Siemens 8DJH 12 – blue GIS Switchgear
For Secondary Distribution Systems up to 12 kV, Gas-Insulated
Catalog HA 40.5. 2024
Application
The 8DJH 12 switchgear is a factory-assembled, type-tested, 3-pole metal-enclosed single-busbar switchgear for indoor installation. It is used in public and industrial energy systems of the secondary distribution level.
Typical Uses:
- Secondary transformer substations of power supply system operators
- Utilities transfer substations for business enterprises
- Installations of building supply technologies
- Water and sewage treatment plants
- Underground railway stations, railway stations, airports
- Charging stations for electric vehicles
- Generating plants for renewable energies (biomass, hydro power, wind turbines, solar parks)
Electrical Data and Standards
The switchgear complies with various international standards including IEC and EN standards for switchgear, switching devices, insulation, instrument transformers, insulating gas, installation, and environmental conditions.
| Parameter | 7.2 kV | 12 kV |
|---|---|---|
| Rated voltage | 7.2 kV | 12 kV |
| Rated frequency | 50 Hz | 50 Hz |
| Rated short-duration power-frequency withstand voltage | 20 kV | 28 kV |
| Rated lightning impulse withstand voltage | 60 kV | 75 kV |
| Rated peak withstand current | 52.5 kA | 52.5 kA |
| Rated short-time withstand current (3 s) | 20/21 kA | 20/21 kA |
| Rated continuous current (busbar/feeders) | 630 A | 630 A |
| Width (feeders) | 310/430/500 mm | 310/430/500 mm |
| Depth (without pressure relief duct) | 775 mm | 775 mm |
| Depth (with pressure relief duct) | 890 mm | 890 mm |
| Height (without low-voltage compartment and pressure relief duct) | 1200 / 1400 mm | 1200 / 1400 mm |
Features
Environmental Independence
The hermetically tight, welded switchgear vessels made of stainless steel and single-pole solid insulation provide resistance to aggressive ambient conditions such as saline air, humidity, dust, and condensation. They are also protected against foreign objects like dust, pollution, small animals, and humidity.
Compact Design
Utilizing natural gases (Clean Air) for insulation allows for compact dimensions, enabling efficient use of existing switchgear rooms and cost-effective new constructions, especially in urban areas.
Maintenance-Free Design
Sealed pressure systems and maintenance-free switching devices ensure maximum supply reliability, personnel safety, and reduced operating costs. The design is sealed-for-life according to IEC 62271-200.
Innovation
Digital secondary systems and combined protection and control devices allow for clear integration into process control systems and flexible adaptation to new system conditions.
Service Life
The expected service life of the gas-insulated switchgear 8DJH 12 is at least 40 years under normal service conditions, limited by the operating cycles of the installed switchgear devices.
Safety
- Safe-to-touch and hermetically sealed primary enclosure (IP65 for high-voltage parts).
- All high-voltage parts are metal-enclosed and/or provided with earthed layers.
- Panels are tested for resistance to internal faults up to 21 kA.
- Capacitive voltage detecting system for safe isolation.
- Logical mechanical interlocks prevent maloperation.
- Feeder earthing via make-proof earthing switches.
Security of Operation
- Hermetically sealed primary enclosure, independent of environmental effects.
- Welded switchgear vessels, sealed for life.
- Maintenance-free in indoor environments.
- Operating mechanisms accessible outside the primary enclosure.
- Metal-coated, plug-in inductive voltage transformers.
- Ring-core current transformers mounted outside the switchgear vessel.
- Complete switchgear interlocking system.
- Mechanical position indicators.
- Minimum fire load.
- Optional resistance against earthquakes.
Reliability
- Type and routine-tested.
- Manufactured using numerically controlled machines.
- Quality assurance in accordance with DIN EN ISO 9001.
- Over 1,500,000 Siemens switchgear panels in operation worldwide.
Technology
The 8DJH 12 switchgear is 3-pole metal-enclosed and features high-voltage compartments with metal partitions. The switchgear vessel is hermetically tight and welded stainless steel, with welded-in bushings. The front covers and doors are powder-coated light gray (RAL 7035).
