Controlling Transcritical R774 Booster Systems

VS 3010 CT - Controlling Transcritical R774 Booster Systems (Photo: Eckelmann AG)

Eckelmann Presents the VS 3010 CT CO2 Pack Controller

Wiesbaden, 27/03/13: Eckelmann has expanded its E*LDS control system with the addition of a pack controller for the transcritial operation of refrigeration systems using the natural refrigerant CO2 (R744) in normal-temperature refrigeration (NT). The VS 3010 CT is used together with a VS 3010 for low-temperature refrigeration (LT) in booster operation. CT stands for “CO2 transcritical”.

All the functions required for transcritical operation are integrated in the controller. This ensures a high degree of operational reliability and control quality. In other words: no separate components are required, e.g. for the regulation of the gas cooler circuit, and regulation is thus completely independent of possible disturbances to the field bus communication. Refrigeration electronics could hardly operate more reliably or independently!

The VS 3010 CT regulates the suction pressure (LP), the medium pressure (MP via the pressure in the refrigerant receiver), the high pressure (HP), and the gas cooler. In transcritical mode the optimal high pressure required for a high COP is continually calculated and used as a control value. This is necessary as above the critical point for CO2 (ϑ = 30.98 °C; p = 73.75 bar) there is no clear physical correlation between pressure and temperature.

The first commercial refrigeration systems are already operating successfully with the new E*LDS VS 3010 CT pack controller.

Thanks to the high condensation end temperatures, the natural refrigerant CO2 is ideally suited for heat recovery, e.g. in order to heat process water or heating circuit water. This enables a further, considerable improvement to the energy efficiency of the system as a whole. Whether connected via the VS 3010 CT’s analogue input to Eckelmann’s multifunctional DDC GLT 3010 for building automation tasks, or other control technology, the heat recovery setpoint can be infinitely adjusted via 0-10 V signal to meet the requirements of the building control technology.

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