How much current can a 1 mm wire carry?
Then according to this algorithm we know: copper wire per 1 square millimeter area, if the 220V is used in single-phase circuit, it can safely carry the load current through the 1KW; if used in three-phase balanced load (such as motor) circuit, can safe current carrying load by 2.5KW.
How many watts can a 1.5 mm cable take?
Choosing the correct size cable

Conductor Size | Current | Maximum power (Watts) |
---|---|---|
1.0 mm2 | 10 amps | Up to 2400 Watts |
1.25 mm2 | 13 amps | Up to 3120 Watts |
1.5 mm2 | 15 amps | Up to 3600 Watts |
2.5 mm2 | 20 amps | Up to 4800 Watts |
How do I calculate what size wire I need?
How do I calculate wire size for motors?
- Multiply the resistivity (Ω•m) of the conductor material by the peak motor current (A), the number 1.25, and the total length of the cable (m).
- Divide the result by the voltage drop from the power source to the motor.
- Multiply by 1,000,000 to get the result in mm2.
How do you calculate the current carrying capacity of a wire?
Cable Capacity
- For Cu Wire Current Capacity (Up to 30 Sq.mm) = 6X Size of Wire in Sq.mm. Ex.
- For Cable Current Capacity = 4X Size of Cable in Sq.mm, Ex. For 2.5 Sq.mm = 4×2.5 = 9 Amp.
- Nomenclature for cable Rating = Uo/U.
- where Uo = Phase-Ground Voltage, U = Phase-Phase Voltage, Um = Highest Permissible Voltage.
What is 1.5 mm wire used for?

You will find twin core and earth cabling used all over your home in a variety of sizes. 2.5mm is commonly used for behind sockets, while 1-1.5mm is most often used for lights (depending on how many lights you have in a circuit).
What current CAN 0.5 mm cable carry?
Choosing the correct size flex
Conductor Size | Current | Maximum power (Watts) |
---|---|---|
0.5 mm2 | 3 amps | Up to 720 Watts |
0.75 mm2 | 6 amps | Up to 1440 Watts |
1.0 mm2 | 10 amps | Up to 2400 Watts |
1.25 mm2 | 13 amps | Up to 3120 Watts |
What is the current-carrying capacity of 1.5 sq mm copper wire?
Ambient Temperature: 30°C Conductor Operating Temperature: 90°C
Conductor cross-sectional area | Reference Method A (enclosed in conduit in thermally insulating wall etc.) | Reference Method C (clipped direct) Spaced by one cable diameter |
---|---|---|
(mm2) | (A) | (A) |
1 | 14 | 17.5 |
1.5 | 19 | 23 |
2.5 | 26 | 31 |
Can you mix 1mm and 1.5 mm cable?
IET Forums – Mixing cable sizes. So it’s ok even if I have wired half of the circuit in 1.5 and then do the rest in 1mm. Yes, mixed cable sizes are fine provided that the smallest cable is compliant for the size and type of OCPD. AND that the voltage drop for the entire circuit is within acceptable limits.