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**Electronic circuits / Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"**

« **on:**December 02, 2019, 04:10:14 AM »

Some interesting recent comments, but still don't have a good handle on best frequency for melting copper in a graphite crucible.

It certainly isn't all that simple, is it?

I have found a few "Induction Heating Calculators" around on the internet. I think they probably do a fairly good job of estimating a few variables when it comes to iron and lower alloys of steel, but they seem to miss the target when getting into non-ferrous metals.

For instance, here's one of the "calculators":

https://www.plustherm.com/power-calculation.html

It took me some time to figure out how it works. (Note that you put in the whole number for the "Inductor Efficiency", not the percent as a decimal. That is- if your material is Aluminum, enter "40" not "0.40").

In the "Results" area, I am very dissapointed that it usually outputs an extremely low frequency in the "Minimum required frequncy" box. Why doesn't it know what frequency it actually used for that particular calculation?

And--- I am pretty certain that the results from their "minimum" frequecny and the ideal frequency would produce differing readings.

At first, I left the "Working Frequency" blank, so the calculator could choose, but even when I did enter a number, it didn't seem to help much.

After fooling around with the thing for a while, I realized that we aren't actually melting copper anyway with these 1800 watt to 2500 watt ZVS induction heaters, we are heating a graphite crucible! Well, there's no graphite in the Material choices box, so now what? I made a few guesses in the Inductor Efficiency box, estimating the graphite to be somewhere between "60" and "85", but no conclusive results.

It seems that some of the parameters in the "Details" area not closely related to the input parameters at all.

What do you guys think?

Pete Stanaitis

---------------

It certainly isn't all that simple, is it?

I have found a few "Induction Heating Calculators" around on the internet. I think they probably do a fairly good job of estimating a few variables when it comes to iron and lower alloys of steel, but they seem to miss the target when getting into non-ferrous metals.

For instance, here's one of the "calculators":

https://www.plustherm.com/power-calculation.html

It took me some time to figure out how it works. (Note that you put in the whole number for the "Inductor Efficiency", not the percent as a decimal. That is- if your material is Aluminum, enter "40" not "0.40").

In the "Results" area, I am very dissapointed that it usually outputs an extremely low frequency in the "Minimum required frequncy" box. Why doesn't it know what frequency it actually used for that particular calculation?

And--- I am pretty certain that the results from their "minimum" frequecny and the ideal frequency would produce differing readings.

At first, I left the "Working Frequency" blank, so the calculator could choose, but even when I did enter a number, it didn't seem to help much.

After fooling around with the thing for a while, I realized that we aren't actually melting copper anyway with these 1800 watt to 2500 watt ZVS induction heaters, we are heating a graphite crucible! Well, there's no graphite in the Material choices box, so now what? I made a few guesses in the Inductor Efficiency box, estimating the graphite to be somewhere between "60" and "85", but no conclusive results.

It seems that some of the parameters in the "Details" area not closely related to the input parameters at all.

What do you guys think?

Pete Stanaitis

---------------