Contemporary Controls offers a range of general-purpose controllers, such as the BAScontrol Series of BACnet/IP Controllers, that use the BACnet IP and MS/TP open protocol for network communications, and depending on the model, have universal inputs and analogue and binary outputs. Furthermore, these freely programmable controllers use Sedona to build applications meeting specific requirements.
Contemporary Controls maintains a library of typical HVAC applications which can be modified using the BAScontrol Toolset. This free set of software tools for a Windows PC includes a Sedona Applications Editor (SAE) for assembling Sedona components onto a wiresheet to create applications, a BASemulator that emulates a controller on a PC, and BASbackup which is used to save and restore controller programs and configurations. Sedona components are deployed in kits. A basic set of kits are shipped with the controller, but other kits can be downloaded from Contemporary Controls or from the Sedona community.
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 is a component-oriented programming language similar to Java or C#. By utilizing this language, developers can create custom components using a Sedona complier that can be downloaded for free from the Sedona Alliance website. Along with the complier is source code, a sample Sedona virtual machine, documentation, and ready-made Sedona components to build upon. All of this is included in a single zip file ready for download.
GreenmediaHD recently used the Sedona Alliance download to create custom components for its advanced rooftop controller. The components were built on Contemporary Controls' RTU38 open controller which is intended for OEMs. Equipped with standard BACnet, a typical Sedona RTU application, and featuring pin and socket connectors that speed controller installation in the RTU, GreemediaHD found the RTU38 an ideal platform for creating custom components to build a proprietary product with specific performance requirements.
With more than 20 years of experience in air conditioning control and optimization, GreenMediaHD developed a kit of new Sedona components to use in their Rooftop Unit Smart Control (RTU-SC) to improve energy efficiency and improve user management and accessibility. The RTU-SC is an energy saving component in the rooftop units of a building HVAC system to modulate, optimize and control the RTU fan speed to improve ventilation rates of an HVAC system.
According to Reynaldo D. Manalich Mazo, software developer at GreenMediaHD, LLC, "If your company has an enthusiastic development team, you can create new custom components and kits for specific types of applications using the Sedona compiler. After you install them onto a Sedona controller, and then integrate them with other Sedona components using a Sedona editor such as SAE, you can create your own specific application controller."
Create Proprietary kits of Components
GreenmediaHD used the Eclipse IDE Software as an editor for developing the new Sedona kit with components.
They created various components inside their custom kit, and installed this kit using the kit manager in SAE. SAE then allowed them to create the application they wanted by assembling all available components onto a wiresheet to create their application specific controller.
When developing their own components, GreenmediaHD imported components that were already available from the Sedona community and used the Sedona programming language to compile new highly integrated components. As a result, system integrators can put a single complex component onto their wiresheet using SAE that internally executes a much larger block of interconnecting logic.
"Otherwise, if you try to put that much logic using existing Sedona blocks (components) in the wiresheet, it will add them to the wiresheet and make the program difficult to follow," said Manalich. "This adds new advantages when making your own proprietary components, first, the program is easier to understand. Second, and for me the most important, you protect your intellectual property, so no one can easily copy your logic."
Create a New User Interface
GreenmediaHD used the controller's Linux capability to embed a second web server to create new web pages in the controller where the variables are grouped by names that are easy for the integrator to understand. For example: Alarms, Setpoint, Energy Values, Protection Limits, Schedules, Main Parameter, etc. This is especially useful for users who are installing and testing the controller on site who are not familiar with this application development, giving them an easier and more reliable way to commission the application and a faster way to finalize installation.
Caption: Custom Webpages developed by GreenMedia allow tuning the controller along with viewing trends
"Besides improving the commissioning process of the specific application, the added web server makes the controller more autonomous and reliable," said Manalich. "It can work standalone without any BMS, and the user can monitor the different variables and modify set-points using any smart device connected in the same local Ethernet network that has a browser, such as a tablet, smart phone, laptop, or any computer."
For more information about Sedona technology, visit Sedona Alliance, or refer to BAScontrol Series of BACnet/IP Controllers USING SEDONA TO CREATE AN OPEN CONTROLLER (PDF).
For information on the GreenMediaHD Roof Top Unit Smart Control (RTU-SC), visit http://greenmediahd.com/rooftop.