Product Name： Rated Voltage 3.6/6～26/35kV for XLPE insulated power cable

For XLPE (cross-linked polythene) insulated power cable, either chemical method or physical method is employed to transform the molecular structure of PE (polythene) from chain into three-dimensional network, i.e. thermoplastic PE is transformed into thermosetting XLPE. After cross-linking, the thermal and mechanical properties of PE have been greatly improved while its excellent electrical property are still retained.
The maximum permissible operating temperature of the conductor of XLPE insulated power cable is 90℃ which resistance is higher than that of PVC (polyvinyl chloride) or PE insulated power cable. The cable has the advantage of simplicity in construction, lightness in weight, convenience in application besides its excellent electrical, thermal, mechanical and anti-chemical corrosion properties. It can also be laid with no limitation of level difference along the route.

Product Standard:
The product is manufactured according to the standard of GB/T12706-2002 “Extruded solid dielectric power cables for rated voltages from 1kV(Um=1.2kV) to 35kV (Um=40.5kV)”or IEC, BS, DIN and ICEA upon request.

Application:
The product is suitable for use in power transmission and distribution lines with rated power frequency voltage 3.6/6～26/35kV.

Operating characteristics:
Rated power-frequency voltage U0/U: 3.6/6～26/35kV
Max. Permissible continuous operating temperature of conductor: 90℃.
Max. temperature of conductor during cutting-out shall not exceed 250℃.(5S maximum duration)
The circumstance temperature under installation should not below 0℃.
The bending radius of a single-core cable should not less than 20 times of the cable diameter.
The bending radius of a three-core cable should not less than 15 times of the cable diameter.

Voltage Designation:
The rated voltage of the cable for a given application shall be suitable for the operating conditions in the system in which the cable is used, and is expressed in the form of U0/U（Um）kV.
U0——The rated power-frequency voltage between conductor and earth or metallic screen, for which the cable designed;
U ——The rated power-frequency voltage between conductors, for which the cable designed;
Um——The maximum value of the “highest system voltage” for which the equipment may be used.

The values of U0 recommended for cables to be used in three-phase systems are listed below:

U kV	Um kV	U0* kV
		System categories A and B	System categories C
6	7.2	3.6	6
10	12	6	8.7
15	17.5	8.7	12
20	24	12	18
30	36	18	—
35	40.5	21	26

Note: System category  A ——This category comprises those systems in which any phase conductor that comes in contact with earth or an earth conductor, is disconnected from the system within 1 min;
System category  B ——This category comprises those system which, under fault conditions, are operated for a short time with one phase earthed. This period should not exceed 1h. For a longer period, not exceeding 8h on any occasion can be tolerated. The total duration of earth faults in any year should not exceed 125h.;
System category  C ——This category comprises all systems which do not fall into categories A and B.

Type and Description

Type	Description	Application
YJV	Copper conductor XLPE insulated and PVC sheathed power cable	For laying indoors, in tunnel or cable trench, unable to bear external mechanical forces. Single core cable in magnetic duct is not permissible.
YJLV	Aluminum conductor XLPE insulated and PVC sheathed power cable
YJY	Copper conductor XLPE insulated and PE sheathed power cable
YJLY	Aluminum conductor XLPE insulated and PE sheathed power cable
YJV22	Copper conductor XLPE insulated steel tape armoured and PVC sheathed power cable	For laying indoors, in tunnel, cable trench, or direct in ground, able to bear external mechanical forces, but unable to bear large pulling force.
YJLV22	Aluminum conductor XLPE insulated steel tape armoured and PVC sheathed power cable
YJV23	Copper conductor XLPE insulated steel tape armoured and PE sheathed power cable
YJLV23	Aluminum conductor XLPE insulated steel tape armoured and PE sheathed power cable
YJV32	Copper conductor XLPE insulated fine steel wire armoured and PVC sheathed power cable	For laying indoors, in tunnel, cable trench, well or direct in ground, able to bear external mechanical forces and certain pulling force.
YJLV32	Aluminum conductor XLPE insulated fine steel wire armoured and PVC sheathed power cable
YJV33	Copper conductor XLPE insulated fine steel wire armoured and PE sheathed power cable
YJLV33	Aluminum conductor XLPE insulated fine steel wire armoured and PE sheathed power cable

 

Production Range of Cable

Type	No. of cores	rated voltage    kV
		3.6/6	6/6 6/10	8.7/10 8.7/15	12/20	18/20 18/30	21/35	26/35
		Nom. cross-sectional area of conductor    mm²
YJV  YJLV YJY  YJLY	1	25—800	25—800	25—800	35—800	50—630	50—630	50—630
	3	25—630	25—630	25—500	35—500	50—400	50—400	50—400
YJV22  YJLV22 YJV23  YJLV23	1	25—800	25—800	25—800	35—800	50—630	50—630	50—630
	3	25—630	25—630	25—500	35—500	50—400	50—400	50—400
YJV32  YJLV32 YJV33  YJLV33	1	25—800	25—800	25—800	35—800	50—630	50—630	50—630
	3	25—630	25—630	25—400	35—400	50—240	50—185	50—150

Note: The single-core armoured cables are used for D.C system only, as for A.C system, non-magnetic armour material should be used or a magnetic isolation should be applied.

