On Sun, 5 Nov 2000 13:37:09 -0800, you wrote:
>Does anyone have a copy of the EIA-310 document? (For the uninitiated, EIA
>is the Electronic Industries Alliance, formerly the Electronic Industries
>Association.)
>
>EIA-310 carries the title," RACKS, PANELS AND ASSOCIATED EQUIPMENT."
>
>According to a summary of this document in the EIA 1991 Catalog, it
>incorporates metric measurements. However, every manufacturer of
>rack-mountable equipment in this country specifies that their products fit
>19" standard racks (or other less common sizes). The standard they refer to
>is allegedly a RETMA one. However, RETMA became EIA 43 years ago, so I
>always take a RETMA standard rack reference as an EIA-310 reference. (RETMA
>stands for Radio Electronics Television Manufacturers Association.)
>
>If anyone has a copy, could you please say whether it specifies 19" or 480
>mm.
>
>Also, a vertical module in a rack may be specified as being 1-3/4" deep.
>Again, is this really 1.75" or is it 44 mm (or 45 mm)?
Bill:
I don't claim to have all the details, but I can say that the 19" rack
is still alive and well here in the UK. Many of our customers in the
military have been using these for many years, so we still have to do
development around them. In practice, of course, the design of the
equipment mounting to fit into the racks is done in millimetres. As
for vertical heights, they are done using the 'U' unit, which, I
believe, is 45 mm.
It's been a while since I looked into this, but I believe that there
is a hard-metric replacement for the 19" rack.
Chris
--
Metrication information: http://www.metric.org.uk/
UK legislation, EC Directives, Trading Standards links and more
Pro-metric mailing list now available.
