전선의 전류 및 저항 (IEC)

 

TABLE 1 – HV CABLE CURRENT CARRYING CAPACITIES 

Nominal conductor Cross-section (sq.mm)	Allowable Current when installed underground (A) (Armoured)	Allowable Current when installed underground (A) (Armoured)	Allowable Current when installed      in air (A) (Armoured)	Allowable Current when installed      in air (A) (Armoured)	Remarks
	1 core	3 cores	1 core	3 cores
50	-	181	-	205
70	-	220	-	253
95	-	263	-	307
120		298		352
150	-	332	-	397
185	-	374	-	453
240	-	431	-	529
150	361		473
185	406		543
240	469		641
300	526		735
400	590		845
500	679	-	990	-
630	774	-	1140	-	-

Note:   (1)    Reference soil temperature in ground           20℃

(2)    Reference ambient temperature in air            30℃

(3)    Reference thermal soil resistivity                   1.5K.m/W

(4)    Depth of laying                                            0.8 m

(5)  Reference installation :       Table B.2 for single-core cables and B.6 for three core

                                                cables of IEC 60502-2

 

 

TABLE 2 – LV CABLE CURRENT CARRYING CAPACITIES 

Nominal Conductor Cross-section (sq.mm)	Allowable Current when installed underground (A) (Armoured)		Allowable Current when installed in air  (A)  (Armoured)
	2 cores	3 cores		2 cores	3 cores
4	46	39		49	42
6	58	49		63	54
10	77	65		86	75
16	100	84		115	100
25	129	107		149	127
35	155	129		185	158
50	183	153		225	192
70	225	188		289	246
95	270	226		352	298
120	306	257		410	346
150	343	287		473	399
185	387	324		542	456
240	448	375		641	538

Note:   (1)    Reference soil temperature in ground           20℃

(2)    Reference ambient temperature in air           30℃

(3)    Reference thermal soil resistivity                   2.5K.m/W

(4)    Depth of laying                                            0.7 m

(5)  Reference installation :       Table B.52.3 , B.52.5 for underground and B.52.12

                                                For in air of IEC 60364-5-52

 

  

TABLE 3 – 33KV CABLE RESISTANCE AND REACTANCE

Nominal conductor cross-section (sq.mm) 1 CORE	Resistance (Ohm/km)	Reactance (Ohm/km)
	AC 90 °C
185	0.1272	0.1137
240	0.0973	0.1097
300	0.0781	0.1074
400	0.0618	0.1048
500	0.0492	0.1015
630	0.0394	0.0989

 

TABLE 4 – 11KV CABLE RESISTANCE AND REACTANCE

Nominal conductor cross-section (sq.mm) 1 CORE	Resistance (Ohm/km)	Reactance (Ohm/km)
	AC 90 °C
150	0.159	0.1077
185	0.1273	0.1057
240	0.0975	0.1021
300	0.0783	0.1015
400	0.0621	0.1051
500	0.0496	0.0990
630	0.0398	0.0934

 

 

TABLE 5 – 11KV CABLE RESISTANCE AND REACTANCE  

Nominal conductor cross-section (sq.mm) 3 CORE	Resistance (Ohm/km)	Reactance (Ohm/km)
	AC 90 °C
50	0.494	0.0876
70	0.343	0.0848
95	0.247	0.0820
120	0.196	0.0804
150	0.160	0.0786
185	0.1278	0.0773
240	0.0981	0.0754

 

TABLE 6 – 3.3KV CABLE RESISTANCE AND REACTANCE

Nominal conductor cross-section (sq.mm) 1 CORE	Resistance (Ohm/km)	Reactance (Ohm/km)
	AC 90 °C
150	0.159	0.1065
185	0.1274	0.1042
240	0.0975	0.1011
300	0.0783	0.1007
400	0.0622	0.0982
500	0.0496	0.0959
630	0.0399	0.0933

 

TABLE 7 – 3.3KV CABLE RESISTANCE AND REACTANCE

Nominal conductor cross-section (sq.mm) 3 CORE	Resistance (Ohm/km)	Reactance (Ohm/km)
	AC 90 °C
50	0.494	0.0842
70	0.343	0.0816
95	0.247	0.0790
120	0.196	0.0776
150	0.160	0.0760
185	0.1279	0.0748
240	0.0983	0.0734

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TABLE 8 – LV CABLE RESISTANCE AND REACTANCE  

Nominal conductor cross-section (sq.mm)	Resistance (Ohm/km)	Reactance (Ohm/km)
	AC 90 °C
4	5.88	0.092
6	3.93	0.088
10	2.33	0.083
16	1.47	0.081
25	0.927	0.079
35	0.669	0.077
50	0.494	0.076
70	0.342	0.075
95	0.247	0.073
120	0.196	0.072
150	0.160	0.073
185	0.1283	0.073
240	0.0987	0.072