Template error - unsupported operand type(s) for +

Configuration
1

Hi,
Can someone help me with the following error? it looks like + is not supported but the sensor works?

TemplateError('TypeError: unsupported operand type(s) for +: 'NoneType' and 'NoneType'') while processing template 'Template<template=({{ state_attr('sensor.solax_rest_cloud', 'powerdc1') + state_attr('sensor.solax_rest_cloud', 'powerdc2') }}) renders=72>' for attribute '_attr_native_value' in entity 'sensor.solax_cloud_solar_panel'

I already added the availability, but that didn’t solve the issue.

sensor:
    - name: "Solax Cloud Solar Panel"
      state: >-
        {{ state_attr('sensor.solax_rest_cloud', 'powerdc1') + state_attr('sensor.solax_rest_cloud', 'powerdc2') }}
      unit_of_measurement: "Wh"
      availability: >-
        {{ states('sensor.solax_rest_cloud') not in ['unavailable', 'none', 'unknown'] }}

when I test the state in the template tester, the same as the sensor uses but also seperate, the result is:

image
image1312×321 25.1 KB

Can powerdc2 be the cause? which is almost 0 all the time?

2 
{{ state_attr('sensor.solax_rest_cloud', 'powerdc1')|float(0) + state_attr('sensor.solax_rest_cloud', 'powerdc2')|float(0) }}

States and attributes are strings by default, you need to cast them to float or int to do math, and you need to provide a default value in case it’s not available or contains a value that can’t be converted. So we use float(0) which means if it can’t be converted it will just be 0.

3

Actually, just states. Attributes can be any object type.

‘NoneType’ and ‘NoneType’’ implies the attributes were unknown at some point.

A better availability template would be:

      availability: >
        {{ state_attr('sensor.solax_rest_cloud', 'powerdc1')|is_number and
           state_attr('sensor.solax_rest_cloud', 'powerdc2')|is_number }}
1 Like
4

The new ‘add’ might be useful here

Filter add(arg) will convert the input to a number and add it to arg. Useful in list operations in conjunction with map.

Templating - Home Assistant.

5

Nah. This is a simple addition of two sensors. No selecting and mapping.

1 Like