TIA 41.7 and Underwriters Laboratories are interested in obtaining
information and input relating to concerns, complaints and problems with the
cutover from UL 1459 to UL 1950 3rd Edition for equipment designed to be
owned, installed and maintained by a telecommunications provider. This is
equipment and installations that are traditionally exempt from the NEC, but
could make up the demarcation point. The cutover is scheduled for March
15th, 2000.
Interest in telco providers having "safety listings" on new products they
purchase has grown rapidly in the last few years. Equipment installed by
the telco providers has traditionally been built utilizing design guidelines
based on Bellcore standards (such as GR-1089-CORE), and/or UL 1459. As many
of you know, UL 1950 3rd edition is based upon spacings called creepage and
clearance. Traditional telco installations are deficient with regard to
creepage and clearance, but will meet the dielectric tests called out in UL
1459. There are also substantial differences between GR-1089-CORE, UL 1459
and UL 1950 3rd with regard to voltage limits.
In discussions with various telco providers over the past month, there has
been a consensus that there is not a perception of safety problems and there
is some concern that the ramifications of eliminating UL 1459 could have an
undesired impact. They have stressed that harmonization is not a factor as
the infrastructure used in North America is unique. They also stressed that
they have 3 basic concerns with regard to safety listings; no increased cost
to the product, can utilize existing shelves, housing, channel banks and
infrastructure, the listing is to a standard that is acceptable into to
foreseeable future. UL 1950 3rd Edition without some substantial deviations
will not meet the needs of the telco providers.
Work is currently ongoing at UL to determine if UL 1459 needs to be revived
for network equipment, reissued under a new standard number with a revised
scope for network equipment only, or develop deviations in UL 1950 3rd
edition.
As such, if you have any input, concerns or issues with the above mentioned
topic, TIA 41.7.1 and UL would be very interested in your comments. They
are trying to determine if there is industry support to look further into
these issues. Please forward this E-mail to anybody you know that might be
outside this mailing list that also might be interested.
Please send comments, complaints, problems etc. to:
1.) Randy Ivans (chairman of TIA 41.7.1)
iva...@ul.com
516-271-6200 ext. 22269
2.) Mark Vlanich (UL Engineering Team Leader)
vlani...@ul.com
919-549-1647
3.) Jim Brunssen (Telcordia formerly Bellcore)
jbrun...@notes.cc.bellcore.com
973-829-2977
4.) Or simply respond to me and I will present it to TIA in May
Thanks,
Jim
Jim Wiese
Compliance Engineer
ADTRAN, INC.
901 Explorer Blvd.
P.O. Box 140000
Huntsville, AL 35814-4000
256-963-8431
256-963-8250 fax
jim.wi...@adtran.com
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