A comprehensive technical explanation of voltage designation systems, resistance earthing requirements, and earth fault protection strategies that necessitate higher insulation ratings in Australian mining cable applications.
对电压标识系统、电阻接地要求和接地故障保护策略的全面技术解释，这些因素使得澳大利亚矿用电缆需要更高的绝缘等级。
Why Do Australian Mining Cables Use 1.1/1.1kV Instead of the International Standard 0.6/1kV?
A comprehensive technical explanation of voltage designation systems, resistance earthing requirements, and earth fault protection strategies that necessitate higher insulation ratings in Australian mining cable applications.
对电压标识系统、电阻接地要求和接地故障保护策略的全面技术解释，这些因素使得澳大利亚矿用电缆需要更高的绝缘等级。
Understanding Cable Voltage Designation: The Uo/U System
Before examining why Australian mining cables require a 1.1/1.1kV rating, it is essential to understand how cable voltage ratings are expressed internationally. The rated voltage of an electrical cable is normally expressed using the combination Uo/U, where both values represent root mean squared (RMS) voltages. According to the Tratos Cable Academy and international standards, Uo represents the voltage between any insulated conductor and earth (or the metallic screen/sheath), whilst U represents the voltage between any two-phase conductors of a multicore cable.
在研究为什么澳大利亚矿用电缆需要1.1/1.1kV额定电压之前，了解国际上如何表示电缆电压额定值是至关重要的。电缆的额定电压通常使用Uo/U组合表示，两个值都代表均方根（RMS）电压。根据Tratos电缆学院和国际标准，Uo代表任何绝缘导体与接地（或金属屏蔽/护套）之间的电压，而U代表多芯电缆中任意两相导体之间的电压。
For a standard international low voltage cable rated at 0.6/1kV, this indicates that the cable is designed for systems where the phase-to-earth voltage (Uo) is 0.6kV and the phase-to-phase voltage (U) is 1kV. This relationship (Uo = U/√3) corresponds to a solidly earthed three-phase system where the neutral point is directly connected to earth, maintaining a stable voltage relationship between phases and earth under all normal operating conditions.
对于额定0.6/1kV的标准国际低压电缆，这表明该电缆设计用于相对地电压（Uo）为0.6kV且相间电压（U）为1kV的系统。这种关系（Uo = U/√3）对应于固体接地三相系统，其中中性点直接接地，在所有正常运行条件下保持相位与接地之间稳定的电压关系。
Uo = U ÷ √3 = 1000V ÷ 1.732 ≈ 577V → rounded to 0.6kV
Phase-to-earth voltage is approximately 58% of phase-to-phase voltage
The Critical Difference: Earthed vs Unearthed Systems
The fundamental reason Australian mining cables utilise a 1.1/1.1kV rating lies in the earthing configuration employed in mining electrical systems. Unlike typical commercial and residential installations that use solidly earthed (TN or TT) systems, Australian mining operations predominantly employ resistance-earthed or high-impedance earthed systems, also known as IT systems in international terminology.
澳大利亚矿用电缆采用1.1/1.1kV额定电压的根本原因在于矿山电气系统所采用的接地配置。与通常使用固体接地（TN或TT）系统的商业和住宅装置不同，澳大利亚矿山作业主要采用电阻接地或高阻抗接地系统，国际术语中也称为IT系统。
- Uo (Phase-Earth): 0.6kV (600V)
- U (Phase-Phase): 1.0kV (1000V)
- Ratio Uo:U: 1:1.73 (≈ 0.58)
- Neutral: Solidly connected to earth
- Earth Fault Current: High (hundreds of amps)
- Examples: 1.9/3.3kV, 3.8/6.6kV, 6.35/11kV
- Uo (Phase-Earth): 1.1kV (1100V)
- U (Phase-Phase): 1.1kV (1100V)
- Ratio Uo:U: 1:1 (symmetrical)
- Neutral: Earthed via resistance/impedance
- Earth Fault Current: Limited (typically 5A)
- Examples: 1.1/1.1kV, 3.3/3.3kV, 6.6/6.6kV, 11/11kV
Why Resistance Earthing is Mandatory in Australian Mining
Australian mining regulations, governed by standards including AS/NZS 2081.5:2002 (Electrical equipment for coal and shale mines—Electrical protection devices) and various state mining safety regulations, mandate the use of earth fault current limiting systems. The Resources Safety & Health Queensland technical guidance confirms that earth fault current limiting impedance devices are required, with power factor specifications ensuring a significant resistive component is present in the earthing system.
