CuRA - Customized Register Assignment

Define Modbus registers flexibly, individually and project-specifically

In building automation, it's not just precision that counts - it's also efficiency.
Anyone who works with BMS systems, DDC controllers or integration projects on a daily basis knows that standardized register tables are important, but not always optimal.

With CuRA (Customized Register Assignment), we have developed a function that is currently only available in this form from S+S: The individual, project-specific definition of Modbus registers for each individual data point - flexible, project-specific and fully compatible with existing system architectures.

It is not a "nice to have".
CuRA is the result of our consistent development work - from practice for practice.

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Why we developed CuRA

In countless conversations with system integrators, planners and BMS managers, we hear this again and again:

"The device fits - but the register structure doesn't."

Standardized Modbus tables are useful. But projects are not always standardized. Fixed address logics exist, especially in existing buildings or in large BMS systems:

  • Defined 3xxxx and 4xxxx ranges
  • Historically grown register plans
  • Specifications of international BMS manufacturers
  • Internal integration standards of large project developers

And that has meant every time so far:

  • Elaborate mapping
  • Additional documentation
  • Adaptation of the BMS
  • Time lost during commissioning

As the development department at S+S, we asked ourselves:

Why does the project have to adapt to the device - and not the other way around?

CuRA was created precisely from this customer perspective.

  • What does CuRA mean in concrete terms?

    Register addresses are permanently defined in classic Modbus structures. This means that

    • Each temperature has a predefined address
    • Each setpoint is firmly anchored
    • Each fan stage follows the standard structure

    This works - as long as the higher-level system is structured in exactly the same way. In practice, however, things often look different:

    • Existing BMS structures with historically grown register plans
    • Standardized integration specifications from major building management system manufacturers
    • Project specifications with fixed address ranges
    • Retrofit situations in which existing structures must be retained

    This is exactly where CuRA comes into play.

  • What makes CuRA unique

    With CuRA, the Modbus registers of a Rymaskon® device individually. Each relevant data point can be flexibly assigned to a desired register area.

    Examples:

    • Room temperature → Freely definable holding address
    • Setpoint → individually adjustable
    • Fan stage → can be integrated on a project-specific basis
    • Presence status → adaptable to existing BMS structure
    • CO2, VOC or humidity values → structurally identical to existing sensors

    This means that the device is not just integrated - it adapts completely to the project.

Why is this so valuable?

  1. Time savings during commissioning
    - No or little adaptation of the BMS structure necessary.
    - No additional mapping tables.
    - No complicated gateways or detours.
    - Reduce the number of queries: Arrangement of important registers next to each other (1, 2, 3, 4 instead of 100, 400, 800, 1200) > one query instead of four.

    This significantly reduces planning effort and commissioning time.

  2. Ideal for retrofit projects
    In existing buildings, the register structure is often non-negotiable.
    With CuRA, new Rymaskon® devices can be precisely integrated into existing structures - without system conversion.

  3. Standardized project structure
    Especially for larger projects or series installations (e.g. hotel, office complex, residential complex), CuRA provides:
    - Standardized address logic
    - Clear documentation
    - Reusable GLT templates

  4. Maximum freedom of integration
    CuRA turns a standardized device into a project-specific solution - without the need for custom-made products.

Contents

Technical background to CuRA Practical example CuRA CuRA + W-Modbus - Maximum flexibility

Technical background

Our Rymaskon® support 1000 devices:

  • Modbus RTU (RS-485)
  • W-Modbus (Wireless)
  • Extensive data and configuration registers
  • Holding, input and coil registers
  • Read and write functions via GLT

The devices have a structured register table that defines all available data points. With CuRA, this standard structure is adapted to the specific project - without changing the internal logic of the device.
The function is anchored as a central feature in the product description

Example from practice

A system integrator works with a BMS that specifies the following structure:

  • 30000 range → Actual values
  • 31000 range → Setpoints
  • 32000 range → Status messages

By default, Modbus devices are often in a mixed range.

Without our feature, this means:

  • Adaptation of the BMS
  • Special programming
  • Increased commissioning time

With CuRA, we can easily customize the areas according to our needs:

  • Temperature actual value → 30001
  • Setpoint → 31001
  • Fan status → 32001

Result:
✔ No GLT adjustment
✔ Faster commissioning
✔ Reduced documentation effort
✔ Project deadlines met

CuRA + W-Modbus - Maximum flexibility

CuRA is particularly exciting in combination with our W-Modbus-system. Because:

  • Radio network remains standardized
  • The gateway handles communication and system integration
  • Register structure remains fully customizable

Especially with hybrid networks (RTU + W-Modbus), it becomes clear how important a well thought-out system architecture is to ensure maximum flexibility.

How is CuRA configured?

The configuration can be carried out via:

  • Configuration software (S+S Configuration Tool)
  • Modbus register
  • Project-specific parameterization

Important:
The register adjustment is structured and documented - for a clean handover to the planner and integrator.

Conclusion: Why CuRA is typically S+S

CuRA stands for:

✔ Maximum freedom of integration
✔ Reduced project runtimes
✔ Perfect GLT adaptation
✔ Clean retrofit integration
✔ Professional system architecture

With CuRA, we turn a standardized Modbus device into an individual solution - without the need for custom development.

And thus exemplary for our claim:

We do not develop products that only work.
We develop solutions that simplify projects.

And that is precisely why system integrators, planners and BMS manufacturers have been relying on S+S Regeltechnik.