Main Panel is called the Main Distribution Board or MDB is the primary hub that connects the facility to the power source. It acts as the "master controller". It receives high-capacity power directly from a utility transformer or generator and divides it into smaller, safer circuits to feed sub-panels or large equipment.
The international standard for low voltage (LV) main panels is the IEC 61439 series. This standard replaced the older IEC 60439 series to provide clearer definitions of responsibilities and more rigorous testing procedures.
For an LV Main Distribution Board (MDB), the standard is split into two primary parts: IEC 61439-1 (General Rules): This provides the fundamental requirements, definitions, and verification framework applicable to all types of LV assemblies.
IEC 61439-2 (Power Switchgear and Controlgear Assemblies): This is the product standard specifically for main distribution boards, motor control centers (MCCs), and large power panels.
Sub Main Distribution Boards (SMDBs) are governed by the same international standards as Main Distribution Boards: the IEC 61439 series.
IEC 61439-2 (Power Switchgear and Controlgear Assemblies): This is the most common standard for SMDBs in industrial and commercial environments. It applies to panels operated by “instructed or skilled persons” and covers high-performance requirements like short-circuit withstand and temperature rise.
Internal Separation: Often specified as Form 2b for sub-panels to isolate busbars from functional units, enhancing safety.
Motor Control Center (MCC) or Motor Control Panel is a specialized assembly designed to start, stop, and protect electric motors. While a standard distribution board just provides power, an MCC provides functional control. It manages the heavy “inrush” current of motors during startup and monitors their performance to prevent burnouts or mechanical failures.
Key Functions
Motor Starting methods such as DOL (Direct-On-Line), Star-Delta, or Variable Speed Drives (VFDs) for smooth acceleration.
Overload Protection:
Uses Thermal Overload Relays or electronic sensors to trip the circuit if the motor draws too much current (e.g., if a pump is jammed).
Remote Automation:
Integrates with PLCs (Programmable Logic Controllers) or Building Management Systems (BMS) to allow motors to be controlled automatically based on pressure, flow, or temperature.
In high-end Schneider systems like BlokSeT or Okken, the MCC is made of withdrawable units (drawers). This allows a technician to pull out a single motor’s control module for repair without shutting down the rest of the factory.
It is a long established fact that a reader will be distracted by the readable content of a page.
It is a long established fact that a reader will be distracted by the readable content of a page.
It is a long established fact that a reader will be distracted by the readable content of a page.
It is a long established fact that a reader will be distracted by the readable content of a page.
It is a long established fact that a reader will be distracted by the readable content of a page.
It is a long established fact that a reader will be distracted by the readable content of a page.
It is a long established fact that a reader will be distracted by the readable content of a page.
It is a long established fact that a reader will be distracted by the readable content of a page.