“On large construction projects, the main switchgear is responsible for distributing and controlling electrical power to various systems and equipment. The specific types and configurations of main switchgear can vary depending on the project’s size, complexity, and requirements. Here is a list of some common types of main switchgear found on large construction projects:

Main Distribution Board (MDB): The MDB is the primary distribution point for electrical power entering a building or facility. It receives power from the main supply and distributes it to different sub-distribution boards.

Sub-Distribution Board (SDB): SDBs receive power from the MDB and further distribute it to various sections or floors of a building or different parts of the construction site.

Motor Control Center (MCC): The MCC is a centralized panel that controls and protects electric motors used in various applications like pumps, fans, compressors, and conveyor systems.

Power Control Center (PCC): The PCC is a centralized panel used to control and monitor power distribution to different loads and equipment within a facility.

Automatic Transfer Switch (ATS): ATS is a critical component that automatically switches between primary and backup power sources in case of power failure, ensuring uninterrupted power supply to essential systems.

Generator Control Panel (GCP): This panel is used to monitor and control power distribution from generators, ensuring a smooth transfer of power from the generator to the facility’s electrical system.

Feeder Pillar: Feeder pillars are outdoor enclosures housing circuit breakers and protection devices, used for distributing power to various outdoor loads like lighting, pumps, and outdoor equipment.

Ring Main Unit (RMU): RMUs are used in secondary distribution systems to provide ring-type networks, offering more reliable power supply and reducing downtime during faults.

Gas Insulated Switchgear (GIS): GIS is a compact switchgear system that uses a gas (usually SF6) to insulate and extinguish electrical arcs, suitable for locations where space is limited.

Air Insulated Switchgear (AIS): AIS is switchgear that uses air as the insulation medium, often found in outdoor applications or large substations.

Low Voltage (LV) Switchgear: LV switchgear is used for electrical distribution at voltages typically up to 1000V.

Medium Voltage (MV) Switchgear: MV switchgear is used for electrical distribution at voltages from 1kV to 36kV.

High Voltage (HV) Switchgear: HV switchgear is used for electrical distribution at voltages above 36kV, often found in large substations and power transmission systems.

Control Panels: Besides main switchgear, various control panels are used to operate and monitor specific systems like lighting, HVAC (Heating, Ventilation, and Air Conditioning), fire alarms, and security systems.

Please note that the specific setup and nomenclature may vary from one project to another and also from country to country, but these are some of the main switchgear commonly encountered on large construction projects.”