澳大利亚采矿法规由AS/NZS 2081.5:2002（煤矿和油页岩矿电气设备——电气保护装置）等标准和各州矿山安全法规管理，强制要求使用接地故障电流限制系统。昆士兰资源安全与健康技术指南确认需要接地故障电流限制阻抗装置，功率因数规范确保接地系统中存在显著的电阻分量。
The primary reasons for resistance earthing in mining applications include limiting earth fault currents to typically 5 amperes or less, reducing the risk of electrical fires and explosions in potentially hazardous atmospheres (particularly critical in underground coal mining), minimising step and touch potential hazards for personnel, allowing continued operation during first earth faults whilst enabling fault location, and reducing damage to electrical equipment during fault conditions.
矿山应用中采用电阻接地的主要原因包括：将接地故障电流限制在通常5安培或以下，降低潜在危险环境（特别是地下煤矿中）电气火灾和爆炸的风险，最大限度减少人员的跨步电压和接触电位危害，允许在首次接地故障期间继续运行同时能够定位故障，以及减少故障条件下对电气设备的损坏。
⚡ Critical Safety Consideration | 关键安全考虑
As documented by the Electrical Engineering Portal, when an earth fault occurs on one phase in a resistance-earthed system, the voltage of the faulty phase with respect to earth appears across the earthing resistance. Consequently, the voltage of the two healthy phases with respect to earth rises by approximately 1.73 times (√3) the normal phase-to-earth voltage. This voltage elevation during fault conditions is the fundamental reason why cables must be rated for full phase-to-phase voltage between each conductor and earth.
正如电气工程门户网站所记录的，当电阻接地系统中某一相发生接地故障时，故障相对地电压出现在接地电阻两端。因此，两个健全相对地电压上升约1.73倍（√3）正常相对地电压。这种故障条件下的电压升高是电缆必须按每根导体与接地之间的全相间电压额定的根本原因。
Mathematical Basis for the 1.1/1.1kV Rating
In a solidly earthed 1000V three-phase system, the normal phase-to-earth voltage is approximately 577V (1000V ÷ √3). However, during a single-phase earth fault in a resistance-earthed system, the phase-to-earth voltage on the healthy phases can rise to equal the full phase-to-phase voltage. This phenomenon occurs because the resistance limits the fault current but does not provide a low-impedance path to maintain the voltage relationship.
在固体接地的1000V三相系统中，正常相对地电压约为577V（1000V ÷ √3）。然而，在电阻接地系统发生单相接地故障时，健全相的相对地电压可能上升至等于全相间电压。这种现象发生是因为电阻限制了故障电流，但没有提供低阻抗路径来维持电压关系。
Vphase-to-earth (healthy) = Vphase-to-phase × (√3/√3) = Vphase-to-phase
For 1000V system: Healthy phase-to-earth voltage rises from 577V to 1000V
对于1000V系统：健全相对地电压从577V上升到1000V
To provide adequate insulation margin under these fault conditions, Australian standards specify a 1.1/1.1kV rating (with the 1.1kV figure representing a 10% safety margin above the 1000V nominal system voltage). This symmetrical rating where Uo equals U ensures that each conductor’s insulation to earth can withstand the full phase-to-phase voltage that may appear during earth fault conditions.
为了在这些故障条件下提供足够的绝缘裕度，澳大利亚标准规定了1.1/1.1kV额定值（1.1kV数值代表高于1000V额定系统电压10%的安全裕度）。这种Uo等于U的对称额定值确保每根导体对地绝缘能够承受接地故障条件下可能出现的全相间电压。
AS/NZS Mining Cable Standards and Voltage Ratings
The Australian/New Zealand Standards governing mining cable specifications explicitly address this voltage rating requirement. AS/NZS 1802:2003 (Electric cables—Reeling and trailing—For underground coal mines) and AS/NZS 2802:2000 (Electric cables—Reeling and trailing—For mining and general use) both specify cables starting from 1.1/1.1kV rather than the international 0.6/1kV rating.
