How do I calculate PFC?

How do I calculate PFC?

You’d do I = V/R, which is the same as PFC = V/Ze. I know R is resistance and Z is impedence, but that is the formlae and it’s the calculation a tester makes when taking a PFC reading.

What is the formula of for 3 phase power factor?

​P = √3 × pf × I × V​ This simply states that the power is the square root of three (around 1.732) multiplied by the power factor (generally between 0.85 and 1, see Resources), the current and the voltage.

Why do we measure PFC?

A PFC test calculates the current that will flow in the event of an earth fault; i.e., Line to Earth. It is important that we conduct the tests to make sure that the protective devices installed within a circuit are rated at the correct breaking capacity.

What is a good Pfc reading?

There is no such thing as acceptable PFC. It is what it is. When testing on 3-phase supplies the simplest and quickest way is to take the highest PFC reading off the single phase and double the value. Use Ohms Law to check.

Where is the highest value of PFC?

the source of the
The PFC will continuously be the highest at the source of the installation as the impedance/resistance is always the lowest there. So as a regulation, if it’s not too extreme at the mains it will be fine everywhere else.

How is SC current calculated?

This applied voltage divided by the rated primary voltage (times 100) is the impedance of the transformer. Example: For a 480 Volt rated primary, if 9.6 volts causes secondary full load current to flow through the shorted secondary, the transformer impedance is 9.6/480 = . 02 = 2%Z. * Note 2.

What is the maximum PFC?

If your meter can measure 415v, just directly measure P to P. Most DNO’s will state their maximum PFC on their connection agreements. WPD declare 16ka for single phase and 25ka for three/split phase. Ring your local DNO to find out theirs.

Why do we test PFC?

What is fault level calculation?

Transformer short circuit fault current Calculations I(fault) = S(kVA) x 100 / (1.732 x V(V) x %Z). The %Z will lie between 4 to 10%. Example: A transformer’s nameplate details are 25 kVA, 440V secondary voltage, 5% of percentage impedance, calculate the short circuit fault current.

What is 3 phase short circuit current?

The 3-phase short-circuit fault level PSC, in kA or in MVA is given by the power supply authority concerned, from which an equivalent impedance can be deduced. The upstream (MV) resistance Ra is generally found to be negligible compared with the corresponding Xa, the latter then being taken as the ohmic value for Za.