RDS-PP to RDS-PS: Understanding the Evolution in Power System Classification

A detailed comparison of RDS-PP and RDS-PS reference designation systems for power generation and electrical systems, exploring how RDS-PS improves upon RDS-PP with enhanced flexibility and broader applications.

The Evolution from RDS-PP to RDS-PS in Power Systems

Reference Designation Systems (RDS) are the backbone of power plant documentation and electrical system asset management. While RDS-PP (Power Plants) established the foundation for power generation facility classification, RDS-PS (Power Systems) represents a significant evolution based on enhanced IEC 81346 standards, offering improved flexibility for modern electrical systems and broader power infrastructure applications.

Understanding the improvements RDS-PS brings over RDS-PP is crucial for engineering teams in power generation, transmission, distribution, and industrial electrical systems.

Historical Context: Why Two Power Standards?

RDS-PP: The Power Plant Foundation

RDS-PP, based on IEC 81346-1 and IEC 81346-2, was specifically developed for power generation facilities. Its structure was optimized for:

  • Coal-fired power plants
  • Gas turbine and combined cycle plants
  • Nuclear power stations
  • Hydroelectric facilities
  • Traditional utility-scale generation

RDS-PS: The Power Systems Evolution

RDS-PS emerged as an evolution of IEC 81346 standards, designed to address the limitations of RDS-PP and provide enhanced capabilities for:

  • Modern renewable energy systems (wind, solar, storage)
  • Electrical transmission and distribution networks
  • Industrial power systems and substations
  • Smart grid and digital power infrastructure
  • Hybrid and distributed generation facilities

Key Improvements in RDS-PS Over RDS-PP

1. Enhanced System Scope and Flexibility

RDS-PP Limitation:

Power Plant-Specific Structure:
Level 1 - Plant Systems (Steam, Water, Electrical)
Level 2 - Equipment Groups (Turbine, Generator, Boiler)
Level 3 - Individual Equipment
Level 4 - Components

RDS-PS Improvement:

Flexible Power System Structure:
Function Aspect (=): Functional area/system
Location Aspect (+): Physical location/area  
Product Aspect (-): Equipment/device type

Example: =1GAA+10AA-G001
(Generator system, Unit 1, Generator 001)

RDS-PS provides much greater flexibility for modern power systems that don't fit the traditional centralized generation model.

2. Broader Power Industry Application

RDS-PP Limitation:

  • Centralized power plant focus
  • Traditional generation emphasis
  • Limited renewable energy support
  • Minimal grid integration capability

RDS-PS Improvement:

  • Comprehensive electrical power system coverage
  • Enhanced renewable energy integration
  • Smart grid and distributed energy resources
  • Transmission and distribution system support

Real-World Comparison:

RDS-PP designation for a generator:

1GAA G001
(Unit 1, Electrical, Generator 001 - traditional format)

RDS-PS designation for the same generator:

=1GAA+10AA-G001
(Function: Unit 1 Generator system, Location: Unit 10 Area A, Product: Generator 001)

3. Improved Multi-Aspect Designation

One of RDS-PS's most significant improvements is its clear separation of different aspects of power system objects.

RDS-PP: Mixed functional and locational designation RDS-PS: Three distinct, separated aspects:

Function aspect (=)  - What electrical function does it serve?
Location aspect (+)  - Where is it physically located?
Product aspect (-)   - What type of equipment is it?

Power Plant Example:

=1HAB+20AB-P001
│   │    └── Product: Pump 001
│   └────── Location: Building 20, Area B  
└────────── Function: Unit 1 Feedwater system

This tri-aspect approach eliminates confusion between electrical function, physical location, and equipment type in complex power facilities.

