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I have 6 inverters that read non-invasive AC current clamp sensors.

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Each inverter reads a different current clamp, all clamped around the same 230 V wire. While this works, it is quite messy.

It was easy enough to find examples on the internet for reading current clamps and I have set up an ATMEGA328P to read one of the current sensors and transmit the reading via serial 200 yards to another ATMEGA328P, where I would like to replicate the output of the signal 6 times out of 6 to 3.5 mm jack sockets that I can plug each inverter into, so it will think it is reading its own current sensor.

Where I am now stuck is a simple way to output the replicated result that the inverter will see as a current clamp.

I believe each clamp outputs a current in proportion to the current flow through the wire.

How would I go about outputting a variable current source from an ATMEGA328P, or more specifically 6 identical variable current sources?

There are lots of examples on the internet for reading these clamps, but I am yet to find anything relating to pretending to be a current clamp.

The clamps in question are SCT-013-000 and the datasheet claims they output in the range of 0-50 mA.

Datasheet SCT-013-000

As reading these clamps is offset by 2.5 V, would I be correct in saying that the output current source may need to output a negative current also and therefore also need to incorporate some kind of H-Bridge?

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  • \$\begingroup\$ I think an h bridge is overkill, you can probably use an op amp, though you probably need to measure the load impedance of the inverters clamp input. \$\endgroup\$
    – Bryan
    Sep 19, 2022 at 23:15
  • \$\begingroup\$ It is my strong opinion the inverter is synchronously sampling the current transformer to determine the quality and safety of its output, your solution will have to be faster than it’s internal sampling so as to be transparent to it. \$\endgroup\$
    – Bryan
    Sep 19, 2022 at 23:28
  • \$\begingroup\$ i may be (probably am) wrong but i would have expected the inverter to sample its live input/output wires rather than the clamp as the inverter will function without the clamp connected when its output current is fixed set in the settings menu. \$\endgroup\$
    – Jay Dee
    Sep 19, 2022 at 23:32
  • \$\begingroup\$ basically i aim to set the output current from a micro controller rather than from the setting menu of the machine \$\endgroup\$
    – Jay Dee
    Sep 19, 2022 at 23:33
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    \$\begingroup\$ I have decided against messing about with these inverters live as they are running 3 houses with tenants and they wont be happy with me if there power goes down, so i have ordered another inverter to use on the test bench and will return to this soon, many thank \$\endgroup\$
    – Jay Dee
    Sep 22, 2022 at 7:08

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