标准编号:	GB 50070-2020
中文名称:	矿山电力设计标准
英文名称:	Standard for design of electric power in mine
中标分类:	P70    矿山、煤炭工程
行业分类:	GB    国家标准
发布机构:	中华人民共和国住房和城乡建设部 国家市场监督管理总局
发布日期:	2020-02-27
实施日期:	2020-10-1
标准状态:	现行
替代旧标准:	GB 50070-2009 矿山电力设计规范
翻译语言:	英文
文件格式:	PDF
中文字符数:	37000 字
翻译价格(元):	2590.00 元
交付时间:	付款后 1 个工作日

Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.



According to the requirements of Document JIANBIAO [2015] No.274 issued by the Ministry of Housing and Urban-Rural Development of the People's Republic of China - Notice on printing and distributing the development and revision plan on engineering construction standards and codes in 2016, the drafting group of standard has revised this standard through extensive investigation and study, careful summarization of practical experience and reference to relevant international and foreign advanced standards and on the basis of widely soliciting for opinions.



The main technical contents of this standard are: general provisions, terms, basic requirements, subterranean part of underground mine, open pit and dump of surface mine, electric traction, preparation plant and major fixed equipment.



The main technical contents revised by this standard are as follows: the relevant contents of the resistance drive system for the rotor series of wound rotor asynchronous motor in Clause 8 of the original code are deleted, and important provisions about underground distribution voltage and protective earthing are increased and modified.



The provisions printed in bold type in this standard are compulsory and must be enforced strictly.



The Ministry of Housing and Urban-Rural Development of the People’s Republic of China is in charge of the administration of this standard; China National Coal Construction Association responsible for the routine management; Beijing Huayu Engineering Co., Ltd. responsible for the explanation of specific technical contents. During the process of implementing this standard, the relevant opinions and advices, whenever necessary, can be posted or passed on to Beijing Huayu Engineering Co., Ltd. (Address: No.67, Ande Road, Xicheng District, Beijing, 100120, China).







Contents



1 General provisions 1

2 Terms 2

3 Basic requirements 4

4 Subterranean part of underground mine 9

4.1 Power supply and distribution system 9

4.2 Electric apparatus and protection 11

4.3 Cable lines 13

4.4 Electric apparatus chamber 15

4.5 Lighting 16

4.6 Protective earthing 18

5 Open pit and dump of surface mine 21

6 Electric traction 26

6.1 General requirements 26

6.2 DC traction substation 27

6.3 DC traction network 28

7 Preparation plant 35

7.1 Power supply and distribution system 35

7.2 Process flow control 36

8 Major fixed equipment 38

8.1 Hoist of underground mine 38

8.2 Main fan of underground mine 41

8.3 Main drainage pump of underground mine 41

8.4 Air compressor 42

8.5 Belt conveyor 42

8.6 Cargo ropeway 43

Explanation of wording in this standard 45

List of quoted standards 46





1 General provisions



1.0.1 This standard is formulated for the purpose of implementing national laws, regulations, principles and policies for design of electric power in mine, ensuring life safety and equipment safety, achieving reliable power supply and distribution, saving energy, being friendly to environment, using advanced technologies and being economical and reasonable.



1.0.2 This standard is applicable to electric power design for new construction, renovation and extension of various mines (except for petroleum mines).



1.0.3 The scheme and equipment level for design of electric power in mine shall be reasonably determined according to mine scale, process characteristics, load nature, electricity consumption capacity and regional power supply conditions.



1.0.4 In the design of electric power in mine, the relationship between short-term and long-term development of electric power in mine according to engineering scale, service life and development plan of the mine, with the short-term development to be given priority, and the long-term development to be reasonable considered. When conditions permit, the infrastructure shall be combined with production electricity facilities.



1.0.5 In addition to this standard, the design of electric power in mine shall also meet the requirements of the current relevant standards of the nation.



