HA starting slowly when Modbus sensor not available

Configuration
1

Hi,
using
Raspberry Pi 4
HA 2024.1.3

I pull sensor data from my PV inverter every 2 seconds. Below is part of the code.

Problem:
Whenever the PV inverter is offline (every night when there is no sunlight), HA seams to start very slowly. Normally it restarts within less than a minute. Now it takes something like 5 Minutes and the dashboard also loads very slowly after HA has been started.

Desired Solution:
Modbus devices that are offline (sensor data not available) should ideally not slow down HA startup. Maybe I have missconfigured something? Or is it a bug?

Here is the code from configuration.yaml:

modbus:
      ### Wechselrichter 1 Kostal Piko CI 50
  - type: tcp
    host: 192.168.xx.xx
    port: 1502
    name: WR1_PikoCI50_Modbus
    sensors:

    - name: WR1_DC_Total_power
      slave: 71
      #scale: 0.1
      precision: 2
      address: 100
      scan_interval: 2 # Defines the update interval of the sensor in seconds.
      #count: 2 # Anzahl zu lesenden Register
      data_type: float32
      #swap: word
      device_class: power
      state_class: measurement
      unit_of_measurement: W
2

Hi, can someone help me with this? Thank you!

3

I have the same issue. I’m using modbus rtu and when a device is offline the other slows down a lot!

is there a way to solve this? Maybe a way to lower the pooling frequency when a device doesn’t answer?

4

To ilustrate this issue, consider this configuration.yalm

modbus:
  - name: modbus_hub1
    type: serial
    port: /dev/serial/by-id/usb-Silicon_Labs_Conversor_D501_Contemp_Bridge_Controller_1703018-if00-port0
    baudrate: 9600
    bytesize: 8
    method: rtu
    parity: N
    stopbits: 1
    timeout: 3
    #delay: 2
    lights:
      - name: "Luz_12_1"
        address: 1
        slave: 12
        write_type: coil
        verify:
        scan_interval: 5
      - name: "Luz_13_3"
        address: 1
        slave: 13
        write_type: coil
        verify:
        scan_interval: 5

When both devices are answering, OK. But when one of them is not available the other starts to respond VERY slowly.

And in the log theres lots of:

2024-04-07 00:43:28.948 ERROR (MainThread) [homeassistant.components.modbus.modbus] Pymodbus: modbus_hub1: Error: device: 13 address: 1 -> Modbus Error: [Input/Output] ERROR: No response received after 3 retries

2024-04-07 00:43:43.888 ERROR (MainThread) [homeassistant.components.modbus.modbus] Pymodbus: modbus_hub1: Error: device: 13 address: 1 -> Modbus Error: [Input/Output] ERROR: No response received after 3 retries

2024-04-07 00:43:58.901 ERROR (MainThread) [homeassistant.components.modbus.modbus] Pymodbus: modbus_hub1: Error: device: 13 address: 1 -> Modbus Error: [Input/Output] ERROR: No response received after 3 retries

2024-04-07 00:44:13.859 ERROR (MainThread) [homeassistant.components.modbus.modbus] Pymodbus: modbus_hub1: Error: device: 13 address: 1 -> Modbus Error: [Input/Output] ERROR: No response received after 3 retries