Industrial Plugs and Sockets: Reading Colour Codes and IP Ratings

Industrial plugs and sockets, built to the IEC 60309 standard, are designed so the wrong plug can't go into the wrong socket. Knowing the colour codes and ratings helps you order the right part the first time.

Colour tells you the voltage

  • Yellow: 100–130 V, common for site tools in some countries.
  • Blue: 200–250 V, single-phase.
  • Red: 380–480 V, typically three-phase.

Always confirm the voltage on the product itself: colour is a guide, and site-specific systems vary.

Pins and current rating

The number of pins tells you the configuration. For example, 3 pins (live, neutral, earth) for single-phase, and 4 or 5 pins for three-phase with or without neutral. Common current ratings are 16 A, 32 A, 63 A and 125 A. The plug, socket and cable must all match the circuit's rating.

IP rating: protection against dust and water

The IP code has two digits. The first is protection against solids, the second against water.

  • IP44: protected against splashing water. Suitable for sheltered or indoor use.
  • IP67: dust-tight and protected against temporary immersion. The right choice for outdoor sites, wash-down areas and marine decks.

Special environments

A note on installation

Electrical work in Singapore must be carried out by a licensed electrical worker. Check the manufacturer's datasheet for ratings and installation requirements.

How Delight can help

Browse Heavy-Duty Industrial Plugs & Sockets, Circuit Breakers & Panels and Electrical & Wiring. Send us your schedule or BOQ, and we'll quote the full set with datasheets within 24 hours. Request a quotation.

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