Variable Frequency Control is a system for controlling the rotational speed of an AC electric motor by controlling the frequency. You need system for controlling the power of a heating element.Jack the dripper wrote:New to this site. Real new like 5 minutes ago. maybe this isn't the place for this question............ Why wouldn't it be possible to control a heating element with a Variable Frequency Control?

Heating element is a resistive circuit. Power of a resistive circuit depends on the potential difference and resistance of heating element and does not depend on frequency. The change of frequency will not change power of heating.

How to change a power?

In resistive circuits , electrical power is calculated using Joule's law:

P = V x I, where

P is the electric power,

V the potential difference,

and I the electric current.

We can combine Joule's law with Ohm's law (V = RхI) to produce alternative expressions for the dissipated power:

P = V^2/R,

where R = constant - it is the electrical resistance of our heating element.

The change of potential difference will change power of heating.

Otherwise, P = I^2 x R

The change of current will change power of heating.

But the change of frequency will not change power of heating.