TechTalk

Rack Cooling

Welcome to Tech Talk, Pico Macom's series of technical notes, featuring useful information and equipment tips. This installment of Tech Talk discusses using Pico Macom's shelving and cooling system to cool equipment operation and provide optimum performance.

Is it Getting Hot in Here?

Summer is almost here. Have you taken a look lately at the operating temperature of the equipment in your headend? Years ago, we would place one of the probes of a dual-probe thermometer outside the rack at room temperature. The other probe would be inside the rack, taped to the top (or second to top) piece of equipment near the power supply. This allowed us a view into the environment that the equipment had to operate. Many times it wasn't a pretty sight.

Let's face it: Equipment is rarely placed in a room where 1) forced-air cooling comes up from the floor and through an enclosed rack and 2) the "in rack" temperature is lower than the ambient room temperature. Many times the television system is an afterthought, and equipment cooling is not a thought at all. I have placed equipment on shelves over sinks in utility closets, where it made the most sense for signal flow.

The three things that are damaging to electronics equipment are: heat, moisture and dust. In this Tech Talk we will address heat and dust. At Pico Macom, our staff designs and builds headends for a variety of applications and environments. Our highly trained staff can assist you with the selection of our high quality products to suit your every need.

Cool it Down

There are ways we can plan cooling into the system before ever getting to the overheating stage. The proper planning and placement of equipment in the headend will allow the system to operate trouble-free for years with only minor routine balancing.

Equipment Spacing

Rack Mount. Often a common mistake is made during the headend design stage when we ask, "How many pieces of equipment will fit in a rack?" The correct answer is: "As many as it takes to fill a rack of that size while leaving at least one blank space between each piece of equipment." Ideally, we place like pieces of equipment in the same rack. The downside to this is that each piece has a power supply located in the same general area. The heat from the bottom unit in the rack will be partially absorbed into the next unit up. This heat transfer adds to each unit in the rack until reaching the top piece of equipment. Leaving at least one empty rack space will greatly reduce the amount of heat transferred.

Non-Rack Mount. Many products used in the headend system are simply not designed for rack mount applications. These can be consumer satellite receivers or security equipment. As mentioned above, like equipment means like power supply placement. We are faced with another problem when the equipment isn't designed with mounting ears for rack mounting. How do we space them apart? A single shelf (MOR-S) is great when you have a single unit to mount, but what about a cherry-picking scenario with an existing CATV or satellite lineup where there are 48 receivers being used? Single shelves are not the most practical. Multi-position vertical shelves (MOR-S6, MOR-S8) are the best option. For best results, place the equipment in the shelf so that the power supplies are positioned at the top and leave at least one rack space between shelves for ventilation.

MOR-CS Placement

Rack mount cooling system: Forcing air across a heated area assists with cooler operation, like blowing across a bowl of hot soup. It is a good practice to remove hot air from the rack whenever possible. A cooling system such as Pico Macom's MOR-CS provides three large air channels that pull the hot air from inside the rack through the intake vents located on the bottom and expel it out the front of the unit. In an enclosed rack with forced air application, these units are placed at the top to pull the cooler air up through the rack faster, increasing the natural air flow velocity and cooling the equipment more efficiently. In open side rack and/or non-forced air applications, the fans should be placed at mid-level and at top to remove the heat buildup before it becomes detrimental to the equipment in the racks. In addition to the cooling properties, forcing the air through the equipment ensures that dust particles don't settle on circuit components, which further causes heat buildup. Additional cooling systems should be placed on top of congested areas such as Mini-Chassis systems and MOR-series vertical equipment shelves.

Using Pico Macom racking and cooling products is a snap!

Want To Know More?

Click on the links below to learn more:

MOR Rack System

Click Here for all MOR Series Equipment Rack

The products mentioned above make system racking and cooling easy and efficient. These are just some of the many innovative products available from Pico Macom.