Electrical Installation Standards for General and Individual Supply Lines

General Supply Lines

The general supply line links the main protection with the centralization of meters. It utilizes the following installation types:

• Cores inside embedded tubes
• Surface-mounted pipes
• Buried pipes
• Protective channels
• Ducting works designed for this purpose
• Busbar trunking

Note: Almost any driver will include the necessary protection.

Installation of LGA

The route must be as short and rectilinear as possible, utilizing areas of common usage. When installed in tubes, the outside diameter will depend on the cable section, ensuring 100% expansion capacity. Vertical installations should be placed in stairwells, with firewalls installed in garages every three floors.

LGA Cables

Cables consist of 3 phase wires, 1 neutral, and 1 protective conductor (copper or aluminum). These are unipolar, insulated, and rated for 1000 V (0.6 to 1 kV). The cables must be fire-retardant with reduced smoke emission and opacity. The section must be uniform throughout, with a minimum of 10mm² to 16mm² for copper and aluminum.

Calculation criteria:

• Maximum permissible intensity
• Voltage drop: 0.5% for fully centralized meters and 1% for partial centralization
• Power factor: 0.85
• Neutral section: 50% of the phase section

Individual Supply Lines

The individual supply line starts from the general supply and provides electricity to a user installation. It contains:

• Safety fuses
• Measurement set
• General control and protection devices

Installation of Individual Leads

Protective tubes and channels must have a section that allows for 100% expansion of the initially installed wire. The minimum nominal pipe diameter is 32mm to facilitate future upgrades. Pipe joints must be threaded and secured to prevent separation. When running vertically on fire-resistant walls, manhole boxes must be insulated and fire-retardant.

Individual Lead Wires

The number of conductors is determined by the power phases and the predictability of the installation. Each installation must include its corresponding neutral and protective conductor. Conductors are copper or aluminum with unipolar insulation (750 V, or 1000 V if using a hose). The minimum section is 6mm², with control threads calculated at 1.5mm² (red).

Calculation criteria:

• Power provided for each user
• Line length
• Voltage drop and conductivity
• Voltage drop limits: 0.5% for meters in more than one place, 1% for fully concentrated meters, and 1.5% for a unique user link.