Understanding electrical wire colours and proper wiring practices is crucial for safety and compliance when installing industrial equipment like an air compressor in France. France adheres to the international IEC 60446 standard, which is now harmonized across the European Union.
Part 1: French (EU) Electrical Wire Colour Codes (AC Power)
The wiring colours in France are standardized under NF C 15-100, which is the French electrical code aligned with EU standards.
Line (Phase) Wires: Carry the electrical voltage from the panel to the device.
Brown, Black, Grey: These are the colours for phase wires.
In a single-phase system, you will typically see Brown.
In a three-phase system, you will see Brown, Black, and Grey.
Neutral Wire: Completes the circuit and carries current back to the panel.
Blue: The neutral wire is always identified by this colour.
Ground (Earth / Protective Conductor) Wire: A critical safety wire that provides a path for fault current to earth, preventing electric shock.
Green-and-Yellow Stripe: This is the exclusive and mandatory colour for the protective earth wire. The two colours must always be used together.
Summary Table:
Crucial Safety Note: While these are the current harmonized standards (post-1970), older French installations might have different colour codes (e.g., Red for phase, Grey for neutral). You should ALWAYS verify with a multimeter and consult a qualified electrician (électricien).
Part 2: Air Compressor Wiring Connection Guide for France
Connecting a powerful machine like a 37KW ZAKF air compressor in France is a task that must be performed by a qualified and certified electrician to ensure safety and compliance with NF C 15-100.
Key Steps and Considerations:
1. Power Requirements:
A 37KW compressor is a high-power industrial machine.
Voltage & Frequency: In France, the standard is 230V ±10% for single-phase and 400V ±10% for three-phase, with a frequency of 50 Hz. A 37KW unit will almost certainly require a 400V, three-phase connection.
Current: At 37KW, the full-load current will be significant (e.g., ~67 Amps at 400V 3-phase). The wiring and circuit protection must be sized correctly for this load.
2. Disconnect and Circuit Protection:
A dedicated, lockable safety disconnect switch (disjoncteur) must be installed within sight of the compressor. This allows for quick power shutdown for maintenance (Lockout-Tagout procedures).
3. Cable and Conduit:
An electrician will select the correct cable type (e.g., HO7RN-F or other harmonized cable) and gauge (e.g., 16 mm² or larger, depending on distance) rated for the current and the industrial environment, installed in appropriate conduit or trunking.
4. Termination at the Compressor Motor:
The compressor's motor terminal box will have clear markings (L1, L2, L3, N, PE or the earth symbol ⏚).
The electrician will connect:
Brown (L1) to terminal L1
Black (L2) to terminal L2
Grey (L3) to terminal L3
Blue (N) to the neutral terminal (if required by the control circuit).
Green-and-Yellow (PE) to the designated grounding terminal (⏚).
5. Protection Devices:
The circuit will be protected by a circuit breaker sized for the motor's inrush current.
A Motor Starter with overload relays is mandatory to protect the motor from burning out due to excessive current or phase loss.
Residual-Current Device (RCD / Dispositif à courant différentiel - DDR): While not always mandatory for three-phase machines with specific insulation monitoring, it is a critical safety device often required to protect against earth leakage faults.
Summary of Best Practices:
Hire a Qualified Electrician: This is a legal and safety requirement in France. The electrician must be certified and familiar with NF C 15-100.
Comply with NF C 15-100: All work must comply with the French electrical code, which covers everything from wire sizing to the number of sockets per circuit. A Consuel certification may be required after installation.
Use the Manufacturer's Diagram: The wiring schematic provided by ZAKF is the final authority for connecting their specific compressor model.
Verify Voltage and Phase: Before installation, confirm that your facility's electrical service is 400V/50Hz 3-phase.
By understanding the French/EU colour codes and the regulatory complexity involved, you can ensure that your air compressor is installed safely, efficiently, and in full compliance with French standards.
