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Sedona Macro Components Reduce Memory Space

Sedona is an open-source software environment designed to make it easy to build smart, networked, embedded devices which are well suited for implementing control applications. The Sedona language facilitates component-oriented programming where components are assembled onto a wiresheet, configured, and then interconnected to create applications. The technology is in the public domain and can be found at Sedona Alliance.

As a Sedona developer, Contemporary Controls has created several product lines based on Sedona, such as the BASautomation line of BAScontrol and Micro PC Edge BACnet-compliant open controllers, the BAScontrol Toolset for unrestricted use in program development and archiving, and HVAC applications with sophisticated macro components. Pre-Built applications make it easy to utilize our controllers in constant volume air-handling, fan coil, and heat pump applications.

The macro components are highly integrated components that reduce wiresheet logic memory size and complexity, thereby reducing available application memory space. Using the BAScontrol Toolset, a systems integrator can put a single complex component onto their wiresheet that internally executes a much larger block of interconnecting logic. This reduces the program's complexity and makes it easier to follow. Systems integrators and developers can also use the macros to create custom components for an application-specific device. The logic is hidden to protect intellectual property for proprietary designs.

Constant Volume Air Handlers

Contemporary Controls has replaced the constant volume CvRTU series of pre-built applications with a new CvAHU series which includes three new macros—Staged Heat/Cool, Wall Setter, and Economizer. The targeted constant volume applications have not changed.

  • Staged Heat Cool combines one or two-stage heating/cooling binary outputs, supply fan stop/start control, fan proof protection, buffered analog outputs, and emergency shutdown.
  • Wall Setter manages inputs from either digital or analog type wall setters which provides space temperature, setpoint, humidity, and CO2 control.
  • Economizer-English Units is a comprehensive "virtual" airside economizer with configuration options that include single or dual dry-bulb, single or dual enthalpy, demand control ventilation (DCV), powered exhaust fan, and a Purge mode.

2-Pipe or 4-Pipe Fan Coils

One of the most common HVAC applications is the fan coil. There are two basic applications with the first version supporting a 20-point controller and the second supporting a 22-point controller. The supply fan can be single speed, multi-speed, or variable speed. Dependent upon the piping, the fan coil can be dedicated to either chilled water cooling or hot water heating, or simultaneous heating and cooling. There is a choice of modulating or staged heating/cooling up to two stages. An output exists for binary ventilation control.

Constant Volume Heat Pumps

For a decarbonization strategy, heat pumps are attractive. There are four possible applications with the fourth one designed for a 20-point controller. All are intended for a single-speed supply fan. The exhaust port can be barometric, powered, or none at all. There is a single stage of DX heating or cooling. If auxiliary heating is required in colder climates, it can be accomplished with modulating or dual-staged heating. An output exists for binary ventilation control.

For more information about the CvRTU series and its three new macros or our other pre-built applications, go to Pre-Built Applications.


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