**What is motor Full Load Current**

Full Load Current is the maximum allowable current that is tolerated by the motor insulation. The input current to the machine exceeds the full load current means, the electrical machine may get damaged. Due to the excess current flow, the machine produces additional heat (Because of heat /loss =I^{2} R)., This may lead to damages to the insulation or winding of the electrical motor. Hence, Operating a machine below full load current increases the life span of the electrical motor. In this article, we will see motor full load current chart for 3 phase motor, single-phase motor, and direct motor.

As a “rules of thumb” amps horsepower rating can be estimated to

*110 volts*motor – single-phase :*14 amps/hp**220 volts*motor – single-phase :*8 amps/hp**220 volts*motor – 3-phase :*2.2 amps/hp**415 volts*motor – 3-phase :*1.3 amps/hp*

**Single-phase motor full load current chart**

The tables are based on motors of approximately 1500rpm of average efficiency and power factor. Motors of higher speed usually take a lower current than that shown in the table; while motors of lower speed usually take higher current. Wide variations from these figures can arise, especially on single-phase motors, and engineers should, whenever possible, determine the actual full load current from the motor rating plate.

single-phase full load current chart is as follow :

Load in KW | Load in hp | 110V AC(In amp) | 220V AC(In amp) | 240V AC(In amp) |

0.07 kW | 1/12 | 2.4 A | 1.2 | 1.1 |

0.1 kW | 1/8 | 3.3 | 1.6 | 1.5 |

0.12 kW | 1/6 | 3.8 | 1.9 | 1.7 |

0.18 kW | 1/4 | 4.5 | 2.3 | 2.1 |

0.25 kW | 1/3 | 5.8 | 2.9 | 2.6 |

0.37 kW | 1/2 | 7.9 | 3.9 | 3.6 |

0.56 kW | 3/4 | 11 | 5.5 | 5 |

0.75 kW | 1 | 15 | 7.3 | 6.7 |

1.1 kW | 1.5 | 21 | 10 | 9 |

1.5 kW | 2 | 26 | 13 | 12 |

2.2 kW | 3 | 37 | 19 | 17 |

3 kW | 4 | 49 | 24 | 22 |

3.7 kW | 5 | 54 | 27 | 25 |

4 kW | 5.5 | 60 | 30 | 27 |

5.5 kW | 7.5 | 85 | 41 | 38 |

7.5 kW | 10 | 110 | 55 | 50 |

**3 phase motor full load current chart**

The following chart is the full load current chart for 3 phase motor :

kW | HP | 220V AC(In amp) | 240V AC(In amp) | 380V AC(In amp) | 415V AC(In amp) | 550V AC(In amp) | 660V AC(In amp) | 690V AC(In amp) |

