How do x450e switches behave when overheating? Do they safely power-down?

[Brian_Mankin]

Hello all,

We have a set of stacked switches running in a poorly cooled, poorly ventilated area. The warmest switch runs at ~60°C. The cut-off temperature is 67°C. A few days ago, the switch overheated while IT was closed and some users lost their network access.

I have been asked if this is a health and safety issue. I'm trying to find out what how the x450e switch behaves when it overheats. Will the switch keep trying to run, potentially getting hotter and hotter until the atmosphere ignites and we all die in a horrible fireball, or does a sensibly-installed thermal fuse disconnect power, saving the world from an otherwise certain doom? Personally, I'm hoping it's the latter.

Thanks in advance.

Brian.

[Steve_Ballantyn]

I can't speak of Extreme products. I am only a potential customer at this point. But I have had this same problem with heat. In my case it was a short stack of Cisco switches in a wiring closet that was getting way too hot. Not as hot as your stuff though. Holy cow. I had to do the math on this one being a yankee. That's over 150 degrees F.

My wiring closet was air-tight by design. Overhead of the room was a drop ceiling, and all the tiles were glued in place with this nasty sticky red stuff know as "fire calk". The door is a two and a half inch thick, solid wood monster. They refer to those as "a two hour door". Meaning that if a fire gets going in there, it will literally take two hours to burn through that door. That's plenty of time for everyone to regret the decision not to act on that hot room.

I asked for a vent in the door - but that defeats the point of the fire door. But because the particular drop ceiling was *not* a return, it was legal to put a vent into the ceiling. Not a fan. Nothing fancy. Basically just a big hole, with a nice vent look to it.

But giving that room a place for the heat to go dropped the temperature almost 20 degrees for me. It may not be a permanent solution to your problem, but it should get you out of the meltdown range. And we are talking about 10 minutes of work and a $15 part. Although - if your drop ceiling acts as a big return vent (plenum), this is probably not an option for you due to fire code.

[Frank]

I apologize, but I can't hold back anymore! 🙂

I do not have the answer regarding the existence of a thermal fuse
(outside of: at some temperature the chassis will melt and likely short the power cord, which should trip the office's breaker. Prior to this, fire suppression systems might go off, and if they're water based could also trigger shorts and the breakers might trip before chassis meltdown)

Reddit appears to have a decent discussion about igniting the atmosphere with various theories about the heat needed (depending on certain circumstances):
https://www.reddit.com/r/askscience/comments/1plizv/what_temperature_would_be_required_to_ignite_the...