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

Required: single-phase current and both line voltages.
Volts
Line-to-line volts

1 Phase To 3 Phase Formula

The following formula is used to convert between single-phase current I1ฯ† and three-phase current I3ฯ†.

Iโ‚3ฯ†) = (Iโ‚1ฯ†)) / (โˆš(3))

The inverse conversion is:

Iโ‚1ฯ†) = Iโ‚3ฯ†) 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, Iโ‚ƒฯ† โ‰ˆ Iโ‚ฯ† / โˆš3)
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 balanced three-phase system and equal apparent power: Iโ‚ƒฯ† โ‰ˆ Iโ‚ฯ† / 1.732. Actual currents depend on voltage and power factor.

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 steps outline how to convert between single-phase and three-phase currents using the formulas 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:

Convert a single-phase current of I1ฯ† = 150 A to the equivalent three-phase current.

Iโ‚3ฯ†) = (150) / (โˆš(3)) โ‰ˆ 86.604 A

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