0.1 | 1/8 | 0.32 | 0.30 | 0.19 | 0.17 | 0.13 | 0.11 | 0.10 |

0.18 | ¼ | 0.58 | 0.53 | 0.34 | 0.31 | 0.23 | 0.19 | 0.19 |

0.25 | 1/3 | 0.81 | 0.74 | 0.47 | 0.43 | 0.32 | 0.27 | 0.26 |

0.37 | ½ | 1.19 | 1.10 | 0.69 | 0.63 | 0.48 | 0.40 | 0.38 |

0.56 | ¾ | 1.81 | 1.66 | 1.05 | 0.96 | 0.72 | 0.60 | 0.58 |

0.75 | 1 | 2.42 | 2.22 | 1.40 | 1.28 | 0.97 | 0.81 | 0.77 |

1.1 | 1.40 | 3.55 | 3.26 | 2.06 | 1.88 | 1.42 | 1.18 | 1.13 |

1.5 | 2 | 5 | 4 | 3 | 3 | 2 | 2 | 2 |

2.2 | 3 | 7 | 7 | 4 | 4 | 3 | 2 | 2 |

3 | 4 | 10 | 9 | 6 | 5 | 4 | 3 | 3 |

3.7 | 5 | 12 | 11 | 7 | 6 | 5 | 4 | 4 |

4 | 5 | 13 | 12 | 7 | 7 | 5 | 4 | 4 |

5.5 | 7 | 18 | 16 | 10 | 9 | 7 | 6 | 6 |

7.5 | 10 | 24 | 22 | 14 | 13 | 10 | 8 | 8 |

9.3 | 12 | 30 | 28 | 17 | 16 | 12 | 10 | 10 |

10 | 13 | 32 | 30 | 19 | 17 | 13 | 11 | 10 |

11 | 14 | 36 | 33 | 21 | 19 | 14 | 12 | 11 |

15 | 19 | 48 | 44 | 28 | 26 | 19 | 16 | 15 |

18 | 23 | 58 | 53 | 34 | 31 | 23 | 19 | 19 |

22 | 28 | 71 | 65 | 41 | 38 | 28 | 24 | 23 |

30 | 38 | 97 | 89 | 56 | 51 | 39 | 32 | 31 |

37 | 47 | 119 | 110 | 69 | 63 | 48 | 40 | 38 |

45 | 57 | 145 | 133 | 84 | 77 | 58 | 48 | 46 |

55 | 70 | 178 | 163 | 103 | 94 | 71 | 59 | 57 |

75 | 95 | 242 | 222 | 140 | 128 | 97 | 81 | 77 |

90 | 115 | 291 | 266 | 168 | 154 | 116 | 97 | 93 |

110 | 140 | 355 | 326 | 206 | 188 | 142 | 118 | 113 |

130 | 165 | 420 | 385 | 243 | 223 | 168 | 140 | 134 |

150 | 191 | 484 | 444 | 280 | 257 | 183 | 161 | 154 |

**Direct Motor current full load chart** ( **FLA**)

For direct motor full load current chart is as follow :

Power (hp) | Power (kW) | FOR 230 V DCCurrent (A) | FOR 440 V DC Current (A) |

1/4 | 0.19 | 0.81 | 0.42 |

1/3 | 0.25 | 1.1 | 0.56 |

1/2 | 0.37 | 1.6 | 0.85 |

3/4 | 0.56 | 2.4 | 1.3 |

1 | 0.75 | 3.2 | 1.7 |

1.5 | 1.1 | 4.9 | 2.5 |

2 | 1.5 | 6.5 | 3.4 |

3 | 2.2 | 9.7 | 5.1 |

5 | 3.7 | 16 | 8.5 |

7.5 | 5.6 | 24 | 13 |

10 | 7.5 | 32 | 17 |

15 | 11 | 49 | 25 |

20 | 15 | 65 | 34 |

30 | 22 | 97 | 51 |

50 | 37 | 162 | 85 |

75 | 56 | 243 | 127 |

100 | 75 | 324 | 170 |

**Formula** for Full load current calculation of AC motors

**Formula**for Full load current calculation of AC motors

Formula used for full load current calculation of AC motors are as follow-

**Single Phase AC Motor Full load current (Amperes) = (P [kW] × 1000) / (V × cos ϕ)**

**Single Phase AC Motor FLC (Amperes) = (P [HP] × 746) / (V × cos ϕ × η)**

**Three Phase AC Motor FLC (Amperes) = (P [kW] × 1000) / (V × 1.732 × cos ϕ)**

**Three Phase AC Motor FLC (Amperes) = (P [HP] × 746) / (V × 1.732 × cos ϕ × η)**

*Where:*

**P [HP] , P [kW]** = Motor power rating (HP or kW),

**V** = Motor rated voltage (Volts),

**η** = Motor efficiency for example – 0.90,

**cos ϕ** = Motor power factor,

**1000** = Conversion factor to convert kW to W,

**746** = Conversion factor to convert HP to W.

## 3 phase motor amps calculation & formula

To Find… | Direct Current | Alternating Current (Single Phase) | Alternating Current(Two-Phase* Four-Wire | Alternating Current(Three Phase) |

Amperes when Horsepower is known | HP x 746 ──────── E x EFF | HP x 746 ──────── E x EFF x PF | HP x 746 ──────── 2 x E x EFF x PF | HP x 746 ─────────── E x EFF x PF x 1.73 |

Amperes when Kilowatts are known | KW x 1000 ──────── E | KW x 1000 ──────── E x PF | KW x 1000 ──────── 2 x E x PF | KW x 1000 ─────────── E x PF x 1.73 |

Amperes when “KVA” is known | ─ | KVA x 1000 ──────── E | KVA x 1000 ──────── 2 x E | KVA x 1000 ─────────── E x 1.73 |

Kilowatts | E x I ──────── 1000 | E x I x PF ──────── 1000 | I x E x 2 x PF ──────── 1000 | E x I x 1.73 x PF ─────────── 1000 |

Kilovolt-Amperes “KVA” | ─ | I x E ──────── 1000 | I x E x 2 ──────── 1000 | E x I x 1.73 ──────── 1000 |

Horsepower (Output) | E x I x EFF ──────── 746 | E x I x EFF x PF ──────── 746 | I x E x 2 x EFF x PF ─────────── 746 | E x I x EFF x PF x 1.73 ─────────── 746 |

Where E = Voltage, I = Amps, PF = Power Factor, EFF = Efficiency, HP = Horsepower

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