4. Enhanced Renewable Energy Support

RDS-PP Challenges:

  • Designed for traditional thermal plants
  • Limited support for variable generation
  • Difficulty with distributed resources
  • Poor wind/solar array handling

RDS-PS Advantages:

  • Native support for renewable technologies
  • Excellent wind farm and solar array classification
  • Battery energy storage system integration
  • Microgeneration and distributed energy resources

Renewable Energy Examples:

Wind Farm in RDS-PS:

=1WGA+A01-WTG001  (Wind Turbine Generator 001, Array A01)
=1WGA+A01-T001    (Transformer 001, Array A01)  
=1WGA+SUB-SW001   (Switchgear 001, Substation)

Solar Plant in RDS-PS:

=1PVA+F01-INV001  (Inverter 001, Field 01)
=1PVA+F01-STR001  (String 001, Field 01)
=1PVA+SUB-TR001   (Transformer 001, Substation)

5. Superior Digital Integration

RDS-PP Challenges:

  • Developed before smart grid era
  • Limited IoT sensor integration
  • Basic SCADA system support
  • Manual data collection emphasis

RDS-PS Advantages:

  • Designed for digital power systems
  • Seamless IoT and smart meter integration
  • Advanced SCADA and DCS connectivity
  • Real-time monitoring and control ready

Digital Implementation Example:

RDS-PP in control systems:

-- Traditional hierarchical queries
SELECT * FROM equipment 
WHERE plant_unit = '1' 
AND system_code = 'GAA'
AND equipment_type = 'G'

RDS-PS in modern power management:

-- Multi-aspect queries for smart systems
SELECT * FROM power_equipment 
WHERE function_aspect = '1GAA'
AND location_aspect = '10AA'
AND product_type = 'G'
AND status = 'ONLINE'

6. Enhanced Grid Integration and Connectivity

RDS-PP Limitation:

  • Plant-boundary focus
  • Limited grid interface consideration
  • Minimal transmission integration

RDS-PS Improvement:

  • Comprehensive grid connectivity
  • Transmission and distribution integration
  • Substation and switching facility support
  • Smart grid communication protocols

Grid Integration Example:

Power Plant Interconnection:

=1GAA+GEN-G001    (Generator in generation area)
=1TRA+YRD-TR001   (Main power transformer)
=1SWG+YRD-CB001   (Circuit breaker to grid)
=GRID+INT-PT001   (Grid interconnection point)

7. Modern Maintenance and Asset Management

RDS-PP Challenges:

  • Traditional time-based maintenance
  • Limited condition monitoring
  • Manual inspection emphasis
  • Equipment-centric approach

RDS-PS Advantages:

  • Condition-based maintenance ready
  • Predictive analytics integration
  • System-wide health monitoring
  • Performance optimization focus

Maintenance Planning Example:

Traditional RDS-PP maintenance:

1GAA G001 - Generator annual overhaul
1GAA T001 - Turbine 6-month inspection  
1HAB P001 - Pump quarterly service

Modern RDS-PS maintenance:

=1GAA+10AA-G001   - Generator (CBM enabled)
=1GAA+10AA-T001   - Turbine (vibration monitored)
=1HAB+20AB-P001   - Pump (thermal imaging)
All linked to system performance optimization

Power System Applications

Traditional Power Plants

Coal and Gas Plants:

=1STM+BLR-001     (Steam system, Boiler 001)
=1STM+TUR-001     (Steam system, Turbine 001)
=1GAA+GEN-001     (Generator system, Generator 001)
=1ELE+TRA-001     (Electrical system, Transformer 001)

Nuclear Plants:

=1RCT+RPV-001     (Reactor system, Reactor Pressure Vessel)
=1STM+SG-001      (Steam system, Steam Generator 001)
=1CON+CRD-001     (Control system, Control Rod Drive 001)

Renewable Energy Systems

Wind Farms:

=WF01+A01-WTG001  (Wind Farm 01, Array A01, Wind Turbine 001)
=WF01+A01-MET001  (Wind Farm 01, Array A01, Met Tower 001)
=WF01+SUB-TR001   (Wind Farm 01, Substation, Transformer 001)

Solar Power Plants:

=PV01+F01-INV001  (PV Plant 01, Field 01, Inverter 001)
=PV01+F01-STR001  (PV Plant 01, Field 01, String 001)
=PV01+TRK-001     (PV Plant 01, Tracker system 001)

Battery Energy Storage:

=BES1+R01-BAT001  (Battery system 1, Rack 01, Battery 001)
=BES1+PWR-PCS001  (Battery system 1, Power conversion, PCS 001)
=BES1+CTL-BMS001  (Battery system 1, Control, BMS 001)

Migration Considerations

When to Stay with RDS-PP

Keep RDS-PP for:

  • Existing traditional power plants with established systems
  • Simple generation-only facilities
  • Regulatory requirements specifying RDS-PP
  • Legacy SCADA systems not easily upgraded

