Concept

1 My understanding is

When designing a Switchboard, the objectives can be prioritized based on importance :

1. Distribution → Ensuring that all equipment receives a proper power supply.
2. Protection → Preventing short circuits, overloads, and leakage currents to guarantee safety.
3. Control → Enabling equipment to operate as required and facilitating automation management.
4. Measurement & Monitoring → Tracking data, optimizing power usage, and improving efficiency.
5. Fault Isolation → Localizing issues to prevent them from affecting the entire system.

By structuring the design based on these functional requirements, we can select the appropriate components (circuit breakers, relays, PLCs, meters, etc.) and optimize the Switchboard layout and functionality accordingly!

2 Typical example

                           High Voltage Supply (11kV / 33kV)
                                      │
                                      ▼
                           ┌──────────────────────┐
                           │  Step-Down Transformer │ (HV to LV: 400V / 230V)
                           └──────────────────────┘
                                      │
                                      ▼
                          ┌──────────────────────┐
                          │   Main Switchboard (MSB) │
                          │  - Main Circuit Breaker (MCB) │
                          │  - Power Factor Correction (PFC) │
                          │  - PLC (Load Management) │
                          │  - SCADA Monitoring │
                          └──────────────────────┘
                                      │
       ┌──────────────────────────────┴──────────────────────────────┐
       │                                   │                                    │
       ▼                                   ▼                                    ▼
┌────────────────────┐      ┌────────────────────┐                ┌────────────────────┐
│  Sub Switchboard (SSB1)  │      │  Sub Switchboard (SSB2) │      │  Sub Switchboard (SSB3) │
│  - Distribution Circuits │      │  - Machine Controls     │      │  - Lighting & HVAC    │
│  - MCCB/MCB Protection   │      │  - Motor Control Center │      │  - IT & Office Loads  │
└────────────────────┘      └────────────────────┘                └────────────────────┘
       │                                   │                                    │
       ▼                                   ▼                                    ▼
┌────────────────────┐      ┌────────────────────┐                ┌────────────────────┐
│  Machine Control Panel  │      │  Equipment Control Panel  │      │  Facility Control Panel  │
│  - PLC for Automation   │      │  - Local Load Management  │      │  - SCADA Integration     │
│  - Sensors & Actuators  │      │  - Relays & Contactors    │      │  - Fire & Safety Systems │
└────────────────────┘      └────────────────────┘                └────────────────────┘

Explanation

• High Voltage Supply (11kV / 33kV) → Main power source from the utility company.
• Step-Down Transformer → Converts high voltage (HV) to low voltage (LV) suitable for industrial use.
• Main Switchboard (MSB) → Distributes power and includes protection, control, and monitoring.
  • Main Circuit Breaker (MCB) → Primary protection from faults.
  • Power Factor Correction (PFC) → Optimizes efficiency.
  • PLC (Load Management) → Manages power distribution and automation.
  • SCADA Monitoring → Tracks system performance.
• Sub Switchboards (SSB1, SSB2, SSB3) → Divides power into different areas (Production, Machines, HVAC, IT, etc.).
• Control Panels → Handle local equipment management, automation, and safety.