Thanks Tania for the response. I believe your response shows that there is a need to open dialogue to work out these issues. I will attempt to answer your questions.
1.) In North America (including Canada) the telco providers traditionally have purchased equipment designed around Bellcore GR-1089-CORE which from a practical standpoint allows up to Class A3 voltages to be present throughout the network. Class A3 can be met with voltages up to +- 200 VDC as long as current to ground is kept under 5 mA. The telco providers also have continuous (non-ring tripped) 120V 20 to 63 Hz ring generators connected to most channel banks for POTS service This is a Class B voltage. None of this falls under any TNV category in section 6 of UL 1950 which limits TNV voltages to +- 60 VDC plus "tripped ringing" and message waiting. At best, some of this network equipment is already listed to UL 1459 and can (and will be purchased until 2005). Much of it will be in service for 30 years or more. The only design criteria with regard to insulation in Bellcore standards or UL 1459 is a hi-pots test. Creepage and clearance do not exist in traditional C.O. equipment (just look at wire wrapped backplanes). With the voltages stated above running around everywhere, reinforced or double insulation at 200 VDC (4.0mm) and basic insulation (2.0mm) would be needed on equipment shelf and channel bank backplanes, as well as punchdown blocks, "champ connectors", wire wrap installations, protector modules etc. As new technologies are developed, the old channel banks, equipment shelves and so on are not removed. New circuit cards are developed to go into these existing pieces of equipment. Examples are T200/T400 shelves and housings, AT&T/Pulsecom/ADTRAN D4, SLC 2000, D5, DDM+, Siemens, Nortel, Alcatel, Litespan channel banks (on and on). If Listed, these new cards are listed to UL 1459 as they cannot meet the creepage requirements of UL 1950. Creepage/Clearance (spacing) deficiencies exist on the backplanes, channel card edge connectors, wire wraps and the "champ" connectors. All this stuff would have to be scrapped under UL 1950 which would cost telco providers hundreds of millions or billions of dollars. That is why UL 1950 being the only safety standard listing option (as of March 15th 2000) is not good for the telco providers. Although it would be great for us manufacturers because we could sell them all new equipment. 2.) I agree fully that if a new product can meet UL 1950 you should have that option. However there are technologies utilized by the phone companies that generate ringing to POTS lines or that provide powering to remote network equipment that simply violate UL 1950. The phone companies in North America must power remote equipment over the telco span (up to +- 200 VDC) as the commercial AC is not reliable enough to meet the minimum down time requirements set by the FCC Tariffs. It also allows you to call 911 when lightning catches your house on fire and knocks out the AC power. 3.) This entire issue is not a problem for international products as the ETSI and IEC standards mesh very well and they do not have FCC tariffs. IEC 950, EN 60950 etc., also allow up to 120 VDC as a TNV 3 voltage. In the U.S and Canada, the Bellcore and UL standards do not mesh (200 VDC vs. 60 VDC). 4.) Lastly, most network equipment actually falls outside the scope of UL 1950 3rd Edition. UL 1950 Scope: "This standard is applicable to mains-powered or battery-powered information technology equipment, including business equipment and associated equipment, with a rated voltage not exceeding 600V and designed to be installed in accordance with the Canadian Electrical Code, Part1, CSA C22.1; CSA C22.2 No. 0; and the National Electrical Code, NFPA 70." "This standard is also applicable to such equipment designed and intended to be connected directly TO a telecommunications network and forming part of a subscribers installation, regardless of ownership and of responsibility for installation and maintenance, and regardless of the source of power." a.) Network equipment is exempt by the National Electric Code on the telco providers side of the demarcation point (except in Canada where ownership comes into play). Most telco providers insist that equipment installed at the customer premise be designed to meet the NEC and be listed, as such the wiring means on the customer side of the demarc point meets the NEC and the telco side of the demarc has no NEC requirements as it is exempt. This is a good thing, otherwise the phone companies had better hire alot of licensed electricians and run alot of conduit. Of course an electrical inspector would have to certify the installation prior to phone service being turned on. b.) Just like with FCC Part 68, network equipment does not connect to the network and make up the subscribers installation, network equipment IS the network and makes up the TELCO PROVIDERS installation (not the subscribers) and is exempt. In short, there is no UL safety standard that covers network equipment at this time. Although some newer types network equipment might be capable of being Listed to UL 1950. 