Path: ...!weretis.net!feeder9.news.weretis.net!news.quux.org!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail
From: John R Walliker <jrwalliker@gmail.com>
Newsgroups: sci.electronics.design
Subject: Re: Experiences with rack mounted kit mounted *vertically*
Date: Wed, 5 Feb 2025 18:21:09 +0000
Organization: A noiseless patient Spider
Lines: 40
Message-ID: <vo0a6l$2f81e$1@dont-email.me>
References: <vnvlhf$2ckn5$1@dont-email.me>
 <1r7afie.5wsq3lp0d9hcN%liz@poppyrecords.invalid.invalid>
 <vo03m6$2eunq$2@dont-email.me>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Date: Wed, 05 Feb 2025 19:21:09 +0100 (CET)
Injection-Info: dont-email.me; posting-host="537923f7f9730483fdb3d13fd1613d83";
	logging-data="2596910"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX1+zGf6Ln+7kAFhWuC7WHJaI+NjN9gqnQtE="
User-Agent: Mozilla Thunderbird
Cancel-Lock: sha1:1yg3rRjxLHEDkJG7HwIAlS7Lamg=
Content-Language: en-GB
In-Reply-To: <vo03m6$2eunq$2@dont-email.me>
Bytes: 2939

On 05/02/2025 16:29, Don Y wrote:
> On 2/5/2025 8:16 AM, Liz Tuddenham wrote:
>> Don Y <blockedofcourse@foo.invalid> wrote:
>>
>>> Anyone have any long-term experiences regarding (wall) mounting
>>> rack mountable kit front-down or front-up?  Reliability,
>>> accessibility, etc.  And, any suggestions to protect the
>>> openings-susceptible-to-gravitational-interference?
>>>
>>> Any suggestions as to which (-up or -down) might be better?
>>>
>>> For a start, I'd like to mount six 48/52-port switches.
>>> Most of the mounting kits suggest this is within their
>>> typical weight limits.  But, 4U seems to be the most common
>>> arrangement (I'd like to have to avoid using two kits)
>>
>> If your kit contains any relays, make sure they will be mounted so that
>> the contact gap is in the vertical plane.  That allows dirt to drop out,
>> rather than being retained and ground into the contact faces.
> 
> The (*these*) switches don't have any relays (AFAICT).  But, I
> will have to consider that for some of the mains-related
> switching.
> 
> Thanks!
> 
Some fanless 24-port network switches from HP specify that they can
be mounted with the connectors up or down but not sideways.
Sideways mounting would give the best airflow, so there must be some
other explanation.  My best guess is that the relatively large
"side" ventilation holes would not allow the product to pass regulatory
safety testing in that orientation.  (Holes must be small enough that
burning molten plastic cannot fall through the holes and ignite
flammable materials below.  Similarly, holes in the top must prevent
flames from escaping and they must protect against foreign objects from
dropping in and causing damage.

John