Modular Design
Individual panels and panel blocks can be lined up and optionally extended without gas work on site. Low-voltage compartments are available in various heights, with installation and removal possible on site.
Instrument Transformers
Ring-core current transformers are not subjected to dielectric stress. Metal-coated, plug-in voltage transformers are used. Cast-resin insulated block-type current and voltage transformers are available for air-insulated metering panels.
Sensors
Current sensors utilize inductive current transformers with precision shunts, and voltage sensors use resistor dividers. These are compatible with secondary devices like SICAM FCM and 7SJ81.
Vacuum Circuit-Breaker
The vacuum circuit-breaker is maintenance-free under normal ambient conditions according to IEC 62271-1, offering 2000 operating cycles and vacuum-tightness for life.
Secondary Systems
The switchgear accommodates customary protection, measuring, and control equipment. Numerical multifunction protection relays with integrated functions are available as an option and can be integrated into process control systems.
Digitalization, Condition Monitoring
Siemens Xcelerator is an open digital business platform designed to accelerate digital transformation. The 8DJH 12 switchgear supports various monitoring functionalities for enhanced grid stability, cyber and asset security, and reduced expenditures.
Available Monitoring Functionalities:
- Condition Monitoring: Improves resilience, reliability, and availability, enabling early indication of irregularities.
- Temperature Monitoring of Cable Connections: Ensures thermal service conditions are not exceeded.
- Temperature and Humidity Monitoring (Dew-Point Monitoring): Prevents corrosion caused by condensation.
- Partial Discharge Monitoring: Detects potential insulation damage.
- Digital Gas Density Monitoring: Ensures correct gas density for optimal operation.
- Circuit-Breaker Monitoring: Evaluates the health status of circuit-breakers based on mechanical and electrical parameters.
- Load Flow Monitoring: Captures data to identify grid hotspots and improve planning security.
Digitalization solutions are offered from a single source, integrating control, substation, and cloud levels with components like SICAM, SIPROTEC, and NXpower Monitor.
Sustainability
Siemens is committed to sustainability, focusing on decarbonization, resource efficiency, and environmental protection. The blue GIS portfolio emphasizes Clean Air as an insulating medium and eco-efficient design to reduce the CO2 footprint throughout the product lifecycle.
Key Sustainability Features:
- F-gas-free insulation: Utilizes Clean Air (GWP < 1), minimizing environmental impact.
- Space efficiency: Compact solutions that save space and reduce environmental impact.
- Material efficiency: Designed for a low CO2 footprint, with examples like SIBushing reducing raw material usage.
- Energy efficiency: Optimized main current path reduces power loss.
- Long service life: Expected service life of 40 years minimizes re-investment cycles.
- Maintenance-free design: Reduces CO2 footprint by avoiding site visits.
- Sustainable services: Predictive maintenance, condition monitoring, and paperless documentation contribute to reduced CO2 footprint.
The complete lifecycle is considered, with robust Eco Design principles applied from the design phase to minimize environmental impact and prioritize resource efficiency and circular economy. The end-of-life phase of the 8DJH 12 – RRL block blue GIS is modeled for recyclability and energy recovery.
Siemens adheres to ISO 14021 standards for Environmental Product Declarations (EPDs) and conducts Life Cycle Assessment (LCA) studies.
