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mruettgers / SMLReader

ESP8266 based smart meter (SML) to MQTT gateway
GNU General Public License v3.0
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Reading two SmartMeters with one ESP #40

Closed TE-2 closed 2 years ago

TE-2 commented 2 years ago

Hello, first of all i like your project very much and thanks for sharing it !

Now my question: I have two smartmeters and would like to read them simultaneously via two BPW40 transistors with one ESP. Is this possible and if so what changes in the code do I have to make and how do I connect the second transitor to the ESP ?

mruettgers commented 2 years ago

Hey @T2FF,

multiple reading heads should work without problems. You just have to configure the heads as described here: https://github.com/mruettgers/SMLReader#configuration

syssi commented 2 years ago

I'm reading 3 smartmeters with one ESP without issues.

TE-2 commented 2 years ago

okay thank you very much for the quick feedback.

Is this correct? SML

Because I do not quite understand the circuit. According to my understanding, if the 3.3V pin is an "ideal" voltage source, the same potential should always be present at the digital inputs. The only thing that changes in my opinion is the current flow, because the transistors are connected in parallel, but digital inputs can not measure current flow?

benniju commented 2 years ago

In the image the two inputs are basically put in parallel, so they will always turn on and off together. Because of this, that can not work. You need two separate resistors for each sensor.

TE-2 commented 2 years ago

So you mean something like this ? SML

Update: this wiring diagram works for me! nevertheless I still do not know how this circuit works