Calculate equivalent single-phase or balanced three-phase current and power from line voltage, power factor, and optional conversion efficiency.

Use single-phase input power and converter efficiency.

Balanced steady-state power comparison. Optional defaults assume unity power factors and 100% efficiency; enter actual equipment values when known.

Power factor and efficiency (optional)

0 < PF โ‰ค 1. Ideal default: 1.

0 < PF โ‰ค 1. Ideal default: 1.

0 < efficiency โ‰ค 100. Ideal default: 100%.

1 Phase To 3 Phase Formula

The shortcut below compares single-phase current I1ฯ† and balanced three-phase line current I3ฯ† only at equal RMS voltages, equal power factors and 100% conversion efficiency. Three-phase voltage is line-to-line voltage.

I3ฯ† = (I1ฯ†) / (โˆš(3))

The general power comparison is Pโ‚ = Vโ‚Iโ‚PFโ‚, Pโ‚ƒ = โˆš3 Vโ‚ƒIโ‚ƒPFโ‚ƒ, and Pโ‚ƒ = ฮทPโ‚. Therefore Iโ‚ƒ = Vโ‚Iโ‚PFโ‚ฮท / (โˆš3 Vโ‚ƒPFโ‚ƒ), where ฮท is efficiency as a fraction. Use the appropriate true power factors for the input and output. This steady-state comparison does not select equipment, wiring or protection; follow the manufacturerโ€™s ratings and qualified electrical design.

The inverse shortcut under the same ideal conditions is:

I1ฯ† = I3ฯ† ร— โˆš(3)

Variables:

  • I1ฯ† is the single-phase current in amperes (A).
  • I3ฯ† is the three-phase current in amperes (A).
  • โˆš3 is the square root of 3 (approximately 1.732).
Single-Phase to Three-Phase Current Conversion Table (Balanced, equal voltages and power factors, 100% efficiency)
Single-Phase Current (A) Three-Phase Current (A)
0.50.289
10.577
21.155
31.732
52.887
7.54.330
105.774
126.928
158.660
169.238
2011.547
2514.434
3017.321
4023.094
5028.868
6034.641
7543.301
8046.188
10057.735
12572.169
Assumes a balanced three-phase system, equal RMS voltages, equal power factors and 100% efficiency: Iโ‚ƒฯ† โ‰ˆ Iโ‚ฯ† / 1.732. Actual currents also depend on converter efficiency.

What is 1 Phase To 3 Phase?

Single-phase and three-phase are types of AC power systems. Single-phase delivers power through one alternating voltage waveform, while three-phase uses three waveforms, each 120ยฐ apart. Converting between single-phase and three-phase currents is important when designing or analyzing electrical systems to ensure proper load balancing and equipment sizing.

How to Calculate 1 Phase To 3 Phase?

The following shortcut steps assume equal voltages, equal power factors, a balanced load and ideal conversion. For different conditions, enter the voltages, power factors and efficiency in the calculator above.

  1. Identify the known current: either I1ฯ† or I3ฯ†.
  2. Select the appropriate formula:
    • If you know I1ฯ†, use I3ฯ† = I1ฯ† / โˆš3.
    • If you know I3ฯ†, use I1ฯ† = I3ฯ† ร— โˆš3.
  3. Plug the known current into the formula and calculate the missing current.
  4. Check your input and result with the calculator above.

Example Problem:

At equal voltages, equal power factors and 100% efficiency, convert a single-phase current of I1ฯ† = 150 A to the equivalent balanced three-phase line current.

I3ฯ† = (150) / (โˆš(3)) โ‰ˆ 86.603 A

Therefore, the three-phase current is approximately 86.60 A.