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There is a thief in the electrical system: Power Factor

I promise you will never forget this any more!

kW = voltage x current x pf

We say the better the power factor i.e. the closer to 1 the better…


Say 34.4kW= 400V x 100amp x 0.869(pf)

Say 40kW= 400V x 100amp x 1(pf) –

You get more kW with bad power factor…or do you?

But what power is this Volt x Current (V x I)?

It is THE TOTAL ELECTRICAL POWER CONSUMED by a load, aka the VA or kVA, in the system not considering power factor. Yes!

It is also by no accident that it is known as the “APPARENT POWER” (Why? We expected this to be the power used by our machinesĀ  – but it is not!! see: “Apparently”) get the pun?

And the light goes on…or does it?

If not, then one must by now at least realise – We supplied 40kW but we only used 34.4kW…something stole 5.6kW – well that something is BAD/LOW POWER FACTOR…it steals from you and you don’t even know it.

At PF = 0.86 you only have 34.4kw available to do your work and at PF = 1 you have a whole 40kW to do the same work.

This 34.4kW is called the REAL POWER. Believe it or not, it is also so called in the electrical formulas.

Hah, now the light is on, the same current was flowing but somehow a dark horse came and stole some of your power.

What’s upĀ  with our lost 5.6kW?

Take a wild guess what is this “lost power” called?

IMAGINARY POWER (I saw this in maths class) or also known as REACTIVE POWER (but this comes from another angle). It literally gets dissipated in the electrical components making them work harder for no apparent reason?

There done…the mathematics and all.

Oh before you go: How can we fix this problem?

The low down is: Inductance causes low (lagging) power factor and its nemeses is capacitance.

So how do we get rid of this electrical thief?

Add the correct amount of capacitors in the circuit and voila – mission accomplished.

There is much more to be said about this, but I think at this level we killed it.

If only we had a similar tool to fix criminality in the real world!

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