3/29 Electric Wire
The 3/29 wire (~1.25-1.5 mm²) is engineered for low-load residential loops. It safely carries a 10-13A current capacity, making it the standard choice for lighting and ceiling fans.
Specifications
Technical data sourced from official brand documentation and engineering standards.
| Metric Equivalent | 1.25-1.5 mm² |
| Safe Current Capacity | ~13 Amps |
| Max Resistance (at 20°C) | 14.03 Ω/km |
| Standard Voltage Grade | 250/440 V |
| Engineering Standard | BS 2004 / BS 6004 |
| Copper Purity | 99.90% |
Description
3/29 Wire: Technical Specifications
The 3/29 electrical cable is a standard imperial-sized wire. When evaluating the market for this cable, understanding its physical structure is critical. The naming convention refers to its core construction: it consists of exactly 3 solid copper strands, with each individual strand measuring 0.029 inches in diameter. For modern electrical engineering reference, the 3/29 wire size in mm is recognized as the equivalent to a 1.25 mm² to 1.5 mm² metric cable.
Usability & Core Applications
The 3/29 wire is engineered strictly for light-duty, low-load domestic wiring. Its primary usability includes:
- Lighting Circuits: Supplying power to LED panels, energy savers, and standard light bulbs across residential rooms.
- Ventilation Systems: Wiring for ceiling fans, bracket fans, and exhaust fans.
- Low-Power Sockets: Connecting standard 5-ampere wall sockets intended for small electronics like mobile chargers, Wi-Fi routers, and televisions.
- Usage Limitation: Due to its specific gauge, it must never be used for power-intensive appliances. It cannot handle the startup or running current of air conditioners, water heaters, irons, or refrigerators.
Load and Current Capacity Benchmark
Electrical safety depends on not exceeding the thermal limits of the copper conductor and its PVC insulation. The 3/29 wire current capacity is generally rated to safely carry between 10 to 13 Amperes continuously in standard conduit installations.
Translated into practical power metrics, the 3/29 wire load capacity in watts is approximately 2,200W to 2,800W on a standard 220V domestic supply. Exceeding this 3.29 wire load capacity will result in overheating, insulation melting, and potential electrical fires.
Standard Dimensions & Coil Sizing
To ensure accurate estimations for housing projects, contractors must verify the length of the cable provided by manufacturers. In the local market, the standard 3/29 wire coil length is benchmarked at exactly 90 meters per roll. Always verify this measurement, as non-compliant or cheaper alternatives often reduce the coil length to cut costs.
Frequently Asked Questions
What is meant by 3/29 wire?
It refers to the physical construction of the electrical cable. The "3" indicates that the cable contains three individual copper strands, while the "29" signifies that each of those strands has a diameter of 0.029 inches.
Where is 3/29 wire most commonly used in a house?
It is the standard engineering choice for basic lighting circuits, ceiling fans, doorbells, and low-power 5A switch sockets in residential wiring.
Can I use a 3/29 wire for a 1.5-ton air conditioner?
No. A 3/29 wire cannot handle the high startup and continuous current drawn by an air conditioner. Using it for an AC will cause overheating, melt the insulation, and create a severe fire hazard. Heavy appliances require thicker cables, such as 7/29 or 7/36.
