Total facility power consists of the power required to run the IT equipment and all other equipment, such as chiller compressor, cooling tower and CRAH
fans, pumps, lighting, and UPS losses (Belady et al.
We're seeing about a 100 kWh drop in monthly power utilization which is about a 10 percent reduction in our usage overall at the facility, attributable to the new chillers, pumps and CRAH
units when compared to the former chillers," Williams says.
The model also has six CRAH
units to serve the UPS rooms.
unit has a controllable flow valve associated with it, which, along with the heat exchanger, can be represented as a flow resistance.
unit fans of the air-cooled model has no counterpart in the liquid-cooled model.
, AHU or power to Part or all flow from them of the data CRAHs
or AHUs center without cooling other than fans in IT equipment Temperature II.
characteristics mentioned above are based on tests with a very specific water temperature, 45[degrees]F (7.
The major flow distribution being captured using the hydraulic model is related to the variations in computer room air handler (CRAH
) operation to predict the water flow rate to each CRAH
and subsequently calculate heat removal in each device.
Yet until now, data center managers have not had an accurate way to measure and manage the performance of CRAC (computer room air conditioning) and CRAH
(computer room air handling) cooling units.
1k applies to HVAC equipment intended for computer rooms as rated by Standard-127--typical CRAC & CRAH
HVAC equipment only.
Kennedy explained that Raging Wire's current project for controls modifications of its computer room air conditioning (CRAC)--including controlling supply air temperatures and dynamic static pressure control with SynapSense and variable frequency drives--will conservatively save more than $2,000 per CRAH
with a 20 percent reduction in static pressure.
With traditional entering water temperatures to the CRAH
unit of 45[degrees]F, 100% "free cooling" can be achieved with fluid economizers, when the ambient wet-bulb is approximately 35[degrees]F.