Hi, How much air the PSU fan moves has absolutely no impact on switch cooling, it's only cooling the PSU (at least on 3200, haven't pulled a 4200 apart yet). Also take into account that the fan assembly is moving a larger volume at a lower speed, so a measurement with a piece of paper wouldn't necessarily give you the right impression. --- Martin Levin IT-strategy & planning Mölndals stad
>>> Från:Bjørn Skovlund<[email protected]> Till:Bill Blackford <[email protected]> Kopia:"[email protected]" <[email protected]> Datum:2010-11-03 10:40 Ärende:Re: [j-nsp] EX4200 Air Flow Hi Bill, We have around 80 EX-3200 (24 port RJ-45, with SFP module) and 30 EX-4200 (24 port SFP, with XFP module) in production. They're all located at telco pops, an environment with cooling, but not from the floor and also quite densely populated locations. Not ideal environment, so to say. I've run some quick stats and on the CPU, the temperature is of the same average. On the PFEs, the 4200s are in avarage 5 degrees celcius warmer than the 3200s. If it's possible to make any conclussions about airflow from this, I'm not so sure. As you can guess with the uplink modules, our 4200s are running a much higher packet-load than our 3200s. We've not found any problems with heating so far - and most of our EXs have been running for around 10 months now. Cheers, Bjørn On Tue, Nov 2, 2010 at 9:22 PM, Bill Blackford <[email protected]> wrote: > I have several EX3200's and EX4200's installed in my Data Center. In comparing the two, they both intake from the sides and exhaust out the back. Actually, the EX3200 has intakes on both sides, the EX4200 only on one side. Using a very low-tech method for measuring air flow (my hand and a small strip of paper), it really seems like the EX3200 has better air flow than it's big brother. The removable fan assembly on the 4200 is barely moving any air. The Power supply fan on the 4200 has higher air flow, but the overall flow seems to be much less than the 3200. > > Has anyone experienced heat issues with these? > > Thanks, > > -b > > -- > Bill Blackford > Senior Network Engineer > Technology Systems Group > Northwest Regional ESD > > Logged into reality and abusing my sudo priviledges > > > _______________________________________________ > juniper-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/juniper-nsp > _______________________________________________ juniper-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/juniper-nsp _______________________________________________ juniper-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/juniper-nsp

