Let's Control It

bidrohini wrote: ↑07 Nov 2023, 13:17 Thanks for sharing. Could you please tell me what is the advantage of using a precision rectifier instead of CT? Does it make the coding easier?

Olfried wrote: ↑07 Nov 2023, 20:47 You're absolutely right!

This circuit only works "perfect" with a pure sinus, with no phase shifting.
But it produces good results if you calibrate it with the power consumer you know, what should be the normal behaviour.

You could use a truee RMS chip of course, but that is not what i wanted to achieve (and much too expensive for me!)

My friend has just a pump in his cellar and only wants to know if it is running or not.
He wants to use ESP Easy and i use the ADC input for voltage, so this might be the right solution.

BTW, i tried it with my drilling machine. That is far away from a sinus, but it worked good enough for me.

Greetings
Olaf

Olfried wrote: ↑07 Nov 2023, 21:52

Olfried wrote: ↑07 Nov 2023, 20:47 You're absolutely right!

This circuit only works "perfect" with a pure sinus, with no phase shifting.
But it produces good results if you calibrate it with the power consumer you know, what should be the normal behaviour.

You could use a truee RMS chip of course, but that is not what i wanted to achieve (and much too expensive for me!)

My friend has just a pump in his cellar and only wants to know if it is running or not.
He wants to use ESP Easy and i use the ADC input for voltage, so this might be the right solution.

BTW, i tried it with my drilling machine. That is far away from a sinus, but it worked good enough for me.

Greetings
Olaf

BTW, this is nearly, how my drilling machine looked like. A lot of noise, but this seems to be no problem because the rektifier measures just the peak voltage (which you have to interprete of course).

Click here:
https://www.falstad.com/circuit/circuit ... Pg3N4GHxQA

Olfried wrote: ↑07 Nov 2023, 20:47 My friend has just a pump in his cellar and only wants to know if it is running or not.

chromo23 wrote: ↑07 Nov 2023, 22:04

Olfried wrote: ↑07 Nov 2023, 20:47 My friend has just a pump in his cellar and only wants to know if it is running or not.

Hey Olaf,

for that purpose i flashed several Gosund SP1.
I wrote rules for them and used "easyfetch" as a dashboard.
They now monitor if a Pump is running and detect if the pump is running dry and turn off the pump if so.
Furthermore since the pumps we use have membrane container (i don´t know if this is the right term but you probably know what i mean) it also detects when the time between activations become shorter. This is a sign for checking the counter pressure.
All this works really well with the power of ESPeasy rules!

(this is a bit more pro but i also added a flow switch for detecting the running water. It is really sensitive. If the water runs for 30min the pump gets turned off)

I unfortunately have only a screenshot of the dashboard but not of the installation
Bildschirmfoto 2023-11-07 um 22.00.25.png

Olfried wrote: ↑07 Nov 2023, 22:18 The problem is, that my friend doesn't want to break up the electric wiring for his Pumps. They are wired directly to the electric cabinet and he doesn't want anything between the pumps and power source.
That's why i wanted to use CTs.

Olfried wrote: ↑07 Nov 2023, 20:50

bidrohini wrote: ↑07 Nov 2023, 13:17 Thanks for sharing. Could you please tell me what is the advantage of using a precision rectifier instead of CT? Does it make the coding easier?

Oh, sorry for the confusion.
I don't replace the CTs. It is just the electronics behind it.

The solutions which are out there also use CTs. But they just add an offset to the AC output of the CTs and measure the curve directly.

With my circuit the AC is rectified and produces a DC voltage which can be easely measured with ESP Easy. That's all!

Olaf