negesti
commented
3 months ago i had to add a delay to the registers. Wattsonic uses baudrate 9600 and I had serial timeouts reading the registers at once (always the last register that is read fails with a timeout).
After checking the sourcecode, i notices that modbus supports a delay property (not listed in the docs). My current config is:
#############################################################################
#
# Meters - read from Wattsonic using Modbus RTu connected by /dev/ttyACM0
#
# https://docs.evcc.io/docs/reference/modbus#manuelle-konfiguration
#
# All register share the same modbus bus configuration
# source: modbus
# id: 247
# device: /dev/ttyACM0
# baudrate: 9600
# comset: "8N1"
# rtu: true
# timeout: 10s
# delay: 1s # dont read all registers at once
# scale: 1.0 # some registers require a scale, double value using ., negative values are supported
# register:
# type: holding # coil, input, holding
# address: >id< # check documentation of you inverter
# decode: >type< # check documentation of you inverter [u]int16|32|64 , float32|64,
#
#
#############################################################################
meters:
- name: meter-grid
type: custom
power: # power (W)
source: modbus
id: 247
device: /dev/ttyACM0
baudrate: 9600
comset: "8N1"
rtu: true
timeout: 10s
scale: -1.0
delay: 3s
register:
address: 11000 # Total Power on Meter
type: holding
decode: int32
- name: meter-pv
type: custom
power: # power (W)
source: modbus
id: 247
device: /dev/ttyACM0
baudrate: 9600
comset: "8N1"
rtu: true
timeout: 10s
delay: 2s
register:
address: 11028 # PV Input Total Power
type: holding
decode: int32
- name: meter-battery
type: custom
power: # power (W)
source: modbus
id: 247
device: /dev/ttyACM0
baudrate: 9600
comset: "8N1"
rtu: true
timeout: 10s
delay: 1s
register:
address: 40258 # Total_Backup_P
type: holding
decode: int32
soc:
source: modbus
id: 247
device: /dev/ttyACM0
baudrate: 9600
comset: "8N1"
rtu: true
scale: 0.01
timeout: 10s
delay: 1s
register:
address: 43000 # SOC
type: holding
decode: int16
Finally i got a configuration for the Wattsonic Gen 2 inverter that reads pv/grid/battery power and the battery SOC
The same inverter (at least Gen3) is distributed as Sunway, Solinteng, A-Tronix and St-ems)
Thanks to @andig for his patients with my misunderstanding of reading negative values from modbus.
Originally posted by @negesti in https://github.com/evcc-io/evcc/discussions/14477#discussioncomment-10027717