Remote start/stop operations in SCADA systems - Step-by-Step Execution

Process Flow - Remote start/stop operations

Operator sends command

↓

Command received by SCADA

↓

Validate command

Yes No↓

Execute start/stop

↓

Update system status

↓

Send feedback to operator

The operator sends a start or stop command remotely. The SCADA system receives and checks it. If valid, it executes the command, updates status, and informs the operator.

Execution Sample

SCADA systems

send_command('start')
if validate_command('start'):
    execute_start()
    update_status('running')
    send_feedback('started')
else:
    send_feedback('invalid command')

This code sends a start command, validates it, executes start if valid, updates status, and sends feedback.

Process Table

Step	Action	Command	Validation Result	System Status	Feedback to Operator
1	Send command	start	N/A	idle	N/A
2	Validate command	start	Valid	idle	N/A
3	Execute command	start	Valid	running	N/A
4	Update status	start	Valid	running	N/A
5	Send feedback	start	Valid	running	started
6	End	N/A	N/A	running	started

💡 Command executed and feedback sent; system status updated to running.

Status Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 4	After Step 5	Final
command	None	start	start	start	start	start	start
validation	None	None	Valid	Valid	Valid	Valid	Valid
system_status	idle	idle	idle	running	running	running	running
feedback	None	None	None	None	None	started	started

Key Moments - 2 Insights

Why does the system status change only after validation?

The system status updates only after the command is validated as valid (see step 2 and 3 in execution_table). This prevents invalid commands from affecting the system.

What happens if the command is invalid?

If invalid, the command is rejected and feedback 'invalid command' is sent without changing system status. This is shown by the 'No' branch in concept_flow.

Visual Quiz - 3 Questions

Look at the execution table, what is the system status after step 3?

A stopped

B running

C idle

D unknown

💡 Hint

Check the 'System Status' column at step 3 in the execution_table.

At which step is feedback sent to the operator?

A Step 5

B Step 4

C Step 2

D Step 3

💡 Hint

Look at the 'Action' and 'Feedback to Operator' columns in the execution_table.

If the command was 'stop' instead of 'start', which variable would change in the variable_tracker?

A validation only

B feedback only

C command and system_status

D system_status only

💡 Hint

Refer to the 'command' and 'system_status' rows in variable_tracker and imagine the command value changed.

Concept Snapshot

Remote start/stop operations:
- Operator sends command remotely
- SCADA validates command
- If valid, executes start or stop
- Updates system status accordingly
- Sends feedback to operator
Always validate before execution to keep system safe.

Full Transcript

In remote start/stop operations, the operator sends a command to the SCADA system. The system first validates the command to ensure it is allowed. If the command is valid, the system executes it, updates the system status (like changing from idle to running), and sends feedback to the operator confirming the action. If the command is invalid, the system rejects it and informs the operator without changing the system status. This process ensures safe and controlled remote operation.