Data centers that house servers and other computer equipment crucial to the success of many companies require a specialized controlled environment to function properly. These areas must be maintained at a consistent temperature to keep the equipment running at peak efficiency to help reduce energy costs and must keep out dust and contaminants to prevent premature equipment failure.
The wrong pressure instruments can result in inaccurate measurements, damage to equipment and downtime for your application.
Differential pressure sensors are used in several different applications in data centers. This article will discuss these applications and what product features make for the best differential sensors for these applications to ensure applications run accurately and efficiently.
Proper Temperature for Peak Performance
Maintaining the proper temperature in a data center is critical to its overall efficiency. The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) recommends the temperature in a server room or hallway should be maintained between 60 F to 80 F for maximum efficiency. If the temperature is too high, users run the risk of hardware or system failure. If the temperature is too low, the energy cost of the data center increases.
In a raised floor, open-air data center, where data floors are broken into zones, differential pressure sensors can be used to monitor and control the under-floor pressures which are used to increase or decrease the computer room air control (CRAC) or computer room air handling (CRAH) fan speeds to help maintain proper airflow and temperature control. In data halls with hot/cold isle containment, airflow control and proper pressurization is critical to maintain cooling air to rack mounted servers and equipment. By precisely controlling rack inlet pressures, adequate cooling is ensured to prevent equipment damage or premature failure.
In addition to helping run servers at maximum efficiency, another benefit of tightly controlling the temperature in the server room is it provides a cost reduction in the energy use of the data center. The closer the room can be kept to the high end of the recommended temperature range, the less energy will be required to heat or cool the room. Ultimately, this leads to a reduction in energy costs.
To prevent dust and other contaminants from entering the room where servers are stored, many data centers use heating, ventilation and air conditioning (HVAC) systems designed to create a positive air flow in the room so when the door to the room is open, the air flows from the room out into the hallway. This prevents any dust or stray contaminants from entering the room, keeping the servers in pristine condition. This type of positive room pressure is often found in cleanroom applications and uses a differential pressure sensor to monitor the pressure differential between the room and the hallway to make sure the air is flowing in the right direction.
Sensor Reliability & Repeatability
All the applications listed above require a differential pressure sensor that is accurate, repeatable, reliable and stable enough to help control the HVAC systems. Since the goal is always to keep the system operating at peak efficiency with limited downtime, the pressure measurement instruments must be designed with a reliable sensor technology that can measure the slightest difference in pressure while continuing to operate accurately, reliably and efficiently over time. The energy savings assumed to be gained by tightly controlling the temperature can be affected by the accuracy of the differential sensor. If at any point the accuracy of the sensor shifts from +/- 0.25% to +/- 1.0% or more, users lose the tight control of the process and start to escalate energy costs. Having a repeatable pressure sensor with minimal long-term drift will also help to reduce the downtime needed for periodic calibration and verification, allowing the systems to run longer with greater efficiency.
Now that users better understand the pressure instrumentation requirements for HVAC systems in data centers, they can research the solution that is best for airflow measurements. Keeping these factors in mind can help ensure problems are avoided and keep applications running with reliable and accurate pressure measurements.