Wire

Types of Wire and Cable

There are two basic types of wire: STRANDED and SOLID CORE. Stranded wire is more flexible than solid core wire, and solid core wire is less expensive, carries more current, and handles harsher environments. Wire is available individually, in jacketed bundles, and in shielded jacketed bundles. It is also available in coaxial arrangements where a central wire is surrounded by an insulator and then a conductive foil or braid.

Jacket refers to an insulating cover around a wire or wires, and shield refers to a conductive sheath that surrounds but is insulated from a wire or wires. The purpose of a shield is to act as a Faraday Cage and block electromagnetic interference, to prevent the wire from emitting it, and to block it from reaching the wire.

Fiber-optic cable is another type of cable that conducts light instead of electric signals. It is used for transferring high rates of data as it can transmit very high frequency signals. Fiber-optic cables also provide electrical isolation, which is important for long-distance connections that can have large earth ground voltage differences. And, they do not emit electromagnetic interference nor are they susceptible to it.

Wire Size

The size of wire is specified by its gauge (American Wire Gauge or AWG) or by its diameter in mm. Resistance of wire is inversely proportional to the cross-sectional area of the wire, so wire with a larger diameter has less resistance per unit distance.

AWG	Diameter (mm)	Ω/1000 ft.	Ω/km	Max current for chassis wiring (A)	Max current for power transmission (A)	Max freq for 100% skin depth
0	8.25246	0.0983	0.322424	245	150	250 Hz
1	7.34822	0.1239	0.406392	211	119	325 Hz
2	6.54304	0.1563	0.512664	181	94	410 Hz
3	5.82676	0.197	0.64616	158	75	500 Hz
4	5.18922	0.2485	0.81508	135	60	650 Hz
5	4.62026	0.3133	1.027624	118	47	810 Hz
6	4.1148	0.3951	1.295928	101	37	1100 Hz
7	3.66522	0.4982	1.634096	89	30	1300 Hz
8	3.2639	0.6282	2.060496	73	24	1650 Hz
9	2.90576	0.7921	2.598088	64	19	2050 Hz
10	2.58826	0.9989	3.276392	55	15	2600 Hz
11	2.30378	1.26	4.1328	47	12	3200 Hz
12	2.05232	1.588	5.20864	41	9.3	4150 Hz
13	1.8288	2.003	6.56984	35	7.4	5300 Hz
14	1.62814	2.525	8.282	32	5.9	6700 Hz
15	1.45034	3.184	10.44352	28	4.7	8250 Hz
16	1.29032	4.016	13.17248	22	3.7	11 k Hz
17	1.15062	5.064	16.60992	19	2.9	13 k Hz
18	1.02362	6.385	20.9428	16	2.3	17 kHz
19	0.91186	8.051	26.40728	14	1.8	21 kHz
20	0.8128	10.15	33.292	11	1.5	27 kHz
21	0.7239	12.8	41.984	9	1.2	33 kHz
22	0.64516	16.14	52.9392	7	0.92	42 kHz
23	0.57404	20.36	66.7808	4.7	0.729	53 kHz
24	0.51054	25.67	84.1976	3.5	0.577	68 kHz
25	0.45466	32.37	106.1736	2.7	0.457	85 kHz
26	0.40386	40.81	133.8568	2.2	0.361	107 kHz
27	0.36068	51.47	168.8216	1.7	0.288	130 kHz
28	0.32004	64.9	212.872	1.4	0.226	170 kHz
29	0.28702	81.83	268.4024	1.2	0.182	210 kHz
30	0.254	103.2	338.496	0.86	0.142	270 kHz

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