管理矿用电缆规格的澳大利亚/新西兰标准明确规定了这一电压额定要求。AS/NZS 1802:2003（电缆——卷筒和拖曳——用于地下煤矿）和AS/NZS 2802:2000（电缆——卷筒和拖曳——用于采矿和一般用途）都规定电缆从1.1/1.1kV开始，而不是国际0.6/1kV额定值。
| Standard标准 | Application应用 | Voltage Ratings电压等级 |
|---|---|---|
| AS/NZS 1802:2003 | Underground coal mining cables | 1.1/1.1kV, 3.3/3.3kV, 6.6/6.6kV, 11/11kV |
| AS/NZS 2802:2000 | Surface mining and general use | 1.1/1.1kV to 33/33kV |
| AS/NZS 1972:2006 | Underground coal (non-reeling) | 1.1/1.1kV, 3.3/3.3kV, 6.6/6.6kV, 11/11kV |
| IEC/BS (International) | General industrial use | 0.6/1kV, 1.9/3.3kV, 3.8/6.6kV, 6.35/11kV |
An essential feature mandated by AS/NZS 1802 is the requirement that cables used for alternating current supply be electrically symmetrical. This symmetry ensures balanced electrical characteristics across all phases, which is critical for proper operation of earth fault protection systems and maintaining consistent performance of the screening systems that provide personnel protection.
AS/NZS 1802规定的一个基本特征是要求用于交流电源的电缆必须电气对称。这种对称性确保所有相之间平衡的电气特性，这对于接地故障保护系统的正确运行和保持提供人员保护的屏蔽系统的一致性能至关重要。
Practical Implications for Cable Selection
The voltage rating difference has significant practical implications for engineers and procurement personnel specifying cables for Australian mining applications. A cable rated 0.6/1kV according to international standards such as IEC 60502 or BS 6724 is not suitable for use in Australian mining electrical systems, even if the nominal system voltage is 1000V or below.
电压额定值差异对为澳大利亚采矿应用指定电缆的工程师和采购人员具有重要的实际影响。根据IEC 60502或BS 6724等国际标准额定为0.6/1kV的电缆不适用于澳大利亚矿山电气系统，即使额定系统电压为1000V或以下。
📋 Key Selection Criteria | 关键选择标准
For Australian mining applications, always specify:
- Cables manufactured to AS/NZS 1802 (underground coal) or AS/NZS 2802 (surface/general mining)
- Minimum voltage rating of 1.1/1.1kV for nominal 1000V systems
- Electrically symmetrical construction
- Appropriate screen conductivity meeting the combined screen resistance requirements
- EPR (ethylene propylene rubber) insulation type R-EP-90 or XR-EP-90
对于澳大利亚采矿应用，始终指定：按AS/NZS 1802（地下煤矿）或AS/NZS 2802（露天/一般采矿）制造的电缆；额定1000V系统最低电压等级1.1/1.1kV；电气对称结构；符合组合屏蔽电阻要求的适当屏蔽导电性；EPR（乙丙橡胶）绝缘类型R-EP-90或XR-EP-90。
Higher Voltage Ratings: The Same Principle Applies
The symmetrical voltage rating principle extends throughout the Australian mining cable voltage range. Prysmian Australia and other major manufacturers confirm that mining cables are available in ratings of 1.1/1.1kV, 3.3/3.3kV, 6.6/6.6kV, 11/11kV, 22/22kV, and 33/33kV. Each of these represents an “unearthed” or “symmetrical” rating appropriate for resistance-earthed systems, in contrast to the “earthed” ratings used internationally (such as 1.9/3.3kV, 3.8/6.6kV, 6.35/11kV).
对称电压额定值原则延伸到整个澳大利亚矿用电缆电压范围。Prysmian澳大利亚和其他主要制造商确认矿用电缆有1.1/1.1kV、3.3/3.3kV、6.6/6.6kV、11/11kV、22/22kV和33/33kV等额定值。这些中的每一个都代表适合电阻接地系统的”非接地”或”对称”额定值，与国际上使用的”接地”额定值（如1.9/3.3kV、3.8/6.6kV、6.35/11kV）形成对比。
| Nominal System Voltage额定系统电压 | International Earthed Rating国际接地额定值 | Australian Mining Rating澳大利亚矿用额定值 |
|---|---|---|
| 1000V / 1kV | 0.6/1kV | 1.1/1.1kV |
| 3300V / 3.3kV | 1.9/3.3kV | 3.3/3.3kV |
| 6600V / 6.6kV | 3.8/6.6kV | 6.6/6.6kV |
| 11000V / 11kV | 6.35/11kV | 11/11kV |
| 22000V / 22kV | 12.7/22kV | 22/22kV |
| 33000V / 33kV | 19/33kV | 33/33kV |
Earth Fault Protection and Screen Requirements
The New South Wales Resources Regulator’s Electrical Protection and Earthing Guideline (EES005) specifies that earth leakage trip currents must have a maximum setting of 10% of the RMS value of earth fault limitation. For systems with 5-ampere earth fault limitation (typical in Australian mining), this means maximum earth leakage trip settings of 500mA. The cable’s screening system plays a critical role in ensuring these protection systems operate correctly.
