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What is the formulae for a 3 phase circuit to calculate the power?
Wiki User
∙ 13y ago
watts = volts * amps * 1.73 * power factor
If the load is resistive, such as a heater or incandescent lamp, use 1.0 for power factor.
For reactive loads such as motors, the power factor is usually found on the nameplate.
Comment
More specifically, for a balanced load (and ONLY for a balanced load) power is the product of 1.73 and the line voltage and the line current and the power factor.
Wiki User
∙ 10y ago
Wiki User
∙ 14y agoThe formula is: HP= E(volts) X I(amps) X %EFF (efficiency) X PF (power factor) X 1.73 (the square root of 3) divided by 746 (number of watts in 1 HP).
The EFF and PF of the motor should be shown on the motor nameplate.
Wiki User
∙ 12y agoOne horse power for a electric motor is defined as 746 watts. Figure out how many watts each winding is pulling, assume they are balanced (they should be - if not, something is wrong), multiply by three, and then divide by 746.
Don't forget that power factor will enter into the calculation, so if you are measuring volt-amps instead of watts, then you will need to divide by the power factor (which is the cosine of the phase angle between voltage and current) in order to determine watts.
Wiki User
∙ 15y agoVolts X Amps X 1.73 = VA (Volt-Amperes) VA X PF (power factor) = Watts
Wiki User
∙ 11y agoWiki User
∙ 13y agoWatts = Amps x Volts x 1.73 x pf. pf is the power factor.
Wiki User
∙ 14y agoThe formula for any cable calculation is knowing what the load current is.
Wiki User
∙ 10y agoYour question is far too vague, as there are numerous formulae associated with three-phase motors.
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How you convert the value of single phase power to value of 3 phase power?
Electric power is measured in watts. It does not matter if it is single phase or three phase. All things being equal, for the same load, the power measured in a single phase circuit or a three phase circuit, will be the same.
How do you calculate the load percentage of a three phase UPS?
output power/Rated power
Why you take the conjugate of current in complex power?
In order to calculate the complex power of a circuit, the conjugate of current is used. The Vrms of the circuit is multiplied by the complex conjugate of the total circuit current.
What is the power factor on a circuit in resonance?
You are presumably referring to an 'R-L-C' circuit. At resonance, the load current is in phase with the supply voltage and, so, the power factor is unity.
How do you compute powe available on a 3 phase circuit?
Root 3 x voltage x current x power factor = power in watt
What is the formula for phase angle?
Phase angle is defined as the angle by which the load current leads or lags the supply voltage in an AC circuit. There are numerous ways to calculate a circuit's phase angle, so there is no 'formula' as such. For example, if you know a load's resistance and impedance, or its true power and apparent power, then you can use basic trigonometry to calculate the phase angle, and so on.
How you convert the value of single phase power to value of 3 phase power?
Electric power is measured in watts. It does not matter if it is single phase or three phase. All things being equal, for the same load, the power measured in a single phase circuit or a three phase circuit, will be the same.
Compare the phase relationship between the voltage and current in a purely resistive circuit and an RL circuit?
In a pure resistive circuit the voltage and current are in phase. In an inductive circuit they are fro zero to 180 degrees out of phase. If they are in phase the Power Factor is 1 and 180 degrees the PF is zero. The exact amount of the phase difference depends on the specific circuit.
Power factor for pure resistive circuit?
ratio between true power and apparent power is called the power factor for a circuit Power factor =true power/apparent power also we conclude PF=power dissipated / actual power in pure resistive circuit if total resistance is made zero power factor will be zero
How can a tuned RC circuit improve the power factor of an inductive motor circuit?
The RC circuit can reduce the phase shift between the voltage and current in the power line. The phase shift is caused by the inductance of the motor. The phase shift between the voltage and current in the power line causes problems due to the presence of so called imaginary current or power that does no work but must be supplied by the power source.
What is phase loss?
Phase loss is the loss of power to a specific area of the circuit. Phase loss can result from exposed wires or damaged wires or even downed power lines.
How to Calculate three phase watts with unbalanced phase current?
You will need to determine the power per phase, and add them up to give the total power of the three-phase load. To do this, you will need to multiply the phase-voltage by the phase current by the power factor -for each phase.
How do you calculate the load percentage of a three phase UPS?
output power/Rated power
Describe in brief the type of power factor improvement system?
You want a power factor of 1 or 100%, which is a purely resistive circuit. If you have a motor or some other inductive load in a circuit the total voltage and total current in the circuit will not be in phase (phase shift), your power factor will be less than 1. By adding a capacitor (180 degrees out of phase with inductive load) to the circuit that has a capacitive reactance equal to the inductive reactance of the motor, you can cancel the phase shift and have an ideal power factor (no wasted power). Anything above .9 would be good.
How do you calculate power consumption of 3 phase airconditioner unit?
From its nameplate data.
Why you take the conjugate of current in complex power?
In order to calculate the complex power of a circuit, the conjugate of current is used. The Vrms of the circuit is multiplied by the complex conjugate of the total circuit current.
What are the problems with switching AC currents in a circuit of pure resistance at unity power factor?
Power factor does not apply to a resistive circuit. Just the current will follow the voltage (in phase)
