Space upgrades are a necessity to ensure that older buildings remain safe, functional, and cutting-edge for the users. As part of my role as an owner’s project manager for a large hospital, one of my recent projects has been an upgrade to the finishes of several operating rooms. This post will discuss the coordination and construction effort involved for such a project, as well as some potential challenges.
In part 1 and part 2 of this series on RS-485 we covered the basics. Let’s take some of that knowledge and talk about what most often goes wrong with RS-485. I want to give you the ability to red flag common mistakes and some knowledge that will help repair the most common issues. I am going to take some of the knowledge we gained from the last two posts and put it into context for both existing RS-485 installations and new ones. I’ll discuss this in the form of red flags that will trigger the discussion.
On a current project that Cx Associates is consulting on, the client has a goal of reducing their building’s peak demand charge. For commercial customers, peak demand charges are usually charged based on the peak kW demand of the building or facility during a certain time (e.g. 1-4 PM) of the day. If there is a peak kW outside of this specific time frame, there is no “peak demand charge” from the utility for this peak kW.
In Part One One of this series of posts on RS-485, I gave a high level introduction to the structural and electrical components of RS-485 networks. This week I’ll elaborate on those concepts and delve a little more deeply into some of the industry terminology and how it applies to those concepts. As always, please feel free to drop a comment if you have any questions or want further discussion on any of this information.
What is RS-485 and what does it have to do with buildings or building controls? If you’re asking this question either you’re just curious, or maybe something isn’t working quite right and you’re Googling to find an answer. Either way, I plan on giving you a high level understanding of RS-485 in this post, and how having a better grip on how it works can help building operators and controls contractors control their building more effectively.
Metering equipment, such as light loggers, temperature loggers, and AC current loggers can be very useful tools and sometimes necessary in the world of energy efficiency consulting. They can provide useful data on how equipment is operating and performing. I have written about metering in previous blog posts including one called “EM&V Metering: Right Place, Right Time, Right Duration” where I described the importance of identifying the correct way of deploying meters. In this post I am going to discuss the importance of verifying that meters or loggers are working correctly even before a metering plan is developed or the devices are deployed, as well as the importance of ensuring that the correct sensors are chosen for the application.
Chilled beams have been common in European building HVAC systems for decades, but they are just getting popular in the U.S. These units fit in a drop ceiling or can be hung flush to the ceiling and contain a chilled/hot water coil and, in the case of active beams, a duct bringing in ventilation air.
If you’ve worked in the Building Automation Systems (BAS) industry, you’ve probably heard of LonWorks, BACnet, and Modbus. These three open system networking technologies have been the foundation of most building automation systems over the last decade. They allow devices from different manufacturers to communicate data without issue (most of the time) so that a building’s chiller, boiler, and pumps may all work together as one system to give a building owner an integrated system that enables a high level of functionality.
We are in the process of wrapping up an energy efficiency and building automation system upgrade project at an office building. The project involved converting an older boiler/tower heat pump loop system with constant speed pumping to variable flow, and the installation of a modern building automation system (BAS) with new energy efficient control sequences. The project has been a big success however, the project team experienced some challenges in really “dialing in” the controls. The main obstacle is that remote access to the BAS had not yet been established. Having remote access to building controls during the later stages of construction provides many benefits—including being able to monitor system performance remotely, review alarm logs and historical trends to identify problems, and even make adjustments on-the-fly to tune system parameters correctly. Without remote access we would have had to drive to the building, request access to a network closet from the property manager, plug into the server in a closet, and then spend time in a tight space trying to accomplish our goals before unplugging and heading back to the office. Needless to say it is not convenient to do frequently, and is expensive.
On a recent project at a large hospital Cx Associates examined the feasibility of consolidating two air handlers into one single air handler. One of the air handlers is nearing the end of its useful life, and is the reason this project was brought to Cx Associates. While making an in-kind replacement was looked at, the replacement of this air handler presented an opportunity to replace another that was also aging, and located in a position that would be difficult to replace in the future. By combining the two air handlers into a single air handler there was an opportunity to essentially upgrade two air handlers at once at a lower cost than replacing them individually at different times. Maintenance advantages can also be realized by reducing the number of air handlers to maintain in the facility by one.