What is in this article?:
- Shifting Cooling Control From the Rack to the Case
- Electrical Installation Reduces First-time Costs
- Improved Startup and Commissioning
- Eyes Into the System Help to Optimize Maintenance
- It Pays to Make the Shift
The Advantages of Case Control Refrigeration Architecture
Case control architecture enables control of all refrigeration case elements to deliver precise optimization across the entire refrigeration system.
Electrical Installation Reduces First-time Costs
Retailers may associate case control systems with installation challenges and unwanted commissioning costs. In reality, installation is not only very simple, it even reduces installation costs. A closer look at the electrical architecture demonstrates where savings can be achieved (see Figure 1).
Centralized systems distribute control from the rack house or electrical room, and require excessive electrical runs to support the installation. Electronic control systems, such as input and relay boards, are located back in the rack house. Multiple low voltage electrical lines for temperature sensors (shown in the diagram as red lines) are wired from the rack house to each case on the floor; these are often referred to as “home runs.” Load controls, such as lights and anti-sweat heaters, are located in electrical panels.
In contrast, modern case control refrigeration systems simplify electrical configurations and provide all refrigeration controls at the individual case level. A daisy chain of temperature sensors is consolidated into a single, communications line, eliminating the need for multiple “home runs” to the rack house. Load switching occurs in the case itself (lights, fans, anti-sweats, etc.), reducing the number of electrical lines needed to run from the electrical panel to the refrigeration cases on the merchandising floor.
These significant electrical installation savings include:
- Reduction of electrical distribution feeder wiring
- Reduction and/or elimination of circuit panels and breakers
- Minimization of case field wiring
Since case electronics are mounted at the OEM (case controllers, sensors) during factory checkout, it eliminates much of the field work during installation … and leads to shorter commissioning time. But, with these changes to the electrical design and construction, retailers need to employ contractors who are familiar with this electrical architecture to realize the efficiencies of the case control architecture.
Note that this architecture requires an electronic case control system and EEV per each individual case. While this represents an increased cost for case electronics, the simplified electrical installation, startup costs and ongoing energy-reduction benefits more than compensate retailers for their investment.