 

2 Terms



2.0.1 mining area substation

substation that distribute power to the whole or part of mining area, which usually includes several mines, surface mines, ore dressing plant and administration and production management organizations, auxiliary and affiliated enterprises in the mining area



2.0.2 surface main substation

power transformer and distribution center for enterprise located on the ground of mine or surface mine, which receives and converges the external power supply of the enterprise and has the function of distributing all or part of the load within the enterprise, also known as total step-down substation



2.0.3 underground main substation

underground transformer and distribution center which is set in the shaft station or main transportation roadway at the main mining level, receives the power supply from the mine ground, and has the function of distributing all or part of the load at this mining level (or sometimes including the adjacent mining levels), also known as underground central substation



2.0.4 working section substation

substation that distributes loads to one or more underground mining areas



2.0.5 plant of utilizing castoff or by-product in mine for generating electricity

enterprise that uses low-heat-value waste generated in mine production and processing and mining by-products such as coalbed methane as fuels to produce electricity and heat



2.0.6 mining electric apparatus for non-explosive atmospheres

electric apparatus meeting the specific safety requirements of mine and also applicable to underground normal operation area with no explosive hazards



2.0.7 underground main earthed electrode

metal-plate-type earthed electrode arranged in underground main or auxiliary dibhole



2.0.8 underground local earthed electrode

earthed electrode set in underground location equipped with centralized or separate electric apparatus, in addition to main earthed electrode



2.0.9 underground protective conductor

conductor set for underground electrical safety



 

2.0.10 underground earth device

assembly of underground earthed electrode, earth conductor and earth bus, among which the earthed device containing underground main earthed electrode is called the main earthed device, and the earthed device containing underground local earthed electrode is called local earthed device



2.0.11 underground general earth network

all earth systems which are mutually connected and have good conductivity, formed by main earthed devices and local earthed devices scattered in several underground locations which are connected with earthed conductors, at one or more underground mining levels or in underground local areas



2.0.12 underground conventional prospective touch voltage limit

maximum expected contact voltage allowed to persist for unlimited time in underground environment in order to ensure personal safety



 

3 Basic requirements



3.0.1 Mine power loads shall be divided into primary loads, secondary loads and tertiary loads, which shall meet the following requirements:



1 The following loads shall be classified as primary loads:



1) The main drainage pumps of mines with underground flooding hazards and the drainage pumps of the mining area for downhill mining;



2) The main fans of mines with the hazards of explosion or serious damage to human health;



3) The shaft hoist for frequently lifting and lowering personnel in mines;



4) The drainage pumps for open pits of surface mines with flooding hazards or drainage pumps working through roadways;



5) Other equipment that shall be regarded as primary loads according to the current relevant national standards.



2 The following shall be classified as secondary loads:



1) Single equipment or interrelated groups of equipment directly related to mineral mining, transportation, lifting, processing and outward transportation in a large mine except for the primary loads;



2) Underground fixed lighting equipment without portable lighting fixtures, or emergency lighting equipment used to ensure the continuation of normal activities in workplaces with primary loads on the ground and secondary loads in large mines;



3) Power supply equipment for mine communication and safety monitoring devices;



4) Unwatering/drainage pumps for large surface mines;



5) Signal power supply equipment for railway stations;



6) Other equipment that shall be regarded as secondary loads according to the current relevant national standards.



3 Power equipment that does not belong to the primary loads and the secondary loads shall be classified into the tertiary loads.



3.0.2 The power supply for mines should be taken from substations in the regional power system, mining area substations, power plants for coal and electricity production or power plants in mining areas (mines). When it is difficult to obtain power from the above substations or power plants, it is allowable to obtain power from substations of neighboring enterprises.



3.0.3 The power supplies and the power supply lines of mines shall meet the following requirements:



1 Mines with primary loads shall be powered by dual power supply; when one circuit of power supply is interrupted, the other circuit of power supply shall not be damaged at the same time, and the power supply capacity shall at least ensure that all the primary loads of the mines are supplied with power, and should meet the power demand of secondary loads of the mines.



2 Large and medium-sized mines should be powered by two-circuit power supply lines; when either way of the two-circuit power supply lines is interrupted, the other power supply line shall ensure that all the primary and secondary loads are supplied with power.



