Node-RED - Voorbeeld - Data via MQTT visualiseren

Op deze pagina vind je een voorbeeld met Node-RED hoe je data dat binnenkomt met MQTT koppelt aan een meter/grafiek.

Wat heb je nodig?

MQTT (client)
Python MQTT client (paho)
Node-RED Dashboard

Stap 1

Ik heb op mijn P1 poort een Raspberry Pi aangesloten en daarop een python script lopen dat zodra een telegram binnenkomt, deze ontrafeld wordt en het vermogen (W) via MQTT wordt doorgegeven naar de broker (waar ook Node-RED op draait).

Configureer:

Server
Publish naam

#!/usr/bin/env python
# Python script om P1 telegram weer te geven

import re
import serial
import paho.mqtt.client as paho

broker="raspberrypi.local"
port=1883

def on_publish(client,userdata,result): #create function for callback
  print("data published \n")
  pass

client1=paho.Client("control1") #create client object
client1.on_publish = on_publish #assign function to callback
client1.connect(broker,port) #establish connection

# Seriele poort confguratie
ser = serial.Serial()

# DSMR 2.2 > 9600 7E1:
ser.baudrate = 9600
ser.bytesize = serial.SEVENBITS
ser.parity = serial.PARITY_EVEN
ser.stopbits = serial.STOPBITS_ONE

# DSMR 4.0/4.2 > 115200 8N1:
#ser.baudrate = 115200
#ser.bytesize = serial.EIGHTBITS
#ser.parity = serial.PARITY_NONE
#ser.stopbits = serial.STOPBITS_ONE

ser.xonxoff = 0
ser.rtscts = 0
ser.timeout = 12
ser.port = "/dev/ttyUSB0"
ser.close()

while True:
  ser.open()
  checksum_found = False

  while not checksum_found:
    telegram_line = ser.readline() # Lees een seriele lijn in.
    telegram_line = telegram_line.decode('ascii').strip() # Strip spaties en blanke regels

    #print (telegram_line) #debug

    if re.match(b'(?=1-0:1.7.0)', telegram_line): #1-0:1.7.0 = Actueel verbruik in kW
      # 1-0:1.7.0(0000.54*kW)

      kw = telegram_line[10:-4] # Knip het kW gedeelte eruit (0000.54)
      watt = float(kw) * 1000 # vermengvuldig met 1000 voor conversie naar Watt (540.0)
      watt = int(watt) # rond float af naar heel getal (540)
      print watt

    # Check wanneer het uitroepteken ontavangen wordt (einde telegram)
    if re.match(b'(?=!)', telegram_line):
      checksum_found = True

  ser.close()

  ret = client1.publish("verbruik",watt) #publish

#!/usr/bin/env python

# Python script om P1 telegram weer te geven

import re

import serial

import paho.mqtt.client as paho

broker="raspberrypi.local"

port=1883

def on_publish(client,userdata,result): #create function for callback

print("data published \n")

pass

client1=paho.Client("control1") #create client object

client1.on_publish = on_publish #assign function to callback

client1.connect(broker,port) #establish connection

# Seriele poort confguratie

ser = serial.Serial()

# DSMR 2.2 > 9600 7E1:

ser.baudrate = 9600

ser.bytesize = serial.SEVENBITS

ser.parity = serial.PARITY_EVEN

ser.stopbits = serial.STOPBITS_ONE

# DSMR 4.0/4.2 > 115200 8N1:

#ser.baudrate = 115200

#ser.bytesize = serial.EIGHTBITS

#ser.parity = serial.PARITY_NONE

#ser.stopbits = serial.STOPBITS_ONE

ser.xonxoff = 0

ser.rtscts = 0

ser.timeout = 12

ser.port = "/dev/ttyUSB0"

ser.close()

while True:

ser.open()

checksum_found = False

while not checksum_found:

telegram_line = ser.readline() # Lees een seriele lijn in.

telegram_line = telegram_line.decode('ascii').strip() # Strip spaties en blanke regels

#print (telegram_line) #debug

if re.match(b'(?=1-0:1.7.0)', telegram_line): #1-0:1.7.0 = Actueel verbruik in kW

# 1-0:1.7.0(0000.54*kW)

kw = telegram_line[10:-4] # Knip het kW gedeelte eruit (0000.54)

watt = float(kw) * 1000 # vermengvuldig met 1000 voor conversie naar Watt (540.0)

watt = int(watt) # rond float af naar heel getal (540)

print watt

# Check wanneer het uitroepteken ontavangen wordt (einde telegram)

if re.match(b'(?=!)', telegram_line):

checksum_found = True

ser.close()

ret = client1.publish("verbruik",watt) #publish

Stap 2

Voeg in Node-RED een MQTT ingang (subscribe) toe, en “abonneer” je op het topic “verbruik”, configureer de MQTT server als localhost (potloodje)

