Keeping 5-slot carrier cool

[jlshelton]

Based on some of the warnings here, it sounds as if heat may be the number one killer of Partner parts. To avoid problems, I've tricked out the cover to my 5-slot carrier by adding some computer fans (80mm diameter, 12v, 50,000 hour life expectancy, $9.00 each) to the top of the carrier, helping exhaust warm air. Using a multi-voltage transformer from Radio Shack, I can adjust fan speed for a balance between good air flow and reasonable noise. 9v seems like a good compromise.

No need to drill holes or damage the cover: just wire-tie the fans to the top of the cover.

 

[telprog]

I just leave the cover off, that lets it run allot cooler.

 

[CinemaPhones]

Both solutions offer benefits while I tend to lean towards teleprog's suggestion... the new acs design does not include a top cover, with a simple backplane much like the older ones with the cover removed.

Otherwise, as long as your "fan-forced" switch is in a location where the fan operation can be monitored regularly as a by-product of simply walking by, etc, any heat removal is your friend.

My only concerns releated to strapping some fans on top is that regardless of their incredible life, they are subject to failure, and in their non-operational state, the extra frames and non-moving fins will only add to restricting heat.

The second concern is in pulling unclean air through. Using natural convective currents, most dust/lint/debris is too heavy to become pulled into the circuit packs. When you start to use fans to force airflow, be careful to make certain the air flow vents to not become blocked. If you've ever pulled apart a PC computer powersupply (or fan forced case) you'll see how heavily caked the components, grills and blades all become. The finer screens covering the heat vent openings may act like a plugged lint screen on a clothes dryer.

In short, I realize may of our end-users want to place KSU's into service in a variety of "harsh" environments including damp basements, attics, non-climate controlled closets and rooms, etc. Many of these customers are small system "old school" customers that often are replacing old switches 1A2, electro mechanical, and early electronics which didn't have microprocessors or hard drives. The mentality is often, "it was a good enough location for Ma Bell to install the old one."

Gently remind these end users that we're no longer talking about circuitry comparable to a garage door opener, but rather highly sensitive with all the electronics of that desktop computer. Demonstrate their own care of these desktop devices noting any surge protection, practices of unplug during lightning storms, cover at night when not in use, etc. They'll be a lot more receptive to your ideas regarding location including environmental and power conditioning suggestions.

 

[jlshelton]

In some 5-slot chassis, there is nothing to hold the cards in place other than friction. Experience teaches that eventually, boards will unseat themselves, particularly if there are power failures of > 10 minutes periodically. When I found this current system, the previous owner had used strapping material to keep the boards in place. Now, the cover does the job (I hope.)

Good points above from folks. Fans do need periodic inspection. Dust may become a problem. Normally, I prefer to see convective cooling used by itself, but clearly the Partner packaging is not as efficient, convectively, as some others.

 

[itpphoneguy]

Hi All,
The new 5 slot carrier has a top cover. You will notice that the cards are spaced further apart. Try to install these in the computer room or at least in an air conditioned area of the office. Life should be pretty good then.
-Chris