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How to power CT without plugging the lead into EmonTx?

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I have arduino uno and CT. I want to use my CT to measure current but i do not have EmonTx. Where do i plug my CT leads into? Or how do i power it without EmonTx? What power does it take or what is the functionality of those leads?

The CT is a totally passive device. It draws the minute amount of power it needs from the circuit that you are measuring. You cannot connect your CT directly to the Arduino, you must make a small circuit that sits in between. Read the page in Resources > Building blocks about interfacing a CT to an Arduino.
Also there, you can read exactly how everything works and there is a link to the sketch you need to run to measure the current.

Thank for your support. I have found the small circuit needed here.
https://openenergymonitor.org/emon/buildingblocks/how-to-build-an-arduino-energy-monitor-measuring-current-only
But in this CT has 2 output terminals coming out of it where as the one i have, has only one lead coming out of it!
How do i get 2 terminals instead of that lead?

The 3.5mm jack-plug at the end of the CT’s lead has 3 contacts; these are known as tip, ring and sleeve. Only two of these contacts are used, the being the tip and the sleeve. By inserting the plug into a compatible socket, the signals at these two contacts can be accessed.

https://openenergymonitor.org/emon/buildingblocks/report-yhdc-sct-013-000-current-transformer

As mentioned earlier, the signal needs to be processed by the standard circuitry so that measurements of AC current can be made by the processor.

There’s more about the CT connections in this thread:
https://openenergymonitor.org/emon/node/2960

Thank you so much !
:slight_smile: