​Can a 30KW motor located 150 meters away be driven by a 16-square-millimeter wire?

To determine whether a 16-square-millimeter wire can drive a 30kW motor at a distance of 150 meters,

it is necessary to analyze from three aspects: **current calculation**, **wire current-carrying capacity**,

and **voltage drop**: ### I. Calculation of the operating current of the motor Assume it is a **three-phase 380V motor**, with a power factor of \( \cos\phi = 0.85 \) and an efficiency of

\( \eta = 0.9 \), then the current is: \[ I = \frac{P}{\sqrt{3} \times U \times \cos\phi \times \eta} = \frac{30000}{1.732 \times 380 \times 0.85 \times

0.9} \approx 60 \, \text{A} \] ### II. Current-carrying capacity of a 16-square-millimeter copper wire - **Current-carrying capacity for open wiring**: The current-carrying capacity of a 16-square-millimeter

copper wire at room temperature is approximately **80-100A** (specifically, it needs to refer to the cable

type and the wiring method). - **Conclusion**: The current-carrying capacity (above 80A) is **greater than the motor current (60A)**,

meeting the current-carrying requirement. ### III. Calculation of the voltage drop The allowable voltage drop is **5% of the rated voltage** (that is, \( 380 \times 5\% = 19 \, \text{V} \)). The resistivity of copper is \( \rho = 1.72 \times 10^{-8} \, \Omega·m \), and the resistance of the wire is: \[ R = \rho \times \frac{2L}{S} = 1.72 \times 10^{-8} \times \frac{2 \times 150}{16 \times 10^{-6}} \approx

0.32 \, \Omega \] The voltage drop is: \[ \Delta U = I \times R = 60 \times 0.32 = 19.2 \, \text{V} \] **Result**: The voltage drop is **close to the critical value of 19V** and barely meets the requirement,

but there are the following risks: 1. When the ambient temperature rises or when it is wired through a pipe, the current-carrying capacity

decreases, and the voltage drop may exceed the standard. 2. When the motor starts, the current is 4-7 times the rated current (approximately 240-420A), and the

instantaneous voltage drop will be even greater, which may lead to starting failure. ### IV. Suggested solutions

### Final conclusion - **For short-term temporary use**: A 16-square-millimeter copper wire is barely feasible, but the

voltage stability needs to be monitored. - **For long-term stable operation**: **It is recommended to upgrade to a 25-square-millimeter

copper wire** to ensure that the voltage drop is less than 19V and to be able to cope with the

impact of the starting current.