3 Small mines without primary loads may be powered by one-circuit power supply lines.



3.0.4 The setting of self-contained power supply in mining areas (mines) shall be determined by technical and economic comparison according to regional power development planning, overall planning of mining areas, comprehensive utilization planning, relevant national industrial policies, industry access policies, environmental and water resources protection policies, and it shall meet one of the following conditions:



1 The mine is far away from the power system, or it is difficult to obtain all the required power from the power system;



2 Sufficient low heat value waste or coal bed methane and other mining by-products for power generation are generated as fuel in the process of production and processing in the mine, where it is suitable for building a plant of utilizing castoff or by-product in mine for generating electricity;



3 The mine or its vicinity has reliable heat load and central heating conditions, which is suitable for the development of cogeneration projects;



4 There are conditions to develop other distributed generation.



 

3.0.5 The power supply voltage of mine power should be 10kV~110kV; after it is determined to be reasonable through technical and economic comparison, other levels of voltage may be used. When the economic and technical indexes of two voltages are not much different, the higher voltage should be used.



3.0.6 For a mine project where the mine power supply voltage is greater than or equal to 20kV, the primary distribution voltage of the mine should be 10kV; after it is determined to be reasonable through technical and economic comparison, the project may be supplied with power of 6kV or locally of 20kV and above voltage.



3.0.7 The number of main transformers in surface main substation of the mine shall be determined according to the following requirements:



1 For large and medium-sized mine projects, two or more sets should be used;



2 If the two power supplies of primary load of the mine need to be transformed by the main transformers, two or more sets may be used;



3 For small mine projects without primary loads, one set may be used.



3.0.8 If there are two or more main transformers in the surface main substation of the mine, when one of them stop running, the capacity of the other transformers shall be able to ensure the power supply for primary and secondary loads.



3.0.9 The neutral earthed mode for the 6kV or 10kV system in the mine shall be selected according to the requirements of uninterrupted power supply in the mine, the influence of single-phase earthed fault voltage on personal safety, the magnitude of the current of single-phase earthed capacitance, the overvoltage of single-phase earthing and the requirements for insulation level of electric apparatus, and shall meet the following requirements:



1 If a single-phase earthed fault occurs in the 6kV or 10kV system and the fault circuit needs to be kept running for a short period of time without immediate removal, the system shall be unearthed, high resistance earthed or arc suppression coil earthed, and the current flowing through the single-phase earthed fault point shall be limited within 10A;



2 If a single-phase earthed fault occurs in the 6kV or 10kV system and the fault circuit needs to be cut off quickly, the system may be low resistance earthed, and the current flowing through the single-phase earthed fault point shall be limited within 200A;



3 For the 6kV or 10kV system for supplying power to open pits and dumps of underground or surface mines, the neutral point shall not be directly earthed.



 

3.0.10 For the surface main substations in the underground mines and surface mines and other substations that distribute power to open pits and dumps in underground or surface mines, single-phase earth protection shall be set up on each 6kV or 10kV feeder wire according to the following requirements:



1 If the neutral point of the 6kV or 10kV system in a mine is unearthed, high resistance earthed or arc suppression coil earthed, selective single-phase earth protection shall be set up, and the protection shall act on signal or trip-out;



2 If the neutral point of the 6kV or 10kV system in the mine is low-resistance earthed, two-stage zero sequence current protection shall be provided; the first stage shall be zero sequence current quick break with a time limit of no more than 0.5s; the second stage shall be zero sequence overcurrent protection with a time limit that shall be the same as that of interphase overcurrent protection.



3.0.11 The electromagnetic compatibility levels of the internal coupling points of the mine power supply and distribution system should meet the requirements of the current national standard GB/T 18039.4 Electromagnetic compatibility - Environment - Compatibility levels in industrial plants for low-frequency conducted disturbances for the electromagnetic compatibility levels of Class 3 plants.



When the internal coupling points of the distribution system are used to supply power to equipment and devices sensitive to power disturbance, measures should be taken to improve the local electromagnetic environment or connect the equipment and devices with the power supply that meets the requirements of the current national standard GB/T 18039.4 Electromagnetic compatibility - Environment - Compatibility levels in industrial plants for low-frequency conducted disturbances for the electromagnetic compatibility levels of Classes 1 and 2 plants.



