Avaya 3510GT-PWR+

[edwar128]

I have 4 Avaya 3510GT-PWR+ switches, I have them all in fanless mode and a few of them are mounted to drywall. When the switches are in fanless mode they become really hot even though I am not using any PoE devices. I may sound a little crazy but is there any possibility that the switches could start a fire due to the heat. They are in areas with decent airflow but I am not a thermal engineer.

All comments would be beneficial, Thanks.

[jburba]

Same here. In EDM, I was monitoring the temperature and it was reaching 54C which is above its posted operating temperature range of 0-50C. I disabled POE and shutdown all ports that were not being used and those that were, 3 of them at the moment, I was using in 802.3af mode. I have it mounted on dry wall, with a good distance to any walls and the fan unobstructed, but it was getting hotter than I was comfortable with. The unit is mounted in a closet, without AC, but more than adequate ventilation. With the fan on, high-power mode, it drops it to 35C. I'm guessing they are meant to be run with the fan on, if not kept in a cooled network closet.

As some clarification, I work in IT, and I use the 8 port POE+ switch at home with some network security cams and some access points. My employer uses the 48 port ones in stacks so I am familiar with them, but the 48 port ones are always run fan on or in a cooled server room. I never bothered to see what the requirements for cooling was for the devices before hand. Unless the sound is distruptive, just run it in fan mode, it is not silent, but it is whisper quiet.

That said, can anyone chime in as to what settings are best to reduce energy use (ie less heat production)?

[zakabog]

The switch will fail well before it gets hot enough to start a fire, the ignition temperature of paper is around 220C. The switches CPU running with no fans is what's causing the temperature to spike. Is there any reason you have it running in fanless mode in an environment that isn't temperature controlled?

[jburba]

I have been tinkering with mine. CPU pretty much does cpu things, so I disabled all remote access save ssh. I also made alterations, at my own risk, to the chassis, namely drilling holes and creating a pretty nice design on it. That said I ran it without the chassis cover for some bit. Most of the heat production is not even coming from the CPU, but the built-in power brick. This is why no matter how little devices you connect to POE, it starts hot, as just being on, produces heat for the brick. This is why without the chassis cover, it ran at most at 43C with 4 POE devices connected and no fan on. With the chassis on, it keeps the heat in and the fan is positioned right where the brick is, so it is meant to pull hot air from there not the cpu, because again the CPU is fine. With the fan off, the heat from the brick, the boxed in chassis makes it a convection oven. I'm drilling more holes into my cover for both air circulation and added surface area. Since it is aluminum, it will help dissipate heat better if I sand off the paint and expose the aluminum. Again this is just me, taking my own risks, with my own devices, but you can use what I learned as you wish. From this, my conclusion is that this device is not meant to run fanless, thought the option is nice, in room temperature closet, or area. In a temperature controlled server room, like at my job, it'll be fine, but from the small size of the fan, the savings will be just pittance.