Stap 3

Koppel aan de uitgang van de MQTT topic een meter:

Stap 4

Koppel aan de uitgang van de MQTT topic een grafiek:

Op het dashboard kan je dan je actueel verbruik zien:

Project in Node-RED clipboard:

[{"id":"af3b914f.da09c","type":"mqtt in","z":"8816a623.365d38","name":"verbruik","topic":"verbruik","qos":"2","broker":"3719830a.30f96c","x":890,"y":240,"wires":[["c96eb704.eff048","501fac51.dabe44"]]},{"id":"c96eb704.eff048","type":"ui_gauge","z":"8816a623.365d38","name":"Vermogen","group":"ecd6bf51.31fa5","order":0,"width":0,"height":0,"gtype":"gage","title":"VermogenMeter","label":"W","format":"{{value}}","min":0,"max":"4000","colors":["#00b500","#e6e600","#ca3838"],"seg1":"1500","seg2":"2500","x":1050,"y":220,"wires":[]},{"id":"501fac51.dabe44","type":"ui_chart","z":"8816a623.365d38","name":"VermogenTabel","group":"ecd6bf51.31fa5","order":0,"width":0,"height":0,"label":"","chartType":"line","legend":"false","xformat":"HH:mm:ss","interpolate":"linear","nodata":"","dot":false,"ymin":"0","ymax":"4000","removeOlder":"4","removeOlderPoints":"","removeOlderUnit":"3600","cutout":0,"useOneColor":false,"colors":["#1f77b4","#aec7e8","#ff7f0e","#2ca02c","#98df8a","#d62728","#ff9896","#9467bd","#c5b0d5"],"useOldStyle":false,"x":1060,"y":260,"wires":[[],[]]},{"id":"3719830a.30f96c","type":"mqtt-broker","z":"","name":"Local MQTT","broker":"localhost","port":"1883","clientid":"","usetls":false,"compatmode":true,"keepalive":"60","cleansession":true,"willTopic":"","willQos":"0","willPayload":"","birthTopic":"","birthQos":"0","birthPayload":""},{"id":"ecd6bf51.31fa5","type":"ui_group","z":"","name":"GWL","tab":"c1507dbd.860c1","order":1,"disp":true,"width":"6","collapse":false},{"id":"c1507dbd.860c1","type":"ui_tab","z":"","name":"Home","icon":"dashboard","order":1}]

[{"id":"af3b914f.da09c","type":"mqtt in","z":"8816a623.365d38","name":"verbruik","topic":"verbruik","qos":"2","broker":"3719830a.30f96c","x":890,"y":240,"wires":[["c96eb704.eff048","501fac51.dabe44"]]},{"id":"c96eb704.eff048","type":"ui_gauge","z":"8816a623.365d38","name":"Vermogen","group":"ecd6bf51.31fa5","order":0,"width":0,"height":0,"gtype":"gage","title":"VermogenMeter","label":"W","format":"{{value}}","min":0,"max":"4000","colors":["#00b500","#e6e600","#ca3838"],"seg1":"1500","seg2":"2500","x":1050,"y":220,"wires":[]},{"id":"501fac51.dabe44","type":"ui_chart","z":"8816a623.365d38","name":"VermogenTabel","group":"ecd6bf51.31fa5","order":0,"width":0,"height":0,"label":"","chartType":"line","legend":"false","xformat":"HH:mm:ss","interpolate":"linear","nodata":"","dot":false,"ymin":"0","ymax":"4000","removeOlder":"4","removeOlderPoints":"","removeOlderUnit":"3600","cutout":0,"useOneColor":false,"colors":["#1f77b4","#aec7e8","#ff7f0e","#2ca02c","#98df8a","#d62728","#ff9896","#9467bd","#c5b0d5"],"useOldStyle":false,"x":1060,"y":260,"wires":[[],[]]},{"id":"3719830a.30f96c","type":"mqtt-broker","z":"","name":"Local MQTT","broker":"localhost","port":"1883","clientid":"","usetls":false,"compatmode":true,"keepalive":"60","cleansession":true,"willTopic":"","willQos":"0","willPayload":"","birthTopic":"","birthQos":"0","birthPayload":""},{"id":"ecd6bf51.31fa5","type":"ui_group","z":"","name":"GWL","tab":"c1507dbd.860c1","order":1,"disp":true,"width":"6","collapse":false},{"id":"c1507dbd.860c1","type":"ui_tab","z":"","name":"Home","icon":"dashboard","order":1}]

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Node-RED – Voorbeeld – Data via MQTT visualiseren