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Matching Of Source AC power To Isolation Transformer Primary?

russwr

Dec 20, 2019
15
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Dec 20, 2019
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If winding the primary of isolation transformer, which value should be used-- ohms as from volts divided by current, or impedance of AC source as terminals resistance, with the high frequency KHZ that runs the primary?? The online calculator asks for reactance in ohms of inductor to get the inductance value. Then the number of turns is calculated for primary by the on line calculator for toroid core that uses the inductance. Impedence is the square, of ratio of volts, since the number of turns is not known to begin with.
 

Martaine2005

May 12, 2015
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May 12, 2015
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4,306
Have a read of this Digikey article.
It might have the information you require. An isolation transformer has identical primary and secondary windings to give 1:1 ratio. A transformer will still have isolation between primary and secondary windings but the voltages will either be higher or lower (step up, step down). However, be careful grounding (earth) the secondary as isolation will be circumvented.


Martin
 

russwr

Dec 20, 2019
15
Joined
Dec 20, 2019
Messages
15
If winding the primary of isolation transformer, which value should be used-- ohms as from volts divided by current, or impedance of AC source as terminals resistance, with the high frequency KHZ that runs the primary?? The online calculator asks for reactance in ohms of inductor to get the inductance value. Then the number of turns is calculated for primary by the on line calculator for toroid core that uses the inductance. Impedence is the square, of ratio of volts, since the number of turns is not known to begin with.
 

russwr

Dec 20, 2019
15
Joined
Dec 20, 2019
Messages
15
The other option is to remove the reactance 2 ohms that the primary coil has against the incoming AC frequency power. A matching capacitor could be put in "SERIES" so that there is resonance of L and C that matches the input 20khz frequency power. That way maybe more power will get through to the secondary side of step up isolation transformer, instead of loss of 8 volts. I had previously used only "PARALLEL" capacitor. What do you think? (Best quality is non polarized polypropylene only AC capacitor)
 
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