question

While I do not use home assistant, I use SmartThings for my IoT flavor of choice. But it should be pretty similar in functionality. Do you have API access and the ability to create device definitions in HA?

What I did is create a python script that reads the Victron modbus tcp registers every 5 minutes and send that data to an self defined device end points in SmartThings. I set the python scrip to fire via a cron job on the Rpi. Once the SmartThings devices receive the data, I can create all kinds of rules based on data thresholds. Like turn off certain outlets if SOC gets down to certain point. Or, flash some lights when SOC is 100%. etc, etc.

Anyway, google "victron python modbus tcp". That will get you going down the "rabbit hole" as they say.

BTW, here's some screenshots of the devices I created. One for my BMV-712 and one for my Morningstar MPPT 60 Solar Charge controller.

Solar

I think I'm with you on that one GroundAttack, @Todd Wackford, any chance you might be willing to post the script here.
G

@georgelza,

Here is the Python script. I have it run from a cron job every 5 minutes. I'm assuming you have SmartThings. You will need to change lines 131 and 133 to input your credentials and ID for SmartThings. Hope this helps you out.

#!/usr/bin/env python

#

from pymodbus.client.sync import ModbusTcpClient as ModbusClient
from pymodbus.constants import Endian
from pymodbus.payload import BinaryPayloadDecoder
from pymodbus.payload import BinaryPayloadBuilder
from pymodbus.client.sync import ModbusTcpClient as ModbusClient
from pymodbus.compat import iteritems
import time
import sys
import json
import httplib

def ConvertSectoDay(n):
    if n == 0:
        return "infinite"
    
    day = n // (24 * 3600)
    n = n % (24 * 3600)
    hour = n // 3600

    n %= 3600
    minutes = n // 60

    n %= 60
    seconds = n
    #need to  add if statement to send minutes when less then one day
    if day > 0:
        return(str(int(day)) + 'd ' + str(int(hour)) + 'h')
    else:
        return(str(int(hour)) + 'h ' + str(int(minutes)) + 'm')

        
####################           Main section of code           ####################
# configure the client logging
import logging
logging.basicConfig()
log = logging.getLogger('./modbus.error')
log.setLevel(logging.ERROR)


#Define variables for the connection
host = '192.168.10.92' #this is IP of the venus GX
port = 502
systemUnitId = 238   

#Make the connection to the Venus Device
client = ModbusClient(host,port)
client.connect()

# Define the output json object and initialize with some SmartThings needed information
jsonOut = { "event" : "batteryUpdate", "dni" : "bmv712", "data": {} }

#map out our scale values to use for the measurement types
v_scale =   100 #volts
i_scale =   10  #current
t_scale =   10  #temperature
ah_scale =  -10 #Amp hours
no_scale =  1   #No scaling
time2Go_scale = .01 #Time to go

# Setup up a data mapping object to use for processing and name/value pairs
from collections import namedtuple

# Read the registers and add to our records object
measurementType = namedtuple('measurementType', 'name address scale type')
records = []
records.append(measurementType(name='voltageMeasurement', address=259, scale=v_scale, type='uint'))
records.append(measurementType(name='current', address=261, scale=i_scale, type='int'))
records.append(measurementType(name='temperature', address=262, scale=t_scale, type='int'))
records.append(measurementType(name='consumedAmpHours', address=265, scale=ah_scale, type='uint'))
records.append(measurementType(name='battery', address=266, scale=i_scale, type='uint'))
records.append(measurementType(name='alarm', address=268, scale=no_scale, type='uint'))
records.append(measurementType(name='relayStatus', address=280, scale=no_scale, type='uint'))
records.append(measurementType(name='deepestDischarge', address=281, scale=ah_scale, type='uint'))
records.append(measurementType(name='lastDischarge', address=282, scale=ah_scale, type='uint'))
records.append(measurementType(name='averageDischarge', address=283, scale=ah_scale, type='uint'))
records.append(measurementType(name='chargeCycles', address=284, scale=no_scale, type='uint'))
records.append(measurementType(name='batteryTimeToGo', address=303, scale=time2Go_scale, type='uint'))

# Cycle thru records, scale the values and populate the json object
for record in records:
    result = client.read_holding_registers(record.address, count=1,  unit=systemUnitId)
    decoder = BinaryPayloadDecoder.fromRegisters(result.registers, Endian.Big)
    if record.type == 'uint':
        value = decoder.decode_16bit_uint()
    else:
        value = decoder.decode_16bit_int()
        
    jsonOut['data'][record.name] = float(value)/record.scale
    
#Now handle any additions or reformatting that we may need to do
#Battery Power
jsonOut['data']['power'] = round(jsonOut['data']['current']*jsonOut['data']['voltageMeasurement'], 1)

#Relay status
relayStates = ['Open', 'Closed']
jsonOut['data']['relayStatus'] = relayStates[int(jsonOut['data']['relayStatus'])]

#alarm status
alarmStates = ['OK', 'Alert']
if jsonOut['data']['alarm'] > 0.5:
    state = 1
else:
    state = 0
jsonOut['data']['alarm'] = alarmStates[state]

#Time to go
jsonOut['data']['batteryTimeToGo']  = ConvertSectoDay(jsonOut['data']['batteryTimeToGo'])

#we have all the data.
batteryJson = json.dumps(jsonOut)
client.close()

#show the json data on the console
print("---------------- JSON of Battery Data from Venus GX ----------------------")
print(batteryJson)
print("----------------              END OF JSON           ----------------------")


#Now open a connection to SmartThings and dump the data Venus (Connect) App.
conn = httplib.HTTPSConnection("graph.api.smartthings.com:443")
payload = batteryJson
headers = {
    'content-type': "application/json",
    'authorization': "Bearer #ST TOKEN HERE#"
    }
conn.request("POST", "/api/smartapps/installations/#installation ID here#/appHook", payload, headers)
r1 = conn.getresponse()
print r1.status, r1.reason

#TODO: Need to do some sort of error handling if SmartThings response has error.
conn.close()

Using modbus to get data into Home asistant is easy and simple way. Unfortunately has one restriction. Unlike MQTT it will work only if Venus and Home assistant are on the same local network.

I have instalation in camper, so if I left home wifi network, cerbo gx will get different ip from LTE modem and modbus connection will not work.

I would rather prefere if cerbo GX can transfer data to my MQTT server.