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ruchita said:
hi ,
i m a electrical engineering student 1st year
and i would like to know when it is appropriate time to join training in industries?
please suggst me
May be in your 3rd Year of the 4 year degree course. In fact we are conducting an introductory training programme to engineering students at our training centres in Pune, Lucknow & Coonoor. Let me know if you are interested.
jatin333 said:
what is % impedance of transformer? how we calculate %impedence of transformer,
what is purpose of % impedence?
Have you ever wondered why the name plate LV Volatge in a transformer is 433V but the name plate voltage of an LV motor is 415V? Are they both not LV? Yes! the 433 V in a trf. name plate is the open circuit voltage or the no load voltage. But, when you load the transformer, a current would flow thro its windings. As the windings will have an impedance, this current and impedance would very definitely cause a voltage drop within the transformer windings. On emust know the magnitude of this voltage drop. The volatge drop within the transformer's LV windings, with rated load current flowing thro it, expressed as a percentage of the no load voltage of the teansformer is called its percentage impedance.
visweswar rao said:
HAI IAM VISSU,
IAM WORKING AS AN ELECTRICAL ENGINEER IN SPINNING MILL.
RECENTLY APSPDCL POWER BILLING ON KVAH INSTEAD OF KWH.
SO WE HAVE TO MAINTAIN PF 0.99 TO UNITY OR LEADING PF.
IF WE MAINTAIN LEADING POWER FACTOR , ANY DISADVANTAGES ARE THERE?
PLS LET ME KNOW.
Yes! There are definite problems. Your EB or DISCOM calculates the monthly average power factor by the formula PF = kWh/kVAh. Please note that you do not gain any big advantage even with leading power factor. Because even with leading power factor the kVAh is going to be more and kWh less. SO, you will still have poor power factor and will be penalised. There could be other probelms such as voltage boost, etc. with leading PF
Ali said:
what is the approperiate setting for O/L shall it be 115% of the FLA or of the actual current of the motor or the same as FLA of the motor
some one says 115% of FLA and others says 100% FLA and other says 125%FLA
i heared many things so i'm confusing
Not more than the rated full load current of the motor.
Anil Gadher said:
We are facing a problem in 33kv HT panel, there are continuous traking on CT. what is the reason and what is the remedy.
Pollution is the problem.
karam_2010 said:
heloo,every body.
i want to know how can i calculate unbalance by current?
By a method called Symmetrical Components
Nawaz said:
This can be viewed from other term too. As we know the average power consumed by a inductor or a capacitor over a complete cycle is zero.During the first half cycle a field builds up across the inductor and during the second half cycle the field collapses. So power has to be returned back to source
A bit of correction! It is not between the two half cycles. Even in the same half cycle, the charge builds up from zero to maximum in the first half of the half cycle and then from the peak to zero of the same half cycle, the built-up charge would discharge back to the source. Again, in the next half cycle, the same process is repeated albeit in the reverse polarity.
30mA ELCB is good enough. But, just in case you want to improvise, you may go for 10mA ELCBs at least for devices in wet areas.
Salvia Divinorum said:
Energy efficiency is important, but efficiency won’t solve our growing energy needs. Nuclear power plants will.
I am sorry! You are wrong! “Energy Efficiency” will surely solve our problems. Keeping on adding generation capacity, without pating attention to energy savings is like filling a “leaking bucket”.
