SDAA486 September   2026 CC1312R

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 Smart Meter EU Regulations
    2. 1.2 Rotary Metrology Designs
  5. 2Smart Flow Meters and Sub-Metering Devices
    1. 2.1 Heat Cost Allocator (Sub-Metering)
      1. 2.1.1 HCA Key Functions
        1. 2.1.1.1 IrDA Communication Port
        2. 2.1.1.2 Temperature Measurement (Two-Sensor Method)
        3. 2.1.1.3 Segment LCD Support
    2. 2.2 Retrofit Add-On Module for Mechanical Water Meters
      1. 2.2.1 Retrofit Add-On Module Key Functions
      2. 2.2.2 Rotary Flow Metrology Implementation
        1. 2.2.2.1 Optical and Magnetic Rotary Sensing
        2. 2.2.2.2 Inductive Rotary Sensing
      3. 2.2.3 IrDA Wake-Up Detection
    3. 2.3 Smart Rotary Water Meter
      1. 2.3.1 Water Meter Key Functions
      2. 2.3.2 Segment LCD with CapTouch Activation
      3. 2.3.3 Tamper Detection With TMAG5231
      4. 2.3.4 OMS Compliant wM-Bus Communication Sub-system
    4. 2.4 Thermal Meters (Heat / Cold)
      1. 2.4.1 Thermal Meter Key Functions
      2. 2.4.2 Analog Signal Chain for DTM
      3. 2.4.3 Remarkable, Fully Digital Design for DTM
        1. 2.4.3.1 I2C and SMBus-Compatible Digital Sensor for Thermal Meters
        2. 2.4.3.2 1-Wire Compatible Digital Sensor for Thermal Meters
    5. 2.5 Bluetooth Low Energy (BLE) in Flow Meters
    6. 2.6 Influence of CRA on Smart Flow Meters and Heat Cost Allocators
      1. 2.6.1 Achieving CRA Conformance Through Careful System Design
        1. 2.6.1.1 Tamper Detection as a Physical Security Argument
        2. 2.6.1.2 Secure Key Storage
        3. 2.6.1.3 Secure Boot
        4. 2.6.1.4 Authenticated wM-Bus Communication
        5. 2.6.1.5 Secure Firmware Update via Over-the-Air Download (OAD)
        6. 2.6.1.6 Security Event Logging
  6. 3Summary
  7. 4References

1.1 Smart Meter EU Regulations

All smart flow meters also have a pre-defined runtime in the field, often varying between five to ten years and in some markets even longer, after which the meters must be replaced. Any smart meter must provide some form of metrologically controlled display with billing relevant user consumption data. For the EU, this is regulated in the MID 2014/32/EU (Annex I, Essential Requirements) document, stating the display requirements can be met by variety of options. These can be mechanical counters (as in legacy mechanical water meters world-wide), Liquid crystal displays (LCDs) in electronic flow meters, light-emitting diodes (LEDs), or other electronic displays, provided they meet the criteria of the directive for readability, non-ambiguity, and security.

The segment LCD displays are by far the dominant technology in smart flow meters and heat cost allocators. Regulations in the EU do allow us to have the LCD display switched off, but in such case end users must have the possibility to activate it instantly on demand, typically implemented with the help of either a push or capacitive touch button, an optical sensor for lid opening or another user-initiated prompt.