Main Technical Data of Cable
D.C. resistance of conductor and conductor maximum short circuit current

 

 

Nom.  cross- sectional  area of  conductor mm²	Max. D.C. resistance of conductor at 20℃ Ω/km		Conductor maximum short circuit current (1S) at 90℃ kA
	Copper conductor	Aluminum conductor	Copper conductor	Aluminum conductor
25	0.727	1.200	3.69	2.42
35	0.524	0.868	5.15	3.37
50	0.387	0.641	7.31	4.79
70	0.268	0.443	10.2	6.68
95	0.193	0.320	13.8	9.03
120	0.153	0.253	17.4	11.4
150	0.124	0.206	21.7	14.2
185	0.0991	0.164	26.7	17.5
240	0.0754	0.125	34.6	22.6
300	0.0601	0.100	43.1	28.2
400	0.0470	0.0778	57.4	37.6
500	0.0366	0.0605	71.7	47.0
630	0.0283	0.0469	88.8	58.0

Current carrying capacity of cable
3.6/6～12/20kV XLPE insulated power cable

conductor	Nom. cross- sectional area mm²	In the air			Under the ground
		Single-core		Three-core	Single-core		Three-core
		○ ○  ○	○○○		○ ○  ○	○○○
Copper Conductor	25	140	165	120	150	160	125
	35	170	205	140	180	190	155
	50	205	245	165	215	225	180
	70	260	305	210	265	275	220
	95	315	370	255	315	330	265
	120	360	430	290	360	375	300
	150	410	490	330	405	425	340
	185	470	560	375	455	480	380
	240	555	665	435	530	555	435
	300	640	765	495	595	630	485
	400	745	890	565	680	725	520
	500	855	1030	—	765	825	—
	630	980	1190	—	860	940	—
Aluminum Conductor	25	110	130	90	115	120	100
	35	135	155	110	135	145	120
	50	160	190	130	160	175	140
	70	200	235	165	200	215	170
	95	240	290	200	240	255	210
	120	280	335	225	270	290	235
	150	320	380	255	305	330	260
	185	365	435	295	345	370	300
	240	435	515	345	400	435	345
	300	500	595	390	455	490	390
	400	585	695	450	520	565	440
	500	680	810	—	595	650	—
	630	790	950	—	680	745	—

Note: The screen-copper-tape and steel wire (including all copper wire for magnetism separation) of single-core steel wire armoured power cable for AC system must be connected to earth well and effectively. 
The current carrying capacity is calculated by formulas of IEC. It is advised in the new edition of GB/T12706 that the current carrying capacity of steel wire armored power cable with special structure is lower than that in IEC standard, so the cross-section should be enlarged appropriately.

 

18/20～26/35kV XLPE insulated power cable

conductor	Nom. cross- sectional area mm²	In the air			Under the ground
		Single-core		Three-core	Single-core		Three-core
		○ ○  ○	○○○		○ ○  ○	○○○
Copper Conductor	50	220	245	185	215	225	200
	70	270	305	230	265	275	250
	95	330	370	280	315	330	300
	120	375	425	310	360	375	330
	150	425	485	360	400	420	380
	185	485	555	400	455	475	425
	240	560	650	470	525	555	490
	300	650	745	540	595	630	555
	400	760	870	610	680	720	625
	500	875	1000	—	775	825	—
	630	1000	1160	—	875	940	—
Aluminum Conductor	50	170	190	145	165	175	170
	70	210	235	190	200	215	190
	95	255	285	215	240	255	230
	120	290	330	240	270	290	255
	150	330	375	280	305	325	295
	185	380	430	310	345	370	330
	240	435	505	365	400	430	380
	300	510	580	430	455	490	435
	400	595	680	485	525	565	500
	500	690	790	—	600	645	—
	630	800	920	—	685	740	—

Note: The screen-copper-tape and steel wire (including all copper wire for magnetism separation) of single-core steel wire armoured power cable for AC system must be connected to earth well and effectively. The current carrying capacity is calculated by formulas of IEC. It is advised in the new edition of GB/T12706 that the current carrying capacity of steel wire armored power cable with special structure is lower than that in IEC standard, so the cross-section should be enlarged appropriately.

Installation and Operation Condition of Cable
Max. Rated temperature of the cable conductor：90℃.
Circumstance temperature in air：40℃.
Ground temperature：25℃.
Soil thermal resistivity：1.0℃.m/W.
Depth of laid：0.8m.
Single-circuit only: 
Single-core cable is installed in parallel. Adjacent space is equivalent to the diameter of the cable.

Rating factors of current carrying for different soil temperature

Soil temperature  ℃	15	20	25	30	35	40	45
Rating factor	1.07	1.04	1.0	0.96	0.92	0.87	0.83

Rating factors of current carrying for different thermal resistivity

Rating factors for soil thermal resistivity 1.0℃.m/W	1.0	1.2	1.5	2.0	2.5	3.0	3.5
Three cores	1.0	0.943	0.877	0.792	0.736	0.675	0.641
Single core	1.0	0.934	0.850	0.748	0.692	0.635	0.598

Rating factors of current carrying for different air temperature

Air temperature ℃	20	25	30	35	40	45	50
Rating factor	1.18	1.14	1.10	1.05	1.0	0.95	0.89