3.0.12 The location of the surface main substation in a mine shall meet the following requirements:



1 It shall be close to the load centers, convenient for incoming and outgoing lines;



2 It shall be economical in land utilization;



3 It should not be set up above land resources;



4 It shall be far away from pollution, environment with fire and explosive hazards, and environment with noise and vibration;



5 It should avoid unfavorable geological zones such as faults, areas with landslide hazards, low-lying areas and subsidence areas;



6 It shall be at least 200m from the mining boundary of the open pit of surface mine; at least 40m from the standard-gauge railway.



3.0.13 In addition to the relevant requirements of the nation and the power industry, the paths of fixed high-voltage overhead power lines in a mine shall be selected according to the following requirements:



1 Such lines shall not be erected in blasting operation areas and unstable waste disposal areas, and shall be kept an appropriate safe distance from them.



2 Well (mine) field boundary, fault mine pillars or other mine pillars should be used; if no mine pillars are available, the lines should seldom pass through the surface road sections of the mine and avoid passing through the initial subsidence areas.



3 If it is necessary to pass through a subsidence area due to restrictions of conditions, such lines shall seldom pass through the road section of the subsidence area, and there shall be enough safe distance between the two-circuit power lines passing through the subsidence area and other necessary safety measures shall be taken; mine power lines erected on the same poles (towers) should not pass through areas where subsidence may occur or subsidence areas which are not stable yet.

1 General provisions
2 Terms
3 Basic requirements
4 Subterranean part of underground mine
4.1 Power supply and distribution system
4.2 Electric apparatus and protection
4.3 Cable lines
4.4 Electric apparatus chamber
4.5 Lighting
4.6 Protective earthing
5 Open pit and dump of surface mine
6 Electric traction
6.1 General requirements
6.2 DC traction substation
6.3 DC traction network
7 Preparation plant
7.1 Power supply and distribution system
7.2 Process flow control
8 Major fixed equipment
8.1 Hoist of underground mine
8.2 Main fan of underground mine
8.3 Main drainage pump of underground mine
8.4 Air compressor
8.5 Belt conveyor
8.6 Cargo ropeway
Explanation of wording in this standard
List of quoted standards