新南威尔士州资源监管机构的电气保护和接地指南（EES005）规定，漏电跳闸电流必须有最大设定值为接地故障限制RMS值的10%。对于5安培接地故障限制的系统（澳大利亚采矿中典型），这意味着最大漏电跳闸设定为500mA。电缆的屏蔽系统在确保这些保护系统正确运行方面起着关键作用。
AS/NZS mining cables incorporate semiconductive screens over each power core, with maximum volume resistivity specifications (typically 1 Ω·m for the insulation earth screen) to ensure adequate conductivity for earth fault detection. The combined screen conductivity must meet the requirements of AS/NZS 1972 for proper integration with the mine’s earth fault protection system.
AS/NZS矿用电缆在每个电力芯上都有半导体屏蔽，具有最大体积电阻率规格（绝缘接地屏蔽通常为1 Ω·m），以确保接地故障检测的足够导电性。组合屏蔽导电性必须符合AS/NZS 1972的要求，以便与矿山的接地故障保护系统正确集成。
✅ Summary: Why 1.1/1.1kV for Australian Mining | 总结：为什么澳大利亚矿用1.1/1.1kV
Australian mining cables use 1.1/1.1kV instead of international 0.6/1kV because Australian mining electrical systems employ resistance earthing (IT systems) to limit earth fault currents for safety in hazardous environments. During an earth fault, healthy phase-to-earth voltages rise to full phase-to-phase voltage (√3 times normal). The symmetrical 1.1/1.1kV rating ensures insulation can withstand this elevated voltage with appropriate safety margin (10% above 1000V nominal). This requirement is mandated by AS/NZS 1802 and AS/NZS 2802 standards and is essential for safe operation in Australian mining conditions.
澳大利亚矿用电缆使用1.1/1.1kV而不是国际0.6/1kV，因为澳大利亚矿山电气系统采用电阻接地（IT系统）来限制接地故障电流，以确保危险环境中的安全。在接地故障期间，健全相对地电压上升到全相间电压（正常的√3倍）。对称的1.1/1.1kV额定值确保绝缘能够承受这种升高的电压并具有适当的安全裕度（高于1000V额定值10%）。这一要求由AS/NZS 1802和AS/NZS 2802标准规定，对于澳大利亚采矿条件下的安全运行至关重要。
References and Standards | 参考资料和标准
- Standards Australia / Standards New Zealand. AS/NZS 1802:2003 – Electric cables – Reeling and trailing – For underground coal mining. Intertek Inform
- Standards Australia / Standards New Zealand. AS/NZS 2802:2000 – Electric cables – Reeling and trailing – For mining and general use.
- Standards Australia. AS/NZS 2081.5:2002 – Electrical equipment for coal and shale mines – Electrical protection devices Part 5: Earth-fault current limiters.
- Tratos Group. What is Voltage Rating? – Cable Academy Technical Reference. Tratos Group
- Tratos Group. AS/NZS 1802 Mining Cables – Technical Specifications. Tratos Group
- Eland Cables. FAQ: What is Voltage Rating – Technical Guidance. Eland Cables
- Prysmian Group Australia. Mining Cables Product Range. Prysmian Australia
- Resources Safety & Health Queensland. Earth Fault Current Limiter Parameters – Safety Alert. RSHQ Queensland
- NSW Resources Regulator. EES005 – Electrical Protection and Earthing Guideline. NSW Resources
- Electrical Engineering Portal. Differences Between Earthed and Unearthed Cables. EEP
- Caledonian Cables. Reeling & Trailing Cable Electrical Characteristics – AS/NZS Mining Cables. Caledonian Cables
- SAB Cable. Nominal Voltage Uo/U of Cables and Wires – Technical Reference. SAB Cable
Contact Our Technical Team | 联系我们的技术团队
For cable selection assistance, voltage rating clarification, or technical enquiries regarding AS/NZS mining cables with correct voltage ratings for Australian applications:
如需电缆选型协助、电压额定值说明或关于适用于澳大利亚应用的正确电压额定值AS/NZS矿用电缆的技术咨询：
- WhatsApp: +86 138 5512 3218
- Technical Support 技术支持: [email protected]
- Sales 销售咨询: [email protected]
- General Enquiries 一般咨询: [email protected]
© 2025 Anhui Feichun Special Cable Co., Ltd. | 安徽飞纯特种电缆有限公司