What's wrong with this?

Configuration
1

I’m trying to add 4 sensors together. Can you please tell me what’s wrong with this?

  - platform: template
    sensors:
    test:
      entity_id: Total.Power
    name: "Total_power"
    value_template: "{{((state_attr('sensor.a_breaker','watt_seconds') + state_attr('sensor.b_breaker','watt_seconds')+ state_attr('sensor.c_breaker','watt_seconds') + state_attr('sensor.d_breaker','watt_seconds')| int / 3600000) | round(1) )}}"
2

You have only converted the last sensor state to a number. Al the otheres are still strings.

3

Thank you for your help. Can you please show me the correct why to do this?

5 
value_template: "{{((state_attr('sensor.a_breaker','watt_seconds')|float(0) + state_attr('sensor.b_breaker','watt_seconds')|float(0) + state_attr('sensor.c_breaker','watt_seconds')|float(0) + state_attr('sensor.d_breaker','watt_seconds')|float(0) / 3600000) | round(1) )}}"
6

I really appreciate your help! I’m getting a number that is obviously to high 1,721,050,648,982.3 watts

  - platform: template
    sensors:
      power_total:
        friendly_name: "Power - Total"
        value_template: "{{((state_attr('sensor.a_breaker','watt_seconds')|float(0) + state_attr('sensor.b_breaker','watt_seconds')|float(0) + state_attr('sensor.c_breaker','watt_seconds')|float(0) + state_attr('sensor.d_breaker','watt_seconds')|float(0) /3600000) | round(1) )}}"
#        unit_of_measurement: 'watts'
7

What are the states of your sensors?

8

Watts

518.0 W

9

Put this in the Developer Tools Template editor and post the result:

{{ state_attr('sensor.a_breaker','watt_seconds') }}
{{ state_attr('sensor.b_breaker','watt_seconds') }}
{{ state_attr('sensor.c_breaker','watt_seconds') }}
{{ state_attr('sensor.d_breaker','watt_seconds') }}
10

533043068959
719922681383
468174668840
142778494000

11

Well they are a bit different from your stated 518.0.

The problem is that you are only dividing the last sensor in the template by 3600000. Put some brackets around the numerator (top part of the division).