Technical Data
Switchgear
| Parameter | 7.2 kV | 12 kV |
|---|---|---|
| Rated voltage | 7.2 kV | 12 kV |
| Rated short-duration power-frequency withstand voltage (Ud) | 20 kV | 28 kV |
| Rated lightning impulse withstand voltage (Up) | 60 kV | 75 kV |
| Rated frequency (f) | 50 Hz | 50 Hz |
| Rated continuous current (In) | 630 A | 630 A |
| 50 Hz Rated short-time withstand current (Ik) | 21 kA | 21 kA |
| Rated peak withstand current (Ip) | 52.5 kA | 52.5 kA |
| Filling level (pressure values at 20 °C) | 1.6 kPa (absolute) | 1.6 kPa (absolute) |
| Minimum functional level (pme) | 1.5 kPa (absolute) | 1.5 kPa (absolute) |
| Ambient air temperature (Operation) | -25 to +55 °C (standard) | -25 to +55 °C (standard) |
| Storage/transport | -25 to +55 °C (standard) | -25 to +55 °C (standard) |
| Degree of protection | IP65 (gas-filled switchgear vessel), IP2X/IP3X (switchgear enclosure), IP3X/IP4X (low-voltage compartment) | IP65 (gas-filled switchgear vessel), IP2X/IP3X (switchgear enclosure), IP3X/IP4X (low-voltage compartment) |
| Partition class | PM | PM |
| Loss of service continuity category | LSC2 | LSC2 |
| Accessibility to compartments (enclosure) | Non-accessible | Non-accessible |
| Internal arc classification (option) | IAC A | IAC A |
Switching Devices
| Device Type | Parameter | 7.2 kV | 12 kV |
|---|---|---|---|
| Three-position switch-disconnector | Rated mainly active load breaking current (Iload) | 630 A | 630 A |
| Rated short-circuit making current (Ima) | up to 52.5 kA | up to 52.5 kA | |
| Electrical endurance (Iload) | Class E3 | Class E3 | |
| Number of electrical operating cycles (Iload) | 100 | 100 | |
| Number of short-circuit making operations (Ima) | 5 | 5 | |
| Capacitive switching | Class C2 | Class C2 | |
| Mechanical endurance | Class M1 | Class M1 | |
| Disconnector function | Mechanical endurance | Class M0 | Class M0 |
| Number of mechanical operating cycles | 1000 | 1000 | |
| Make-proof earthing switch function | Rated short-circuit making current (Ima) | up to 52.5 kA | up to 52.5 kA |
| Electrical endurance | Class E2 | Class E2 | |
| Number of short-circuit making operations (Ima) | 5 | 5 | |
| Mechanical endurance | Class M0 | Class M0 | |
| Number of mechanical operating cycles | 1000 | 1000 | |
| Vacuum circuit-breaker with three-position disconnector | Rated operating sequence | O-3 min - CO - 3 min – CO | O-3 min - CO - 3 min – CO |
| Rated short-circuit breaking current (Isc) | up to 21 kA | up to 21 kA | |
| Electrical endurance (Isc) | Class E2 | Class E2 | |
| Number of short-circuit breaking operations (Isc) | up to 20 | up to 20 | |
| Capacitive switching | Class C2 | Class C2 | |
| Switching of cable systems | Class S1 | Class S1 | |
| Mechanical endurance | Class M1 | Class M1 | |
| Number of mechanical operating cycles | 2000 | 2000 | |
| Disconnector function | Mechanical endurance | Class M0 | Class M0 |
| Number of mechanical operating cycles | 1000 | 1000 | |
| Make-proof earthing switch function | Mechanical endurance | Class M0 | Class M0 |
| Number of mechanical operating cycles | 1000 | 1000 |
Product Range
Individual Panels
- Ring-main feeder (R): Features a three-position disconnector, vacuum circuit-breaker, or three-position switch-disconnector. Includes options for capacitive voltage detecting systems, surge arresters, cable-type current transformers, voltage transformers, voltage sensors, current sensors, cable connections, and SIBushing. Dimensions typically 775 mm width and 1400 mm height.
- Circuit-breaker feeder (L): Similar to the ring-main feeder, with options for various components. Dimensions typically 775 mm width and 1400 mm height, with a feeder width of 430/500 mm.
- Cable feeder (K): Designed for cable connections, with similar component options. Dimensions typically 775 mm width and 1400 mm height, with a feeder width of 310 mm.
Air-insulated Billing Metering Panels Type M (840 mm wide)
These panels are available with cable connections on the left, right, or both sides, and with busbar connections on both sides. They incorporate current transformers (cast-resin insulated), voltage transformers (cast-resin insulated), and capacitive voltage detecting systems.
Panel Blocks
- RL (1 ring-main feeder, 1 circuit-breaker feeder): Dimensions approximately 775 mm width and 1400 mm height.
- RRL (2 ring-main feeders, 1 circuit-breaker feeder): Dimensions approximately 775 mm width and 1400 mm height, with a total width of 1050 mm.
- KL (1 cable feeder, 1 circuit-breaker feeder): Dimensions approximately 775 mm width and 1400 mm height.