1 总则
1.0.1 为在矿山电力设计中贯彻国家的法律、法规和方针政策，保障生命安全和设备安全，做到供配电可靠，节约能源、有利环保、技术先进和经济合理，制定本标准。
1.0.2 本标准适用于除石油矿山外新建、改建和扩建的各类矿山电力设计。
1.0.3 矿山电力设计方案和装备水平应按矿山规模、工艺特点、负荷性质、用电容量和地区供电条件合理确定。
1.0.4 矿山电力设计应根据矿山工程规模、服务年限和发展规划，正确处理矿山电力建设近期和远期发展的关系，以近期为主，合理地兼顾远期建设。条件允许时，应使基本建设与生产用电设施相结合。
1.0.5 矿山电力设计除应符合本标准外，尚应符合国家现行有关标准的规定。
2 术语
2.0.1 矿区变电所 mining area substation
向整个矿区或部分矿区配电的变电所，其配电范围通常包括若干矿井、露天矿、选矿厂及其矿区行政、生产管理机构、辅助和附属企业等。
2.0.2 地面主变电所 Surface main Substation
设在矿井或露天矿地面，接受、汇集本企业外部电源，具有完成企业内全部或部分负荷配电功能的企业变、配电中心。又称总降压变电所。
2.0.3 井下主变电所 underground main Substation
设置在井下主要开采水平的井底车场或运输大巷，接受引自矿井地面电源，具有完成本开采水平(或有时包括邻近开采水平)全部或局部范围负荷配电功能的井下变、配电中心。又称井下中央变电所。
2.0.4 采区变电所 working Section substation
向一个或多个井下采区范围负荷配电的变电所。
2.0.5 矿山资源综合利用电厂 plant of utilizing castoff or by-product in mine for generating electricity
利用矿山生产和加工过程中产生的低热值废物以及煤层气等采矿副产品作为燃料生产电力、热力的企业。
2.0.6 矿用一般型电气设备 mining electric apparatus for non-explosive atmospheres
满足矿山特定安全要求，适用于井下正常无爆炸危险环境场所的电气设备。
2.0.7 井下主接地极 underground main earthed electrode
设置在井下主、副水仓内的金属板式接地极。
2.0.8 井下局部接地极 underground local earthed electrode
除主接地极外在井下集中或单个装有电气设备的地点设置的接地极。
2.0.9 井下保护导体 underground protective conductor
为了井下电气安全设置的导体。
2.0.10 井下接地装置 underground earth device
井下接地极、井下接地导体和井下接地母线的总和。其中含有井下主接地极的接地装置称为主接地装置，含有井下局部接地极的接地装置称为局部接地装置。
2.0.11 井下接地网 underground general earth network
将井下多处分散的主接地装置、局部接地装置用接地导体连接，在井下一个或多个开采水平或井下局部区域范围构成相互间有良好导电性贯通的全部接地系统。
2.0.12 井下约定接触电压限值 underground conventional prospective touch voltage limit
为保证人身安全，在井下环境允许无限定时间持续存在的预期接触电压的最大值。
3 基本规定
3.0.1 矿山电力负荷应划分为一级负荷、二级负荷和三级负荷，负荷划分应符合下列规定：
1 下列情况应划分为一级负荷：
1)井下有淹没危险环境矿井的主排水泵及下山开采的采区排水泵；
2)井下有爆炸或对人体健康有严重损害的危险环境矿井的主通风机；
3)矿井经常升降人员的立井提升机；
4)有淹没危险环境露天矿采矿场的排水泵或用井巷排水的排水泵；
5)根据国家现行有关标准规定应视为一级负荷的其他设备。
2 下列情况应划分为二级负荷：
1)大型矿山中除一级负荷外与矿物开采、运输、提升、加工及外运直接有关的单台设备或互相关联的成组设备；
2)没有携带式照明灯具的井下固定照明设备，或地面一级负荷、大型矿山二级负荷工作场所用于确保正常活动继续进行的应急照明设备；
