Historian architecture overview in SCADA systems - Step-by-Step Execution

Process Flow - Historian architecture overview

Data Sources

↓

Data Collection Layer

↓

Data Storage Layer (Historian Database)

↓

Data Processing & Analytics

↓

User Interface & Reporting

↓

Decision Making & Control

Data flows from sources through collection, storage, processing, and finally to user interfaces for decision making.

Execution Sample

SCADA systems

Data Sources -> Data Collection -> Historian DB -> Analytics -> UI -> Control

Shows the flow of data through the main components of a historian architecture.

Process Table

Step	Component	Action	Data State	Output
1	Data Sources	Generate real-time data	Raw sensor data	Data sent to collection layer
2	Data Collection Layer	Receive and buffer data	Buffered data	Data forwarded to storage
3	Historian Database	Store time-series data	Stored historical data	Data available for queries
4	Data Processing & Analytics	Analyze stored data	Processed insights	Reports and alerts generated
5	User Interface & Reporting	Display data and reports	Visualized data	User views and interacts
6	Decision Making & Control	Use insights to act	Control commands	System adjustments made
7	End	Data cycle complete	N/A	Waiting for new data

💡 Data cycle completes after control actions; system waits for new data from sources.

Status Tracker

Component	Initial State	After Step 1	After Step 2	After Step 3	After Step 4	After Step 5	Final
Data	No data	Raw sensor data	Buffered data	Stored historical data	Processed insights	Visualized data	Control commands

Key Moments - 3 Insights

Why does data need buffering in the collection layer?

Buffering ensures no data is lost if the storage layer is busy; see execution_table step 2 where data is buffered before storage.

How does the historian database differ from regular databases?

It specializes in storing time-series data efficiently for fast retrieval, as shown in step 3 where data is stored as historical records.

What triggers the control actions in the system?

Processed insights from analytics (step 4) generate reports and alerts that lead to control commands in step 6.

Visual Quiz - 3 Questions

Look at the execution table, what is the data state after step 2?

A Stored historical data

B Buffered data

C Raw sensor data

D Processed insights

💡 Hint

Check the 'Data State' column for step 2 in the execution_table.

At which step does the system generate reports and alerts?

A Step 4

B Step 3

C Step 5

D Step 6

💡 Hint

Look for 'Reports and alerts generated' in the 'Output' column.

If data buffering was removed, which step would be directly affected?

A Step 1

B Step 3

C Step 2

D Step 5

💡 Hint

Buffering happens in the Data Collection Layer at step 2.

Concept Snapshot

Historian architecture moves data from sources through collection, storage, processing, and visualization.
Data buffering prevents loss before storage.
Historian DB stores time-series data efficiently.
Analytics generate insights for control.
User interfaces display data for decisions.

Full Transcript

The historian architecture overview shows how data flows from sources like sensors into a collection layer where it is buffered. Then data is stored in a historian database specialized for time-series data. After storage, data is processed and analyzed to produce insights, reports, and alerts. These outputs are shown in user interfaces for operators to view and interact with. Finally, control commands based on insights adjust the system. This cycle repeats continuously to support real-time monitoring and control.