fbpx
Breaking News
Home » AC Fundamentals » Power Formulas in DC, AC Single Phase & Three Phase Circuits.

Power Formulas in DC, AC Single Phase & Three Phase Circuits.

Power Formulas in DC, AC Single Phase and AC Three Phase Circuits

Back to basic, below are the simple Power formulas for Single Phase AC Circuit, Three Phase AC Circuits and DC Circuits. You can easily find electric power in watts by using the following power formulas in electric circuits.

Power Formulas in DC Circuits

  • P = V x I
  • P = I2 x R
  • P = V2 / R

Where:

P = Power in Watts

V = Voltage in Volts

I = Current in Amperes

R = Resistance in Ohms (Ω)

Power Formulas in Single Phase AC Circuits

  • P = V x I x Cos Ф
  • P = I2 x R x Cos Ф
  • P = V2 / R (Cos Ф)

Where:

P = Power in Watts

V = Voltage in Volts

I = Current in Amperes

R = Resistance in Ohms (Ω)

Cos Ф = Power Factor

Power Formulas in Three Phase AC Circuits

  • P = √3 x VL x IL x Cos Ф
  • P = 3 x VPh x IPh x Cos Ф
  • P = 3 x I2 x R x Cos Ф
  • P = 3 (V2 / R) x Cos Ф

Where:

P = Power in Watts

V = Voltage in Volts

I = Current in Amperes

R = Resistance in Ohms (Ω)

Cos Ф = Power Factor

Click image to enlarge

Power Formulas in DC, AC Single Phase and AC Three Phase Circuits

 

You may also read:

ETJLCPCB - Prototype 10 PCBs for $2 + 2 days Lead Time
China's Largest PCB Prototype Enterprise, 300,000+ Customers & 10,000+ Online Orders Per Day
Inside a huge PCB factory

About Electrical Technology

All about Electrical & Electronics Engineering & Technology. Follow , Facebook , Twitter , Instagram, Pinterest, YouTube, & Linkedin to get the latest updates or subscribe Here to get latest Engineering Articles in your mailbox.

Check Also

Short Circuit Currents faults And Symmetrical Components

Short Circuit Currents And Symmetrical Components

Short Circuit Currents And Symmetrical Components (Manuel Bolotinha) Short Circuit Faults and Currents Short-circuits can …

13 comments

  1. sir i want to know in detail about KVA

  2. The main reason is they don&#39;t stick long enough with a <br />new, good program. Many people are not really encouraged to do workouts if they are just in the gym listening to music or <br />watching TV as they walk away their fat in a treadmill.<br />These can be prepared in a healthy and satisfying way that will leave your stomach all fuzzy and warm.<br /><br /><br />Here is my web site – <a

  3. can you tell me about load calculation and size of wire depending on load

  4. Dear sir,
    i want to know about contactor relays its types rating wiring could you please help me in this matter.

  5. sir i want to know about single phase circuit. pls help me.

  6. dear i want to know about, why we rated prim-mover in MW (Mega-Watt) while our Generator rated in KVA………please tell me>.

    • this Answer KVA*.8=KW And KW/1000= Mega Watt

    • MOHAMED IQBAL MOOSA

      The out put of the Generator will change depending on the load power factor ,0.8, 0.9 or unity power factor which is only in lighting load also if capacitance load is their the KW OR MEGA WATT WILL BE MORE.

  7. In 45 kw ac drive, output motor consumes 30kw, then another how much dc current use in dc bus.
    Means what is the formula od dc current.

    Please help….

  8. Formula P=(I^2)*(R)*Cos(A) is wrong. Currect answer is P=(I^2)*R.

    P=3*(I^2)*(R)*Cos(A) is wrong. Currect answer is P=3*(I^2)*R.

Leave a Reply

Your email address will not be published. Required fields are marked *