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 > ---------- > From: Grant, Tania (Tania)[SMTP:tgr...@lucent.com] > Sent: Tuesday, March 23, 1999 10:32 PM > To: emc-pstc; 'TREG'; NEBS FORUM; 'JIM WIESE' > Cc: Ron Bernot; Randy Ivans; Mark Vlanich; Jim Brunssen; Tom Burke; > Kevin Ravo; 'MARK WALKER'; Bob Burek; Tom_Amatulli; Frank Terlato; Bob > Raskey; harry.vanza...@telops.gte.com; chuck_gr...@smtp.nynex.com; > tto...@uswest.com; jmla...@uswest.com; mben...@uswest.com; > sbi...@hotmail.com; Larry Todd; Keith Kuhn > Subject: RE: Network Equipment and UL 1459/1950 > > Jim, > > Thank you for giving us an opportunity to respond. > > It would have been very helpful if the telco providers referenced in your > e-mail were more specific as to why they cannot "harmonize" with UL1950 > requirements. By specific, I mean paragraph by paragraph. But let me > guess > from the few statements that you have made. They cite cost and the added > requirement of measuring creepage and clearance rather than just > performing > the dielectric strength tests. I have a response to that. > > The telco providers to the public are no longer providing the hardware; > they > are purchasing it from other hardware companies that are not providing > telco > connections to the public. These hardware providers are providing > equipment > to world-wide customers. These customers are requiring IEC950 derivative > standards. Those of us selling internationally are designing and meeting > UL1950/IEC950 requirements. To us, the increased cost to design to two > different standards and/or to submit equipment twice for testing to two > different standards is an undue and unnecessary burden. Whose cost is > greater, can be debated, but I don't think that would resolve anything. I > think, however, that it should be stated that in either case, there is > cost > involved to both parties. > > Thus, we are adamantly opposed to UL's proposal (your 4th paragraph) that > UL1459 be "revived" for network equipment only. UL should realize that > the > traditional "telco providers" are not at the forefront of industry > technology;-- the future is sophisticated PC applications and servers > interconnecting the world utilizing voice, Internet, Ethernet, and fast > data > links. This is indeed "information technology equipment", whether it be > located in a central office telephone switch room or in a hospital, bank, > or > university. The location no longer should matter;-- safety of the > equipment does matter. And safety should not be relative to geography > (humidity excepted!) > > To alleviate the burden of increased costs for those few hardware > providers > who are not selling to the international market, I offer the following > recommendations: > > * Extend or retain UL1459 for the domestic U.S. market only, provided > the UL1950/IEC950 harmonized requirements remain an option to those of us > who wish to ship internationally. It should be noted that Canada (unless > they change their minds dramatically) has harmonized with IEC950 earlier > than UL and, I don't believe, would consider going back to C22.2, No.220. > > or > > * Add another Appendix to UL1950, similar to NAE, that would list > UL1459 only options in lieu of the stated UL1950/IEC950 requirements. > During UL product evaluation, a statement could be added under Engineering > Considerations that this product meets only U.S. requirements. Under > those > circumstances, obviously, UL would never consider providing a CB Scheme > Report and Certificate. The rest of us will happily take UL1950 and the > CB > Scheme Report. > > I believe that by considering either of the above two options, UL can make > both parties happy. But please, do not "revive" UL1459 for telephone > equipment and punish the rest of us. > > Tania Grant, Lucent Technologies, Octel Messaging Division > tgr...@lucent.com > > > ---------- > > From: JIM WIESE[SMTP:jim.wi...@adtran.com] > > Reply To: JIM WIESE > > Sent: Monday, March 22, 1999 4:06 PM > > To: emc-pstc; 'TREG'; NEBS FORUM > > Cc: Ron Bernot; Randy Ivans; Mark Vlanich; Jim Brunssen; Tom > Burke; > > Kevin Ravo; 'MARK WALKER'; Bob Burek; Tom_Amatulli; Frank Terlato; Bob > > Raskey; harry.vanza...@telops.gte.com; chuck_gr...@smtp.nynex.com; > > tto...@uswest.com; jmla...@uswest.com; mben...@uswest.com; > > sbi...@hotmail.com; Larry Todd; Keith Kuhn > > Subject: Network Equipment and UL 1459/1950 > > > > 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 > > > > --------- > > This message is coming from the emc-pstc discussion list. > > To cancel your subscription, send mail to majord...@ieee.org > > with the single line: "unsubscribe emc-pstc" (without the > > quotes). For help, send mail to ed.pr...@cubic.com, > > j...@gwmail.monarch.com, ri...@sdd.hp.com, or > > roger.volgst...@compaq.com (the list administrators). > > > --------- This message is coming from the emc-pstc discussion list. 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