about power factor

Discussion in 'Homework Help' started by papa, May 22, 2005.

  1. papa

    Thread Starter New Member

    May 22, 2005
    a small factory has the following loads operating from the 240vrms 50 Hz supply

    (a) Forty 50 watts incandescent lamps with unity power factor
    (B) Thirty-five 40 watts flouorescent lamps with a lagging power of 0.9
    © One 3500 watts air conditioning system with a lagging power of 0.65

    Draw the complet phasor diagram and determine
    (i) the total peak current drawn
    (ii) the overall power factor of the factory

    actually,, i don't understand what can i do..
    A case of them (a),(B), and © finds the total peak current and drawn.???
    and.. power factor of the factory??

    power factor = true power / apparent power

    (a) power factor = 40*50 /240v
    = 8.3

    any body help me !!! please,,,
  2. milee


    Sep 20, 2007
    well as far as i know....power factor is the cosine angle between the voltage and the current....
    i think i didnt get u question properly....
    well if u want to increase ur power then u can join a capacitor // to ur supply then i guess it works...
    its because the combination of the capacitor in ur circuit...the angle betwwen the voltage n the current wud decrease hence we wud be improvin the power factor...as a consequence we get maximum of the real power
  3. recca02

    Senior Member

    Apr 2, 2007
    i didnt get the question either,
    are these two loads under two different cases or are they in parallel.
    again is AC in series with the lamps?.are these lamps in series or parallel?

    you might have to find out the total resultant impedance.
    once that is found the current and total power factor are easily known.
  4. cumesoftware

    Senior Member

    Apr 27, 2007
    I presume that all those loads are in parallel.
  5. recca02

    Senior Member

    Apr 2, 2007
    :rolleyes:oh look at the date of OP.
    i didnt knew about that and i was waiting for a reply.:p

    ok let me ask a few question here first...........
    when we talk about an AC and bulb power what do we mean the actual power or the apparent power?
    i mean the ratings are they based on o/p produce or i/p current?:confused:

    again are the bulbs in parallel as well:cool:...of course normally they all would be in parallel wont they?