Working Home Assistant Custom RFID Spool Setting (AMS Support)

[MrKuenning]

Guide to Set Up RFID Tag Scanning and Bambu Lab A1 Filament Settings in Home Assistant

Recently, the Bambu Labs Home Assistant integration introduced the ability to push spool information, such as filament type and color, to the A1 printer. I wanted to take this a step further by automating the process using RFID tags, with full support for AMS (Automatic Material System).

The concept is simple: place RFID tags on each AMS tray, and by swiping your phone over a tag, you can select the tray. Then, by scanning an RFID sticker on the spool you’re using, the configuration is automatically pushed to the printer. The whole thing only costs a few dollars worth of RFID stickers.

The automation works by storing the data for each spool as a template sensor. When an RFID tag is scanned, it matches the unique tag ID and looks up the associated data. While I initially hoped to use a library or lookup table instead of unique sensors, I couldn’t find a way for Home Assistant to support that approach.

This guide will walk you through the steps to set up RFID tag scanning for managing Bambu Lab A1 spool and tray locations, using Home Assistant automations and sensors.

Step 1: Create Sensors in templates.yaml

Define the tray and spool sensors in your templates.yaml file. These sensors will represent the RFID tags scanned for each tray and spool. You will need to define one of these per spool locations. For my A1 that was 5, each AMS and the external spool.

• The name can be anything you want.

• The state is the RFID tag ID

• attribute entity_id must match the entity name of your tray in the Bambu Integration

• attribute name is what ever you want

    ####################
    ### Tray Lookup  ###
    ####################
    
      - sensor:
          - name: Tag A1 AMS Tray 1 # Green
            state: "1cf4f3de-c5ca-4580-a706-ab48edf9cf07"
            attributes:
              entity_id: "sensor.bambu_a1_ams_tray_1"
              name: "AMS Tray 1"
    
          - name: Tag A1 AMS Tray 2 # Purple
            state: "ead00e5f-db5c-4a5b-aad3-41629a540536"
            attributes:
              entity_id: "sensor.bambu_a1_ams_tray_2"
              name: "AMS Tray 2"
    
          - name: Tag A1 AMS Tray 3
            state: "bad00e5f-db5c-4a5b-aad3-41456a540536"
            attributes:
              entity_id: "sensor.bambu_a1_ams_tray_3"
              name: "AMS Tray 3"
    
          - name: Tag A1 AMS Tray 4
            state: "gad00e5f-db5c-4a5b-aad3-413rdg540536"
            attributes:
              entity_id: "sensor.bambu_a1_ams_tray_4"
              name: "AMS Tray 4"
    
          - name: Tag A1 External Spool
            state: "fad00e5f-db5c-4a5b-aad3-417ughj40536"
            attributes:
              entity_id: "sensor.bambu_a1_spool"
              name: "External Spool"
  

For the spools themselves, you will need to define a sensor per spool.

• The name can be anything you want.

• The state is the RFID tag ID

  The action that Home assistant uses to write to a tray looks like this.
  So these are the variables we are storing in the sensor.
  I recomend looking at your tray attributes on your Bambu Integration.

  action: bambu_lab.set_filament
  target:
  entity_id: sensor.bambu_a1_ams_tray_2
  data:
  tray_info_idx: P0e61dbf
  tray_color: FF0000FF
  tray_type: PLA
  nozzle_temp_min: 220
  nozzle_temp_max: 220

• attribute tray_info_idx you will need to get this value from the tray attributes on your Bambu Integration.

• attribute common_name Easy to read version of above

• attribute tray_color Hex Color

• attribute common_color Easy to read version of above

• attribute tray_type must match the filament type in the Bambu Integration

    #####################
    ### Spool Lookup  ###
    #####################
    
      - sensor:
          - name: "Tag Spool - Elegoo PLA+ - Red"
            state: "e9422f8e-aed3-4718-85a8-f3f9fb7f99be"
            attributes:
              tray_info_idx: "P0e61dbf"
              common_name: "Elegoo PLA +"
              tray_color: "FF0000FF"
              common_color: "Red"
              tray_type: "PLA"
              nozzle_temp_min: "220"
              nozzle_temp_max: "220"
    