3)矿井通信和安全监控装置的电源设备；
4)大型露天矿的疏干排水泵；
5)铁路车站的信号电源设备；
6)根据国家现行有关标准规定应视为二级负荷的其他设备。
3 不属于一级负荷和二级负荷的电力设备应划分为三级负荷。
3.0.2 矿山供电电源宜取自地区电力系统的变电所、矿区变电所、煤电联营的发电厂或矿区(矿山)自备龟厂。当难以从上述变电所或电厂取得时，亦可从邻近企业变电所取得。
3.0.3 矿山供电电源和电源线路应符合下列规定：
1 有一级负荷的矿山应由双重电源供电；当一电源中断供电，另一电源不应同时受到损坏，且电源容量应至少保证矿山全部一级负荷电力需求，并宜满足矿山二级负荷电力需求。
2 大、中型矿山宜由两回电源线路供电；两回电源线路中的任一回中断供电时，另一回电源线路应保证供给全部一、二级负荷电力需求。
3 无一级负荷的小型矿山，可由一回电源线路供电。
3.0.4 矿区(矿山)自备电源的设置，应依据地区电力发展规划、矿区总体规划、综合利用规划、国家有关产业政策、行业准入政策和环境、水资源保护等政策，经技术经济比较确定，并应符合下列条件之一：
1 矿山处于远离电力系统的位置，或难以从电力系统取得全部所需电源；
2 矿山生产和加工过程中产生有足量可供发电的低热值废物或煤层气等采矿副产品作为燃料，适宜兴建矿山资源综合利用电厂；
3 矿山或矿山附近有可靠的热负荷，具备集中供热条件，适合发展热电联产工程；
4 具备发展其他分布式电源的条件。
3.0.5 矿山电源的供电电压宜采用10kV～110kV；经技术经济比较确定合理时，可采用其他等级电压。当两种电压经济技术指标相差不大时，宜采用较高等级电压。
3.0.6 矿山供电电压大于或等于20kV的矿山工程，矿山的一级配电电压宜采用10kV；经技术经济比较确定合理时，也可采用6kV或局部采用20kV及以上电压。
3.0.7 矿山地面主变电所的主变压器台数确定，应符合下列规定：
1 大、中型矿山工程宜采用2台及以上；
2 矿山一级负荷的两个电源均需经主变压器变压时，应采用2台及以上；
3 无一级负荷的小型矿山工程可采用1台。
3.0.8 矿山地面主变电所的主变压器为2台及以上时，其中1台停止运行，其余变压器容量应能保证一级负荷和二级负荷的供电。
3.0.9 矿山6kV或10kV系统中性点接地方式，应根据矿山对供电不间断的要求、单相接地故障电压对人身安全的影响、单相接地电容电流大小、单相接地过电压和对电气设备绝缘水平的要求等条件选择，并应符合下列规定：
1 当6kV或10kV系统发生单相接地故障不要求立即切除故障回路而需要维持故障回路短时期运行时，应采用不接地、高电阻接地或消弧线圈接地方式，并应将流经单相接地故障点的电流限制在10A以内；
2 当6kV或10kV系统发生单相接地故障要求迅速切除故障回路时，可采用低电阻接地方式，且应将流经单相接地故障点的电流限制在200A以内；
3 向井下或露天矿采矿场和排废场供电的6kV或10kV系统不得采用中性点直接接地方式。
3.0.10 矿井和露天矿地面主变电所和向井下或露天矿采矿场和排废场配电的其他变电所每回6kV或10kV馈出线上，应按下列规定装设单相接地保护：
1 矿山6kV或10kV系统中性点采用不接地、高电阻接地或消弧线圈接地方式时，应装设有选择性的单相接地保护，保护应动作于信号或跳闸；
2 矿山6kV或10kV系统中性点采用低电阻接地方式时，应配置二段零序电流保护；第一段应为时限不超过0.5s的零序电流速断；第二段应为零序过电流保护，时限应与相间过电流保护相同。
3.0.11 矿山供配电系统内部祸合点的电磁兼容水平宜符合现行国家标准《电磁兼容 环境 工厂低频传导骚扰的兼容水平》GB/T 18039.4对第3类工厂电磁环境的电磁兼容水平要求。
当配电系统内部祸合点供给对电源骚扰较敏感的设备、装置使用时，宜采取措施改善其局部电磁环境或使该设备、装置与符合现行国家标准《电磁兼容 环境 工厂低频传导骚扰的兼容水平》GB/T 18039.4对第1类或第2类工厂电磁环境的电磁兼容水平要求的电源连接。
3.0.12 矿山地面主变电所的位置选择，应符合下列规定：
1 应靠近负荷中心、进出线便利；
2 应节约用地；
3 不宜压占地下资源；
4 应远离污秽及火灾、爆炸危险环境和噪声、振动环境；
