Wire size is usually identified as the area of the conductor in square millimeters. The following sizes are for 60ēC insulation, copper wire, 3 current carrying conductors in a raceway. Sizes over 6 square millimeter are normally stranded so the measured diameter will be slightly larger.

These ampacities are approximate and must be modified for the environment - number of current carrying conductors in the raceway, ambient temperature, etc.

The following wire areas were translated from a Chinese Electrical Code Manual Ampacity Table.
The Chinese Electrical Code ampacities are close to the ampacities listed in the NEC.
The NEC ampacity table is below the Chinese ampacities listed here:

Single Strand (solid) conductor:

The areas in square millimeters are, apparently, standard sizes available in China.

1. 1.13 mm diameter = 1.0mm² This size is not normally used in industry – equivalent to zip-cord in U.S.
2. 1.37 mm diameter = 1.5 mm² = 15 Amp
3. 1.76 mm diameter = 2.5 mm² – 21 Amp
4. 2.24 mm diameter = 4.0 mm² – 26 Amp
5. 2.73 mm diameter = 6.0 mm² – 34 Amp
6. 3.56 mm diameter = 10.0 mm² – 46 Amp
7. 4.51 mm diameter = 16.0 mm² – 61 Amp
8. 5.64 mm diameter = 25.0 mm² – 80 Amp
9. 6.67 mm diameter = 35.0 mm² – 98 Amp
10. 7.97 mm diameter = 50.0 mm² – 121 Amp
11. 9.44 mm diameter = 70.0 mm² – 156 Amp
12. 10.99 mm diameter = 95.0 mm² – 187 Amp
13. 12.36 mm diameter = 120.0 mm² – 215 Amp
14. 13.81 mm diameter = 150.0 mm² – 262 Amp
15. 15.34 mm diameter = 185.0 mm² – 289 Amp

Wire color/conductor identification
This is the color/conductor identification I have found in Fuzhou China . . .

Single phase circuit:
Black – Ground (grounding conductor)
Blue – Neutral (grounded conductor)
Red – Ungrounded Conductor (hot – standard voltage in China is 240 for single phase utility circuits)

Three phase circuit:
Yellow – phase A
Green – phase B
Red – phase C
Blue – neutral (grounded conductor)
Black – ground (grounding conductor)

Three phase power is 360VAC, phase to phase and 240VAC phase to ground/neutral, 50Hz

The following tables compare English (NEC) wire sizes to metric wire sizes
(Areas and diameters in the following tables are for bare copper)

AWG	mm2	mm-Dia Solid	mm-Dia Stranded	60° C Amps	75° C Amps	90° C Amps
18	0.823	1.02	1.16	-	-	14
16	1.31	1.29	1.46	-	-	-
14	2.08	1.63	1.85	20	20	25
12	3.31	2.05	2.32	25	25	30
10	5.261	2.588	2.95	30	35	40
8	8.367	3.264	3.71	40	50	55

AWG	mm2	mm-Dia Stranded	60° C Amps	75° C Amps	90° C Amps
6	13.30	4.67	55	65	75
4	21.15	5.89	70	85	95
3	26.67	6.60	85	100	110
2	33.62	7.42	95	115	130
1	42.41	8.43	110	130	150
1/0	53.49	9.45	125	150	170
2/0	67.43	10.62	145	175	195
3/0	85.01	11.94	165	200	225
4/0	107.2	13.41	195	230	260
AWG	mm2	mm-Dia Stranded	60° C Amps	75° C Amps	90° C Amps
250kcmil	127	14.61	215	255	290
300kcmil	152	16.00	240	285	320
350kcmil	177	17.30	260	310	350
400kcmil	203	18.49	280	335	380
500kcmil	253	20.65	320	380	430
600kcmil	304	22.68	355	420	475
700kcmil	355	24.49	385	460	520
AWG	mm2	mm-Dia Stranded	60° C Amps	75° C Amps	90° C Amps
750kcmil	380	25.35	400	475	535
800kcmil	405	26.16	410	490	555
900kcmil	456	27.79	435	520	585
1000kcmil	507	29.26	455	545	615
1250kcmil	633	32.74	495	590	665
1500kcmil	760	35.86	520	625	705
1750kcmil	887	38.76	545	650	735
2000kcmil	1013	41.45	560	665	750

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