Role of inductor in AC phase control

Thread Starter

Alchemy One

Joined Oct 5, 2019
217
I am sitting and looking at this phase control circuit to control AC motor speed.
Looking at the inductor in the circuit and wondering what is its purpose.
I speculate that it is perhaps to slow down inrush current since that is what inductor seem to exhibit as it begins to charge, the opposite of a capacitor which at first acts like a short circuit.

If it is for some other purpose is one thing but if it is not, I sit and wonder if this device can even handle any current that a motor draws. Just what kind of resistance this 220uh has, that is what is its wattage or current handling capability that a load can draw.

I don't see that it can handle anymore than a simple fan motor before it is toast.
If I am correct then what values would be needed including all them capacitors.
It appears to me that the triac can handle far more than all the capacitors, the diac and especially the inductor.
What kind of current can one draw from this circuit assuming changing the other components values. If so, what values?
It is obvious where the inductor is placed. It is in the path of main current so is that first capacitor with no voltage value on it.

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ronsimpson

Joined Oct 7, 2019
3,037
We can not make a comment on the inductor until I see it. I have a 220uH 100A inductor in my bench.
It looks like there is more to the schematic.
 

Thread Starter

Alchemy One

Joined Oct 5, 2019
217
We can not make a comment on the inductor until I see it. I have a 220uH 100A inductor in my bench.
It looks like there is more to the schematic.
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That is what I thought. I figured something is not right. It is all I have from the EEWeb.
100A?
I didn't know how to get information on inductors online except about thier values in terms of henrys and shape and frequency.
Perhaps I should type amperage along with it.
Also I don't think this so called phase control is good with any induction type of motor. It should be okay with universal motors. I have changed the values of what is in the schematic. I want to ad a full bridge recitifier with it and as far as the inductor goes... I suppose I just use a good robust choke and call it good.
What do you think?
I am using just two capacitor in the circuit, one with 400V and .1uF from the diac. And across the power rails I am using 275V .1uF with a 100ohm 3 watt resistor top and bottom. 100K potentiometer and 4K 3 watt resistor with it.
( In a nutshell, you don't want to see my inductor unless you want a good laugh)
 
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