5 宜避开断层、滑坡、低洼、沉陷区等不良地质地带；
6 距露天矿采矿场开采边界的距离不应小于200m；与标准轨距铁路的距离不应小于40m。
3.0.13 在选择矿山固定式高压架空电力线路的路径时，除应符合国家和电力行业的有关规定外，尚应符合下列规定：
1 不应架设在爆破作业区和未稳定的排废区内，并应与其保持适当安全距离。
2 宜利用井(矿)田境界、断层矿柱或其他矿柱；当无矿柱可利用时，线路宜减少通过矿井地表的路段长度和避免通过初期沉陷区。
3 当受条件限制必须通过沉陷区时，应减少通过沉陷区的路段长度，并应使通过沉陷区两回电源线路之间有足够的安全距离和采取其他必要的安全措施；同杆(塔)架设的矿井电源线路不宜通过可能产生沉陷的地区和尚未稳定的沉陷地区。
4 矿井井下
4.1 供配电系统
4.1.1 井下变电所的设置应根据地面配电系统、井下生产规模和配电范围、排水方式和开采方法等因素确定，并应符合下列规定：
1 井下主变电所应设置在主要开采水平，作为该水平或若干个相邻开采水平的变、配电中心；井下主变电所宜设在主要开采水平井底车场且与主排水泵房相毗邻。
2 井下主变电所宜由地面主变电所直接供电。
3 负荷较大或距井下主变电所较远的采区变电所、主排水泵房变电所等，可由矿井地面主变电所或设在矿井地面的其他变电所直接供电。
4.1.2 井下配电电压和电气设备电压的选择应符合下列规定：
1 井下电力网的高压配电电压宜采用和地面高压电力网相同等级的配电电压，且应满足下列条件：
1)井下有爆炸危险环境，不得大于10kV；
2)井下无爆炸危险环境，宜采用10kV；当超过10kV时，应采取专门安全措施。
2 井下电力网的低压配电电压宜采用380/660V或1140V，小型矿山可采用220/380V。
3 综合机械化采掘工作面配电电压可采用1140V或3300V，超过3300V时应采取专门安全措施。
4 手持电气设备电压不应大于127V。
5 当安全需要时，可采用不大于36V电压。
4.1.3 井下低压配电系统接地型式应符合下列规定：
1 井下有爆炸危险环境，应采用IT系统。
2 井下无爆炸危险环境，宜采用IT系统；当采用220/380V时，也可采用TN-S系统。
3 当采用IT系统时，配电系统电源端的带电部分应不接地或经高阻抗接地，且配电系统相导体和外露可导电部分之间第一次出现阻抗可忽略的故障时，故障电流不应大于5A。
4.1.4 井下变电所的电源及供电回路设置应符合下列规定：
1 由地面引至井下主变电所和其他井下变电所的电力电缆，其总回路数不应少于两回路；当任一回路停止供电时，其余回路的供电能力应能承担井下全部负荷。
2 有一级负荷的井下主变电所、主排水泵房变电所和其他变电所，应由双重电源供电。
3 向大型矿井井下矿物开采、运输负荷配电的变电所，应采用双回路供电。
4.1.5 经由地面架空线路引入井下变电所的供电电缆，应在架空线与电缆连接处装设避雷装置。
4.1.6 由地面向井下配电的线路和其他井下线路不得装设自动重合闸装置。
4.1.7 属于下列情况之一，宜采用移动变电站配电：
1 综合机械化采掘工作面配电；
2 由采区变电所等固定式变电所配电有困难或不经济时；
3 独头大巷掘进配电、附近无适宜低压电源可利用时。
4.1.8 井下照明电压，应符合下列规定：
1 主要巷道的固定式照明电压可采用20V或127V；
2 天井以及天井至回采工作面之间应采用36V；
3 采掘工作面应采用36V，当选择矿用防爆型灯具时可采用127V；
4 行灯电压不应大于36V。
4.2 电气设备及其保护
4.2.1 井下电气设备类型选择应符合下列规定：
1 无爆炸危险环境矿井，宜采用矿用一般型电气设备；
2 有爆炸危险环境矿井，应按国家现行有关标准执行；
3 井下不应采用油浸式电气设备。
4.2.2 井下主变电所和具有低压一级负荷变电所的配电变压器不得少于2台；当其中1台停止运行时，其余变压器应能承担全部负荷。
4.2.3 井下主变电所和直接从地面受电的其他变电所的电源进线、母线分段及馈出线应装设断路器。
4.2.4 除井下主变电所和直接从地面受电的变电所外，其他变电所高压断路器的配置应符合下列规定：
1 双电源进线变电所，应设置电源进线断路器；当两回电源同时送电时，母线应分段，并应设分段断路器；
2 单电源进线的变电所，当变压器超过2台或有高压出线时，应装设进线断路器；