          - name: "Tag Spool - Generic PETG - Blue"
            state: "t9422f8e-aed3-4718-85a8-f3f9fb7f455e"
            attributes:
              tray_info_idx: "Q1f72eca"
              common_name: "Generic PETG"
              tray_color: "0000FFFF"
              common_color: "Blue"
              tray_type: "PETG"
              nozzle_temp_min: "240"
              nozzle_temp_max: "250"
  

Step 2: Create Groups in groups.yaml

The sensors we made above need to be added to groups. We use these groups as a verification that the Automations match and should run.

         tray_info_group:
           name: Bambu A1 Tray Info Lookup Group
           entities:
             - sensor.tag_a1_ams_tray_1
             - sensor.tag_a1_ams_tray_2
             - sensor.tag_a1_ams_tray_3
             - sensor.tag_a1_ams_tray_4
             - sensor.tag_a1_external_spool
         
         spool_data_group:
           name: Bambu A1 Spool Data Lookup Group
           entities:
             - sensor.tag_spool_elegoo_pla_red
             - sensor.tag_spool_generic_petg_blue

Step 3: Create an Input Select Helper

In the UI Helper section, create an input select helper to store the available tray and spool entities. This will allow your automation to select the appropriate tray/spool based on the RFID tag.

The sensors must match the current name of your trays in your Bambu Integration.

         input_select:
           bambu_a1_set_spool:
             name: "Select Bambu A1 Spool Location"
             options:
               - sensor.bambu_a1_ams_tray_1
               - sensor.bambu_a1_ams_tray_2
               - sensor.bambu_a1_ams_tray_3
               - sensor.bambu_a1_ams_tray_4
               - sensor.bambu_a1_spool

Step 4: Create Automation 1 – RFID - Select Bambu Lab A1 Spool Location

This automation will trigger when a tag is scanned, check if the tag is in the tray_info_group, and update the selected tray or spool in the input_select.bambu_a1_set_spool helper.

Automation Configuration

Add the following automation: NOTE: I have a telegram message that tells me what spool is selcted via notification. You can use your own notification type, or remove it.

         alias: RFID - Select Bambu Lab A1 Spool Location
         description: ""
         trigger:
           - event_type: tag_scanned
             trigger: event
         condition:
           - condition: template
             value_template: >
               {{ trigger.event.data.tag_id in state_attr('group.tray_info_group', 'entity_id') | map('states') | list }}
         action:
           - variables:
               tag_id: "{{ trigger.event.data.tag_id }}"
               sensor_entity: >
                 {% set entity_ids = state_attr('group.tray_info_group', 'entity_id') %}
                 {% for entity_id in entity_ids %}
                   {% if states(entity_id) == tag_id %}
                     {{ entity_id }}
                   {% endif %}
                 {% endfor %}
               sensor_name: "{{ state_attr(sensor_entity, 'name') }}"
               entity_id_for_select: "{{ state_attr(sensor_entity, 'entity_id') }}"
           - data:
               message: |
                 Spool location set to: {{ sensor_name }}
             action: telegram_bot.send_message
           - target: YOUR TELEGRAM ID
               entity_id: input_select.bambu_a1_set_spool
             data:
               option: "{{ entity_id_for_select }}"
             action: input_select.select_option

Step 5: **Create Automation 2 – RFID - Set Bambu Lab A1 Filament **

This automation will trigger when a tag is scanned, check if the tag is in the spool_data_group, and then set the filament parameters for the selected spool. It will also send a notification with the filament settings.

