Displacement Free Cooling

The DFC-350 and DFC-450 operate as displacement free cooling systems using gravity airflow. The smaller DFC-350 has a cooling capacity of approximately 3 kW with a maximum temperature difference of 5°C. The larger DFC-450 has a cooling capacity of approximately 5 kW with a 5 K temperature difference.

Mode of operation

Clean and cool fresh air blown in slowly through a monitored F5 or F7 filter falls to the floor of the equipment room and presses the warm air of the base station upward. A motor-driven exhaust air damper is installed in an exterior wall at a height of 1.6 m. The warm exhaust air flows out through this damper. The room is cool at the bottom, where the batteries are located, and somewhat warmer further up.

DFC-350 / DFC-450

48 VDC and 230 VAC versions are available for both systems. This highly efficient cooling technology is effective in equipment rooms with floor areas up to about 18 m², which is enough for base stations installed in containers with a length of 6 to 7 m.

With a maximum emitted noise level of 35 to 43 dB(A) measured at a distance of 3 m, compliance with stringent noise level regulations is possible even at night in pure residential areas.

The maximum electrical power consumption with a 48 VDC supply is 40 W, yielding energy savings of more than 90% in comparison to conventional air conditioning systems. That can easily reduce annual energy expenses by 1,200 to 1,500 euros per base station.

Installation of these systems is easy. They are always located in the equipment room, where they are protected against vandalism. An air maze can be fitted over the supply air opening to act as a pre-filter, making the systems suitable even for locations with a high dust burden, such as on silos or along farm or forest roads. The DFC systems are controlled by the same CC-3000 controller as the Flexibox 900, with all functions available.

The manufacturer’s warranty is 24 months, which can be extended to as much as 5 years for a small fee, subject to periodic maintenance. The MTBF of the high-grade system components is much longer.