0
\$\begingroup\$

I did build a single Phase voltage measurement controller and works.

The basic measurement methode is as this. The Diode 1N4007 is used to eliminate the negative half cycles. Using a voltage divider to lower the voltage to a RP2040 nice value. If I am right the impedance is ~1M ohm (mega-ohm) to avoid to execute a differential protection switch

Now I want to build a 3Phase voltage measurement controller, and its main purpose to check for the availability of all the three phases. If not; then a relais will cut off the main power of that 3Phase line ( kabel ).

The 3Phases should be checked against each other. So no N(Neutral should be involved. Otherwise I could use the schematic above.

I want to use a RP2040 in a closed box. No issues with that. The only thing is safety when measuring and power feeding the electronics.

I have not any idea or schematic that I should use to check the voltage between two Phases? Also how can I add all the fases together to get a 5vdc to power the electronics? If I add 6 more diodes then I got 400V... See lower part image.

I am almost sure ( hope I'am wrong ) that this isn't working. The good, the bad and the ugly???

\$\endgroup\$
7
  • \$\begingroup\$ You've done the simple bit, so now, show how you would connect a device that measures the voltage. Show power connections to that measurement circuit too and explain where they are derived from. I'm not talking about the three phase circuit, just the single phase circuit. Maybe you should simulate it to see the difficulty that you might find. \$\endgroup\$
    – Andy aka
    Commented Mar 14, 2023 at 14:55
  • \$\begingroup\$ It is just about the input that I have issues with, not the the connection to the ADC. I dont ask a question about the single phase but about the three phases. You talk about 'the simple bit', but thats the issue for me; for me its the hard bit. \$\endgroup\$
    – iPadawan
    Commented Mar 14, 2023 at 15:02
  • \$\begingroup\$ It may seem like the simple bit to you but, it's the hard bit and, may make you change your mind about how you do what you call the hard bit. \$\endgroup\$
    – Andy aka
    Commented Mar 14, 2023 at 15:21
  • \$\begingroup\$ Please keep your focus at the question. With your first comment I am right with my design? \$\endgroup\$
    – iPadawan
    Commented Mar 14, 2023 at 17:50
  • \$\begingroup\$ The trouble is that your question cannot be answered if you don't consider what I am talking about. At some point you should listen to what I'm saying. \$\endgroup\$
    – Andy aka
    Commented Mar 14, 2023 at 18:22

0

Reset to default

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.