are an inexpensive but vital part of any electrical equipment. Like the name suggests, connectors join together components of a circuit. Connector types come in a wide variety, but there are three basic methods of attaching conductors to the connector contacts: crimp-style, solder, or screw-on. Insulation displacement connectors (IDC), also known as fast connectors (FC), are examples of crimp connectors. Some connectors also come with their own strain relief devices. For example, RJ (Registered Jack) connectors, also known as modular or ethernet connectors, typically come with strain relief tabs. |
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Temperature Rating
SO cord is typically rated for use from -40°C to +90°C.
Acceptable for use on AC/DC
Any conductor will conduct AC or DC with no problem.
Durability and Flexibility
SO cord is stranded to increase both durability and flexibility.
Typical Applications
For a list of possible applications please see the permitted and prohibited uses of SO cord established by NEC articles 400.7 and 400.8.
SO cord can be used for portable power supply, ground testing, motor wiring, hard-service industrial tools, portable lighting, battery chargers, and applications where oil- and flame-resistant cables are needed. SO or SOOW cord is also widely used in theaters and for control booth wiring
Conductor Color CodesSee our insulation color code charts for an explanation of what the conductor colors mean. |
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Voltage Ratings and Limitations
All SO cord (SOOW cord) is rated for 600V.
Though it is not technically correct, you may see “SO cord” or “SO cable” being used as a general term to encompass SJOW and all other types of flexible or portable cables. However, actual SO cable ≠ SJ, SJO, EO, SV, etc.
Flexible cable like SJ, SJO, and SV are only rated for up to 300V applications and NOT 600V. Just be aware of whether someone is using SO cord as a general term to refer to flexible cable or is specifically referring to SO cord.
However, you can safely assume SO = SOOW cord (see the top of this page).