cupoftea
Advanced Member level 5
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Hi,
In this video, at 1:30...
....it shows a device which has no batteries, but which gets all its operating power from the mains. It does this with a simple CT which clips round the mains line which enters the house. The same CT measures the mains current which leaves/enters the house.
What would you say is the best type of material for this CT? Surely it would best be iron? However, powdered-iron would be used as it would be cheaper to make “split ring”?
Also, I would have thought the having the current measurement function, and energy harvesting function, coming from the same CT, was somewhat of a compromise?
Would you agree it would be better if there were two secondaries, one for current measurement, and one for the harvesting? The harvesting one would pretty much be a full wave diode bridge into a big-gish capacitor? …and with a wee SMPS to give a known voltage output, and a clamping Zener in there for those occasions when the capacitor might otherwise get overvoltaged?
None of the web docs say much of the powdered iron material used....
In this video, at 1:30...
What would you say is the best type of material for this CT? Surely it would best be iron? However, powdered-iron would be used as it would be cheaper to make “split ring”?
Also, I would have thought the having the current measurement function, and energy harvesting function, coming from the same CT, was somewhat of a compromise?
Would you agree it would be better if there were two secondaries, one for current measurement, and one for the harvesting? The harvesting one would pretty much be a full wave diode bridge into a big-gish capacitor? …and with a wee SMPS to give a known voltage output, and a clamping Zener in there for those occasions when the capacitor might otherwise get overvoltaged?
None of the web docs say much of the powdered iron material used....
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