3 馈出线应装设断路器。
4.2.5 井下变压器一、二次侧开关的配置，应符合下列规定：
1 无爆炸危险环境矿井，变压器一次侧宜装设负荷开关；当变压器容量在315kV·A及以下时，可装设隔离开关熔断器；
2 有爆炸危险环境矿井，变压器一次侧应装设断路器；
3 变压器二次侧的总开关宜装设断路器。
4.2.6 井下高、低压线路应装设相间短路和过负荷保护。
4.2.7 当低压配电线路的短路保护电器为断路器时，被保护线路末端的最小短路电流不应低于断路器瞬时或短延时脱扣器整定电流的1.5倍。
4.2.5 井下6kV或10kV系统单相接地保护的设置应符合下列规定：
1 6kV或10kV系统中性点采用不接地、高电阻接地或消弧线圈接地方式时，井下主变电所和直接从地面受电的变电所的高压馈出线上应装有选择性的单相接地保护；接地保护应动作于跳闸或信号；向移动变电站供电的高压馈出线，应装设有选择性的单相接地保护，保护应无时限地动作于跳闸。
2 6kV或10kV系统中性点采用低电阻接地方式时，井下各级变电所高压馈线均应装设二段零序电流保护；其第一段应采用动作时限不长于0.3s的零序电流速断，直接向电动机、变压器和移动变电站供电的高压馈线应采用无时限的零序电流速断；第二段应采用零序过电流保护，时限应与相间过电流保护相同。
4.2.9 井下高、低压电气装置应设置电击防护措施，并应符合下列规定：
1 井下约定接触电压限值交流应取30V，直流应取70V。
2 有爆炸危险环境矿井，低压配电IT系统应采取自动切断电源作为电击防护措施。当发生对外露导电部分或对地的单一接地故障时，防护装置应迅速切断故障线路。
3 交流低压配电TN-S系统采取自动切断电源的电击防护措施时，供给额定电流不大于32A交流移动式设备的终端回路应装设剩余电流保护器，剩余电流保护器额定剩余动作电流不应大于30mA。
4 采用SELV和PELV特低电压作为电击防护措施时，特低电压的上限值交流不应超过25V，直流不应超过60V。
4.2.10 直接从地面接受电源的井下变电所的接地母线应与其附近的下列井下外界可导电部分做等电位联结：
1 排水、压缩空气、洒水等金属管路；
2 沿井巷装设的金属结构。
4.2.11 非直接从地面接受电源的井下变电所和移动变电站，可在局部范围内将其接地母线与本标准第4.2.10条规定的外界可导电部分就近做局部等电位联结。
4.3 电缆线路
4.3.1 电力电缆的选择应符合下列规定：
1 在立井井筒或倾角45°及以上的井巷内，固定敷设的高压电缆应采用交联聚乙烯绝缘粗钢丝铠装聚氯乙烯护套电力电缆；
2 在水平巷道或倾角小于45°的井巷内，固定敷设的高压电缆应采用交联聚乙烯绝缘钢带或细钢丝铠装聚氯乙烯护套电力电缆；
3 移动变电站的电源电缆，应采用矿用监视型屏蔽橡套电缆；
4 固定敷设的低压电缆，宜采用聚氯乙烯绝缘或交联聚乙烯绝缘电缆；
5 非固定敷设的高、低压电缆，宜采用矿用橡套软电缆；
6 移动式和手持式电气设备宜采用专用橡套电缆；
7 重要电源回路、移动式电气设备的电缆及有爆炸危险环境井下的低压电缆应采用铜芯电缆；
8 井下所有电缆应采用阻燃电缆。
4.3.2 照明电缆线路的选择应符合下列规定：
1 固定式照明线路宜采用橡套电缆或塑料电缆；
2 移动式照明线路宜采用橡套电缆。
4.3.3 电缆敷设应符合下列规定：
1 水平或倾斜巷道内的电缆悬挂的高度和位置，应使电缆在矿车、机车掉道时或其他运输车辆运行时不致受到撞击，在电缆坠落时不致落在运输机上或车辆正常运行的通道上。
2 沿钻孔敷设的电缆，应紧固在钢丝绳上，钻孔应加装金属套管。
3 电缆与水管、风管平行敷设时，电缆应在管道上方，且净距不得小于0.3m。
4 高、低压电力电缆敷设在巷道同一侧时，高压电缆应敷设在上方；高、低压电缆相互之间的净距应大于0.1m；高压电缆之间、低压电缆之间的净距，不得小于0.05m。
5 电力电缆与信息电(光)缆，不宜敷设在巷道的同一侧，当条件受限制又需同侧敷设时，电力电缆应在下方，与电话、信号电缆的净距不得小于0.1m；电力电缆与信息电(光)缆在井筒内的敷设间距，不应小于0.3m。
6 水平或倾斜巷道内的电缆悬挂点的间距，不得大于3m；立井电缆悬挂点的间距，不得大于6m。
4.3.4 除内铠装电缆外，电缆的铠装或金属外皮均应做防腐蚀处理。