Emerson recently participated in the ATMO World Summit 2022, a 24-hour event focused on exploring developments in the uses and applications of natural refrigerants. Emily Vilardi, Emerson product marketing manager and I presented a webinar that highlighted Emerson’s commitment to CO2 refrigeration via the launch of new products and our expanded research and development (R&D) efforts. For those unable to attend the event or our session, ATMO has made it available for free on demand.
Emily and I discussed how Emerson is committed to helping facilitate this transition by simplifying the application of CO2 refrigeration through the seamless integration of system components. We focused on three primary areas: compression and variable frequency drives (VFDs), controls and software, and R&D lab investments.
CO2 compression and VFD technology
For the MT transcritical portion of a CO2 transcritical booster system, Emerson offers the Copeland™ 4MTLS transcritical CO2 semi-hermetic compressor in nine displacements from 40,000 to 300,000 BTUs at 60 Hz. These four-cylinder compressors feature onboard diagnostics and have a capacity range from 17.5 to 354 MBH at 20 °F evaporating, 95 °F gas cooler outlet at 60 Hz. In addition, they can be paired with Copeland VFDs, EVM/EVH Series to enable variable-capacity modulation. EVM/EVH drives offer the security of providing 200 percent maximum overload protection for two seconds.
On the LT side, Emerson offers the Copeland ZO(D) subcritical CO2 scroll compressors: ZO for fixed capacity and ZOD (digital) for variable-capacity modulation or their ability to unload capacity down to 10 percent. For example, the ZOD34 is rated for a 34,000 BTU displacement that can modulate (or unload) its capacity to 3,000 BTUs. These subcritical digital scrolls offer a smaller, lighter-weight footprint and don’t require VFDs for capacity modulation. In addition, Copeland MSLS subcritical semi-hermetic compressors are available in displacements from 60,000 to 180,000 BTUs, have a range of 25 to 70 Hz, and are rated for very high standstill pressures.
Integrated CO2 controls
CO2 transcritical booster systems rely heavily on electronic controls to optimize system installation, integrate with cases and high-pressure valves (HPVs), and manage system pressures. Emily explained Emerson’s integrated approach to CO2 controls that enables seamless communication and enhanced visibility to all aspects of system operation.
The soon-to-be released Lumity™ supervisory control for CO2 applications will expand upon the legacy E2e control to offer enhanced CO2 capabilities, reduce programming complexities, and simplify system management via:
- Centralized CO2 suction group control for transcritical booster and parallel compression
- Advanced compressor superheat management for liquid or hot gas injection
- Precise load management and automatic recovery from out-of-range conditions
- Enhanced CO2 system monitoring for system insights
- Oil management for long compressor life
The Lumity E3-CO2 will also leverage the many benefits of the new E3 platform, including: a built-in touchscreen, remote mobile access, and a greatly improved user interface (UI) that brings all critical CO2 system monitoring into one unified view. The control will integrate seamlessly with Emerson’s high-pressure controller and valve driver (XEV20), the soon-to-be released Lumity CC200 case controller, the XM600 series case controllers, and leak detection devices (RLDS and MRLDS).
Investing in the future of CO2
In the ATMO webinar, I also elaborated on how Emerson is helping our customers to prepare for the future of CO2 refrigeration though continued lab investments and R&D efforts. In addition to the CO2 transcritical booster system that has been installed at The Helix Innovation Center since 2016, we’ve recently dedicated more than 100,000 square feet to a CO2-specific supermarket test lab in our facility in Sidney, Ohio. This new lab will be launched this summer and feature:
- 18 display cases from five different manufacturers
- Walk-in cooler and walk-in freezer
- Dry gas and adiabatic gas coolers on the roof
- Wide range of high-ambient system strategies
- Ability to create a 100 percent false load to enable testing at any capacity
These advanced testing capabilities will give Emerson’s application engineers ample opportunities to measure and validate system performance across a full spectrum of application scenarios.
To learn more about how Emerson is helping our customers and the industry to simplify the adoption of CO2 system technologies and optimize refrigeration system performance, please view the ATMO webinar.