Error in template. Please help

Hi,

I have a 3 phase modbus meter which gives me these values:
sensor.sdm530_1_ph1_power
sensor.sdm530_1_ph2_power
sensor.sdm530_1_ph3_power
I want to know the maximum (and also minimum) power values. I tried to use the template below in my configuration.yaml, but these values won’t hold the max power value. The value of sensor.max_power1 is the current power and keep changing all the time. Please help me solve this. Thanks in advance.

Best regards,
Erik

  - trigger:
      - platform: state
        entity_id: sensor.sdm530_1_ph1_power
        id: 'change'
    sensor:        
      - name: Max Power Ph1
        state: >
          {% set maxpwr1 = states('sensor.sdm530_1_ph1_power')|float(None) %}
          {% set maxph1 = states('sensor.max_power1')|float(None) %}
          {% if  maxpwr1 != None  and (maxph1 == None
            or maxpwr1 > maxph1) %} {{ maxpwr1 }}
          {% else %} {{ maxph1 }} {% endif %}
        unit_of_measurement: W
        device_class: power
  - trigger:
      - platform: state
        entity_id: sensor.sdm530_1_ph2_power
        id: 'change'
    sensor:        
      - name: Max Power Ph2
        state: >
          {% set maxpwr2 = states('sensor.sdm530_1_ph2_power')|float(None) %}
          {% set maxph2 = states('sensor.max_power2')|float(None) %}
          {% if  maxpwr2 != None  and (maxph2 == None
            or maxpwr2 > maxph2) %} {{ maxpwr2 }}
          {% else %} {{ maxph2 }} {% endif %}
        unit_of_measurement: W
        device_class: power
  - trigger:
      - platform: state
        entity_id: sensor.sdm530_1_ph3_power
        id: 'change'
    sensor:        
      - name: Max Power Ph3
        state: >
          {% set maxpwr3 = states('sensor.sdm530_1_ph3_power')|float(None) %}
          {% set maxph3 = states('sensor.max_power3')|float(None) %}
          {% if  maxpwr3 != None  and (maxph3 == None
            or maxpwr3 > maxph3) %} {{ maxpwr3 }}
          {% else %} {{ maxph3 }} {% endif %}
        unit_of_measurement: W
        device_class: power

You can use the Statistics Sensor to calcuate the “value-max” over a period. Your current code superficially looks like it will work and will have the maximum “ever”. The only obvious thing is if both are None, then the result will be null. If you paste the template into Dev Tools, do you get an error?