Thermal Management in Cabinets

There is no one thermal management configuration that works best in every instance. Each may be optimal, depending on different factors unique to the customer, application, and environment.

Consideration  should  be  given  to  understanding  the  upfront  installed  costs  as  well  as  an ongoing operational cost from an energy efficiency and maintenance perspective.

Equipment should be installed in cabinets with the air intake oriented toward the front of the cabinet or rack and the air exhaust oriented toward the rear of the cabinet or rack, when possible, with the cabinet rows oriented in a “hot aisle/cold aisle” configuration—rears of cabinets facing each other and fronts of cabinets facing each other.

Use of any supplementary cooling mechanisms on a cabinet must take into consideration its effect on the overall fluid dynamics of the air space and how other equipment will be affected.

Considerations of supplemental cooling systems need to include criticality and required levels of redundant backup.

Cabinets with good passive air management systems in well-designed rooms remove concerns about single points of failure and can support heat loads of twenty kW and higher.

Cabinet fans for cabinets specially designed to handle high heat loads should be on UPS power and have redundant power cords or be on transfer switches to ensure continuous operation.

Cabinet fans should be on separate circuits from the equipment in the cabinet as fans are susceptible to ground faults.

The perimeter of the equipment mounting area is also a path for cold air bypass or hot air recirculation and should be blocked accordingly.

Careful planning is needed for capacities, heat loads, and redundancies required for the desired availability and reliability.