Parse input mqtt from nodemcu

[Suslik]

Hello Together,
I am new in using node-red and need your help.
I have this one as input as mqqt in node-red and i am interesting in getting an output value just for the Power_curr value.´

The change node does not work when copying the value Power_curr it is "payload[""].Power_curr" and the node change marks it as red...

Has someone any ides?

Thanks

[cymplecy]

hover over the copy path and click on it to see what that give you

[Sean-McG]

Your payload looks a bit odd for tasmota, what sensor is this for ?

Normally there is the sensor type object containing the data eg

[bakman2]

@Sean-McG

Your payload looks a bit odd for tasmota, what sensor is this for ?

Yes I was also was reading it like it is missing a property name, this is strange, never seen this before (how is it even possible ?)

[Colin]

Out of interest, what do you see if you tell the mqtt node to return a string? Also what if it returns a buffer? I wonder if there is an unprintable character as the key name.

[Suslik]

hi i used it and it gave me this here
payload[""].Power_curr"

[Suslik]

it a sensor for smart meter to read out and show the current power electricity usage of the house

[Suslik]

this how it looks inside the console

[cymplecy]

Try setting your MQTT node to keep it as a string and then do a replace "" to something like "xx" in a change node then feed onto the JSON node and you should be able to get a sensible reference to it

payload.xx.Power_curr

[dynamicdave]

I'm using Tasmota 12.3.1 (yours says 12.3.1.3) on a Wemos D1 Mini connected to a PZEM-004T to send readings to Node-RED via MQTT.

I have a MQTT-In node configured like this..

Which gives object-data like this in a debug node...

Note: I have a section named ENERGY, which seems to be missing in your object.

Using my Node-RED flow, I just pull-out the data I need and display on my dashboard.

[Sean-McG]

You can see the object name is "" in that shot, not sure why, did you change any settings relating to topics structure on tasmota setup ?

May be worth asking on tasmota discord

[bakman2]

Does the sensor actually have a name in the tasmota config, what kind of module is it and/or are you using a template ?

[Suslik]

Thanks to all your support

not really.
I habe used now a different smart meter code and i have now this one.

now i have main instead ""

using a change node

but still i do not get a single value

i get this one.

i changed also the version to 12.3.1

i need just the single value for power

[cymplecy]

Can you please try my idea and see if it works for you - it works for me

[Suslik]

it worked now. Thanks to everyone.
I needed to delete the debug node and recreate it. Something was there wrong.

Thanks