ITC12 Electrical Link Installations: Components and Schematics

ITC12: Electrical Link Installations

1.1. Definition

Link installations are defined as the electrical circuits that connect the utility's general protection box(es) with the user's indoor or receiving facilities. They begin at the end of the main service connection and terminate at the user's general command and protection devices.

These installations must always be located in common use areas and are the property of the user, who is responsible for their upkeep and maintenance.

1.2. Components of Link Installations

• General Protection Box (CGP): Houses the primary protection elements.
• General Power Supply Line (LGA): The main line feeding the building.
• Meter Location Equipment (CA): The assembly for housing the electrical meters.
• Individual Branch Circuit (DI): The circuit from the meter to the user's main panel.
• Power Control Switch Box (ICP): Contains the switch that limits maximum power consumption.
• General Command and Protection Devices (DGMP): The user's main switchboard for control and protection.

2. Schematics

Legend

• Distribution Network
• Weatherhead
• Overall Safety Protection
• General Power Supply Line
• Shunt Switch
• Junction Box
• Meter Location
• Individual Branch Circuit
• Safety Fuse
• Meter
• Power Control Switch Box
• General Control and Protection Devices
• Internal Installation

Note: All individual branch circuits and internal installations are private property.

2.1. For a Single User

In this case, the link installation can be simplified by combining the General Protection Box (CGP) and the metering equipment in the same location. This configuration eliminates the need for a General Power Supply Line (LGA). Consequently, the safety fuse (9) is the same as the fuse within the CGP.

Scheme 2.1: Single User Installation

2.2. For More Than One User

For multiple users, link installations must follow the schematics below, which vary depending on the placement of the meters.

2.2.1. Two Users Supplied from the Same Location

Scheme 2.1 can be generalized for two users supplied from the same location. Therefore, the information regarding the safety fuse (9) in section 2.1 also applies here.

Scheme 2.2.1: Two Users from the Same Source

2.2.2. Centralized Meters in a Single Location

This scheme is typically used in vertical or horizontal building complexes, such as residential buildings, commercial centers, offices, or industrial parks.

Scheme 2.2.2: Multiple Users with Centralized Meters

2.2.3. Centralized Meters in Multiple Locations

This scheme is used in large residential or commercial buildings, offices, or industrial parks where load forecasting makes it advisable to centralize meters in more than one location or on different floors. This setup is also used for multiple centralized locations on a single floor in large commercial or industrial buildings where the surface area and load forecast recommend it. It can also be applied to clusters of houses with horizontal distribution within a private enclosure.

This scheme is applicable for centralized metering distributed via busbar trunking systems that comply with the UNE-EN 60439-2 standard.

Scheme 2.2.3: Multiple Users with Multiple Centralized Meter Locations