SCL
Substation Configuration Language — the XML engineering description language defined in IEC 61850-6 that makes multi-vendor 61850 substations tractable.
Also: Substation Configuration Language, SCD, ICD, IID, SSD, CID
SCL is the XML engineering description language defined in IEC 61850-6. It is what makes multi-vendor IEC 61850 substations tractable — every IED, every data object, every GOOSE and Sampled Values subscription is described in SCL files that flow through the engineering tool-chain.
The whole substation exists as an XML file before it exists as steel.
File types
| Type | Stands for | Produced by | Purpose |
|---|---|---|---|
| ICD | IED Capability Description | Vendor | What this IED model can do |
| IID | Instantiated IED Description | Project | A specific IED’s configuration in this project |
| SSD | System Specification Description | System engineer | Single-line diagram, logical node allocation, vendor-neutral |
| SCD | Substation Configuration Description | Integrator | The full integrated project — SSD plus all IIDs |
| CID | Configured IED Description | Integrator | The final per-IED file loaded onto each device |
The flow is: vendors ship ICDs → system engineer drafts the SSD → integrator merges them into an SCD → CIDs are extracted and loaded.
Why it matters
Inadequate SCL engineering is one of the most common causes of commissioning delays in IEC 61850 projects. Edition mismatches between vendor tools (an SCD built in Edition 2.0 may not import cleanly into an Edition 1.0 tool, and vice versa) are a real source of integration friction.
The SCL tool-chain is the engineering substrate the substation depends on. When the SCD is wrong, the breakers don’t know what to trip on.