When to Adopt RDS-PS

Move to RDS-PS for:

  • New renewable energy projects
  • Smart grid implementations
  • Multi-technology power facilities
  • Modern digital power management systems
  • Grid-scale energy storage projects

Migration Strategy for Power Facilities

Phase 1: Power System Assessment

1. Document current RDS-PP implementation
2. Identify grid integration requirements  
3. Map renewable energy additions
4. Assess digital system needs

Phase 2: Standards Mapping

1. Convert thermal plant designations
2. Add renewable energy classifications
3. Implement grid interconnection codes
4. Establish maintenance boundaries

Phase 3: System Integration

1. Update control system configurations
2. Retrain operations personnel
3. Integrate with grid management systems
4. Implement condition monitoring

Power Industry Best Practices

1. Establish Clear Power System Boundaries

Define designation scope:

  • Generation systems and boundaries
  • Transmission interconnection points
  • Distribution interface requirements
  • Customer connection standards

2. Implement Consistent Electrical Classification

Power system examples:

Generation Systems:
=1GAA (Unit 1 Generator system)
=1STM (Unit 1 Steam system)
=1CON (Unit 1 Control system)

Electrical Systems:
=1ELE (Unit 1 Electrical system)
=1PRO (Unit 1 Protection system)
=AUX   (Auxiliary power systems)

3. Ensure Grid Code Compliance

Align with electrical standards:

  • IEEE power system standards
  • IEC electrical equipment codes
  • Regional grid code requirements
  • Utility interconnection standards

4. Train Operations Personnel

RDS-PS requires understanding of:

  • Multi-aspect power system designation
  • Grid integration requirements
  • Digital system interfaces
  • Modern maintenance approaches

Common Implementation Pitfalls

Pitfall 1: Mixing Generation and Transmission Codes

Problem: Using plant-specific codes for grid equipment Solution: Clear boundary definitions between generation and transmission

Pitfall 2: Inadequate Renewable Integration

Problem: Forcing solar/wind into thermal plant structures Solution: Use RDS-PS flexible designation for renewable technologies

Pitfall 3: Poor Grid Interface Definition

Problem: Unclear designation at interconnection points Solution: Establish clear grid boundary and ownership codes

ROI and Benefits for Power Systems

Power facilities implementing RDS-PS report:

Operational Benefits:

  • 25% faster equipment identification during outages
  • 30% improvement in maintenance planning efficiency
  • 40% better integration of renewable additions
  • 20% reduction in grid interconnection time

Digital Benefits:

  • Enhanced SCADA system performance
  • Improved predictive maintenance capabilities
  • Better grid stability monitoring
  • Streamlined regulatory reporting

The Future: RDS-PS and Smart Power Systems

RDS-PS is positioned for the digital power future:

Smart Grid Integration

Generation: =1GAA+10AA-G001
Grid Interface: =GRID+INT-PT001
Distribution: =DIST+FDR-CB001
Customer: =CUST+MTR-001

Advanced Power Analytics

Equipment: =1GAA+10AA-G001
Sensors: =1GAA+10AA-G001.TE01 (Temperature)
Analytics: =1GAA+10AA-G001.VIB (Vibration)
Predictions: =1GAA+10AA-G001.PDA (Predictive Analytics)

Conclusion: Powering the Future

The evolution from RDS-PP to RDS-PS represents a fundamental shift from traditional power plant thinking to modern electrical system management. While RDS-PP remains effective for conventional generation facilities, RDS-PS offers the flexibility and digital readiness required for today's diverse power systems.

Key Advantages of RDS-PS:

  1. Broader power system coverage - Beyond just generation
  2. Renewable energy ready - Native support for modern technologies
  3. Smart grid compatible - Digital system integration
  4. Grid-scale flexible - Transmission and distribution support
  5. Future-proof - Ready for next-generation power systems

For power industry organizations, the question isn't whether RDS-PS is better than RDS-PP – it's whether your electrical systems are ready to leverage the enhanced capabilities that RDS-PS provides for modern power infrastructure.


Need expert guidance on implementing RDS-PS for your power systems or migrating from RDS-PP? AssetStage provides specialized consulting and training on power system classification standards, including hands-on implementation support for generation, transmission, and renewable energy facilities. Contact our power systems team or explore our engineering standards services to ensure successful implementation.