I think I get confused between the heater Power rating and the energy consuming,
Can I put 800 joule per second as specefic heater value in the circuit ? or it must be just 800 Watts ?

Common ratings of heaters are in watts and operating voltage, so giving a rating in joules per second will only be useful for somebody doing an energy use analysis. The information will not help in servicing or determining power consumption.

 

Common ratings of heaters are in watts and operating voltage, so giving a rating in joules per second will only be useful for somebody doing an energy use analysis. The information will not help in servicing or determining power consumption.

Agreed.
In this phase, i'm not about energy analysis issue, i'm just aspire to make perfectly AC circuit analysis, so i have to define the heating element and calculate the ecaxt resistance value before calculate the circuit.

 

Agreed.
In this phase, i'm not about energy analysis issue, i'm just aspire to make perfectly AC circuit analysis, so i have to define the heating element and calculate the ecaxt resistance value before calculate the circuit.

The resistance of heating elements generally increases as they heat. And the wattages given are mostly nominal. The watt rating is adequately close for calculation of the wiring to connect the appliance but that may not be close enough for your purpose.

 

Since your heating element runs on AC, the sine waves will cause the heating element to change resistance during each positive and negative cycles. There will mostly likely be some reactance as well.

Its perfectly fine to use RMS to calculate your power and move forward, you are just repairing this thing and not redesigning it, correct?

 

The resistance of heating elements generally increases as they heat. And the wattages given are mostly nominal. The watt rating is adequately close for calculation of the wiring to connect the appliance but that may not be close enough for your purpose.

So we are talking about the Thermal resistance in this case.
Surely in the Steady state : Rth = Voltage squared / Power = (230*230) / 800 = 66.125 ohms.
In the Unstedy state it will be Temperature function, but i dont understand how should be section wires function ?
Here the graph of the thermal resistance, it's not values exact, untill I can write the Temperature of the heating element versus time equation.

 

Since your heating element runs on AC, the sine waves will cause the heating element to change resistance during each positive and negative cycles. There will mostly likely be some reactance as well.

Its perfectly fine to use RMS to calculate your power and move forward, you are just repairing this thing and not redesigning it, correct?

Yes correct, i'm just repairing it, because as you know I will just re-use the same elemnts, and repairing without understanding is not so helpful I think.
So,i will try to understand the RMS, just i want know, in this Ac circuit, whe have just One sine wave or many waves ? I want just an idea if possibel.

 

RMS is simple, it's root mean square which is your average voltage of the sine wave. There is only one sine wave which we will consider in this case. It is 60 Hz in US, 50 Hz in EU and other countries.

https://en.wikipedia.org/wiki/Root_mean_square


We usually measure our line voltage in RMS, so your 110 or 240 would be the RMS value. Using the equation you get average power. It's simple no need to complicate it.

 

RMS is simple, it's root mean square which is your average voltage of the sine wave. There is only one sine wave which we will consider in this case. It is 60 Hz in US, 50 Hz in EU and other countries.

https://en.wikipedia.org/wiki/Root_mean_square

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We usually measure our line voltage in RMS, so your 110 or 240 would be the RMS value. Using the equation you get average power. It's simple no need to complicate it.

Just I thgout that RMS is an AC circuit analysis software.