Automation Configuration

Add the following automation: NOTE: I have a telegram message that tells me what spool is selcted via notification. You can use your own notification type, or remove it.

         alias: RFID - Set Bambu Lab A1 Filament (Tag Scanner)
         description: ""
         trigger:
           - event_type: tag_scanned
             trigger: event
         condition:
           - condition: template
             value_template: >
               {{ trigger.event.data.tag_id in state_attr('group.spool_data_group', 'entity_id') | map('states') | list }}
         action:
           - variables:
               tag_id: "{{ trigger.event.data.tag_id }}"
               sensor_entity: >
                 {% set entity_ids = state_attr('group.spool_data_group', 'entity_id') %}
                 {% for entity_id in entity_ids %}
                   {% if states(entity_id) == tag_id %}
                     {{ entity_id }}
                   {% endif %}
                 {% endfor %}
               tray_info_idx: "{{ state_attr(sensor_entity, 'tray_info_idx') }}"
               tray_color: "{{ state_attr(sensor_entity, 'tray_color') }}"
               tray_type: "{{ state_attr(sensor_entity, 'tray_type') }}"
               nozzle_temp_min: "{{ state_attr(sensor_entity, 'nozzle_temp_min') }}"
               nozzle_temp_max: "{{ state_attr(sensor_entity, 'nozzle_temp_max') }}"
               common_name: "{{ state_attr(sensor_entity, 'common_name') }}"
               common_color: "{{ state_attr(sensor_entity, 'common_color') }}"
           - choose:
               - conditions: []
                 sequence:
                   - data:
                       message: >
                         Filament settings set for {{ common_name }} (Color: {{ common_color }}).
                     action: telegram_bot.send_message
                   - action: bambu_lab.set_filament
                     target:
                       entity_id: "{{ states('input_select.bambu_a1_set_spool') }}"
                     data:
                       tray_info_idx: "{{ tray_info_idx }}"
                       tray_color: "{{ tray_color }}"
                       tray_type: "{{ tray_type }}"
                       nozzle_temp_min: "{{ nozzle_temp_min }}"
                       nozzle_temp_max: "{{ nozzle_temp_max }}"
             default:
               - data:
                   message: Invalid RFID tag scanned.
                   target: 1279266734
                 action: telegram_bot.send_message

Step 6: Add New Spools

Going forward you just need to add a new spool sensor with your new Tag IDs and add it to the spool_data_group.

Step 7: Test and Debug Your Setup

After completing the configuration in Step 5, it's important to test and debug your automation to ensure everything is working as expected. Follow these steps to test and troubleshoot your system:

1. Trigger the Automation

• Scan one of your RFID tags and observe if the automation is triggered.
• Check if the correct spool and tray information are set and if the automation runs without errors.

2. Check the Telegram Notifications

• After scanning the RFID tag, ensure that you receive a notification on Telegram with the correct filament settings.
• If the notification does not appear, make sure the telegram_bot.send_message action is correctly configured with the correct target (your chat ID).

3. Verify Input Select is Updated

• Ensure that the input_select.bambu_a1_set_spool entity is updated to reflect the selected spool or tray based on the scanned tag.
• Check if the correct entity is selected after each tag scan and verify that the options match the entities you set in the input_select.

4. Debugging Automation

• If the automation isn't working as expected, enable Debug Mode in Home Assistant to view logs and understand what might be going wrong.

• Go to Configuration > Logs in Home Assistant and review any errors related to the automation.

• You can also add debug actions to the automation to send logs to Telegram for real-time troubleshooting. For example:

              action:
                - data:
                    message: "Debugging: Tag ID: {{ trigger.event.data.tag_id }}"
                  action: telegram_bot.send_message
  

5. Check the Sensor States

• Verify that the sensor states for your RFID tags and spools are correctly set in Home Assistant.
• Go to Developer Tools > States and check the values for sensor.tag_a1_ams_tray_1, sensor.tag_a1_ams_tray_2, etc., and ensure they match the tag IDs you are scanning.

6. Verify Group Entities

• Check that the group entities (group.tray_info_group and group.spool_data_group) are populated with the correct sensors and entities.
• If an entity is missing from the group or if the group isn’t configured properly, the automation will not trigger or may fail - Go to Configuration > Groups and verify that the correct entities are listed under these groups.

7. Adjust if Necessary

• If something doesn’t work as expected, revisit the automations, variables, or template conditions. You may need to adjust the logic slightly to match your exact use case.
• Testing with different tags and spools will help confirm if everything is running smoothly.

Once the automation is tested and debugged, your setup should be fully functional. You’ll now have an efficient system for scanning RFID tags and automatically setting filament parameters and tray locations.