- KRL (1 cable feeder, 1 ring-main feeder, 1 circuit-breaker feeder): Dimensions approximately 775 mm width and 1400 mm height, with a total width of 1050 mm.
Design
Overview
The 8DJH 12 switchgear features a modular design with various components:
- 1 Low-voltage compartment: Optional, available in heights of 200, 400, 600, or 900 mm for secondary equipment.
- 2 Busbar extension, modularity: Plug-in units for flexible configuration without gas work.
- 3 Indicators: Voltage detecting systems, short-circuit/earth-fault indicators, and transformer monitors.
- 4 Three-position switch-disconnector: Meets IEC 62271-103 and IEC 62271-102 standards, with CLOSED, OPEN, and EARTHED positions.
- 5 Vacuum circuit-breaker: Meets IEC/EN 62271-100 and IEC/EN 62271-102 standards, maintenance-free.
- 6 Enclosure: Hermetically tight, welded stainless steel switchgear vessel.
- 7 SIBushing: Outside-cone bushing type C with integrated measurement of current, voltage, and temperature.
- 8 Cable compartment: Bushings according to DIN EN 50181 with outside cone and bolted connection M16 (interface type C). Options for cable elbow plugs, T-plugs, and various cable types.
- 9 Dimension options: Switchgear heights of 1200 mm and 1400 mm.
- 10 Pressure relief: Options for pressure relief downwards, to the rear, or upwards, with or without ducts.
Panel Design (Examples)
Detailed sectional views are provided for Ring-main feeder (Type R), Cable feeder (Type K), Circuit-breaker feeder (Type L), and Billing metering panel (Type M), illustrating the internal arrangement of components.
Outdoor Enclosure
Outdoor enclosures are available with pressure relief downwards, to the rear, or upwards. Dimensions are provided for various configurations, including switchgear height, low-voltage compartment, and cable connection depths.
Components
Busbar Extension, Modularity
Busbar extensions are available as an option for individual panels and panel blocks, facilitating flexible switchgear configurations without the need for gas work during installation or extension. Interconnecting panels utilize plug-in units with contact couplings and screened silicone couplings.
Cable Connection with Interface Type C
Access to the cable compartment is only possible after disconnection and earthing of the feeder. Bushings conform to DIN EN 50181 with outside cone and bolted connection M16. Various cable plug types, including screened and insulated options, are supported. Surge arresters and surge limiters can be connected directly at the cable T-plug.
Current Transformers, Voltage Transformers
A range of current transformers (cable-type, three-phase, block-type) and voltage transformers (plug-in, cast-resin insulated) are available, complying with IEC/EN 61869 standards. They are designed for various installation locations within the switchgear.
Current Sensors and Voltage Sensors
Zelisko current sensors (ring-core) provide a voltage signal through a precision shunt, suitable for measuring, protection, and earth-fault detection. Voltage sensors are resistor dividers providing an output signal of 3.25 V/√3. Both are compatible with secondary devices like SICAM FCM and SIPROTEC Compact.
SIBushing
The SIBushing is an alternative to conventional cable connection bushings, providing current, voltage, and temperature measurement values in low-signal technology. It is compatible with voltage detecting and indicating systems according to IEC 62271-213.
Low-Voltage Compartment, Low-Voltage Niche
Optional low-voltage compartments can be equipped with protection, control, measuring, and metering devices. Low-voltage niches are integrated into the panel front of billing metering panels type M for accommodating options like voltage transformer m.c.b.s or fuse boxes.
Dimensions
Room Planning
The document provides guidance on switchgear installation, including wall-standing and free-standing arrangements. It details control aisle requirements (minimum 800 mm in front of the switchgear) and wall distances (minimum 200 mm for panel replacement). Pressure relief options affect switchgear depth and room requirements.
Switchgear Heights
Switchgear heights of 1200 mm and 1400 mm are available, with corresponding overall dimensions provided for different configurations.
Pressure Relief
Type-tested pressure relief systems are available for downwards, rear, or upwards relief. Specific requirements for internal arc classification (IAC A FL / FLR) and minimum room heights are detailed for each version, along with illustrations of switchgear installation with different pressure relief configurations.
