AMAZING!!! For years, I have blown off the UL categories as some form of lingo that only UL understands. Of course I'm not so sure that this is still not the case. I've never heard a customer ask if I'm listed to "DUZO" or "NWGQ" or "WYQQ". Are these categories used by CSA, ITS, CCL and other NRTL's or is this just a UL thing. Does Canada accept these listings to "DUZO". The NRTL's that I am dealing with typically require a listing to UL-1459 or UL 1950 in order to meet Requirement R4-5 of Bellcore GR-1089-CORE. In addition, note 10 of section 4.5.13 of GR-1089-CORE specifically calls out a listing to UL-1459 and the ILR allows UL 1950 if the construction method for overvoltage is not used. Should they be calling out "DUZO" etc. Please pardon my ignorance.
Jim James Wiese Regulatory Compliance Engineer ADTRAN, Inc. 205-963-8431 205-963-8250 FAX [email protected] >---------- >From: Randolph Ivans[SMTP:[email protected]] >Sent: Wednesday, January 28, 1998 8:48 AM >To: [email protected] >Cc: Thomas Lanzisero; Vincent Sylvester >Subject: RE: telco spacing, listings, etc. > >Jim, > >You are correct that if a product is being evaluated to a standard, then in >order to say it complies with the standard it must comply with the whole >thing.The key here is that you don't necessarily List a product to a >standard, you List it under a category. There is a difference between a >standard and a category. Often the two are completely integrated and >inseparable but not always. > >UL's category for ITE (NWGQ) is directly linked to UL1950. Therefore, a >Listing to NWGQ automatically says that the unit complies with UL1950 (all >of it!). The same was true for the Telephone Equipment Category (WYQQ) >which indicated compliance with UL1459. This has changed now since under >the Telephone Equipment Category a product can now comply with either >UL1459 or UL1950. So here the category no longer is tied to only one >standard and Listing under WYQQ indicates compliance with either UL1950 3rd >edition or Ul1459. > >In UL's "Custom-Built Telecom Equipment" category (WYKM) for service >provider installed modular equipment, additional requirements, over and >above UL1459 or UL1950, are added to take into account the modular, field >installed nature of the equipment this category covers. So here, Listing >under this category indicates compliance with a set of requirements that >goes beyond just UL1950 or UL1459. > >Another good example is our category for "Static Neutralizing Equipment" >(VWWZ). This category now uses UL1950 for its basic requirements but also >references UL867 (Electrostatic Air Cleaners) for some high voltage >requirements. In this example, the resulting evaluation again exceeds the >requirements in UL1950. However, this does not necessarily have to be the >case. > >The Communication Service Equipment Category (DUZO) covers equipment that >is similar to other telecom equipment but is installed by highly trained >personnel in a harsher environment (often on the unprotected side of the NI >or actually is the NI). It seemed natural, therefore to start with the >telecom equipment standards when looking for requirements so UL1459 or >Ul1950 are used. To deal with the harsh environment issues, additional >requirements are added from various other standards better suited to deal >with these issues. However, since the level of training of the installer >amd maintainer is usually high, some requirements are relaxed in the area >of markings, instructions and what is allowed to be covered in installation >practices. So here it is possible that a unit may not meet all of the >clauses of UL1950 or UL1459 in some areas but will probably exceed the >UL1950 or UL1459 requirements in others. > >To deal with specific equipment issues like the type of equipment, >installation criteria, etc., a category can call on one or several >standards or a new standard can be written. A recent trend is for new >requirements, or even a new standard, to call on an existing standard (like >UL1950) then add or subtract requirements as necessary. This is being done >in the area of DC Distribution Equipment for Telecommunications Equipment, >UL Subject 1801. > >As an example, a standard can be written that states: >"1. Equipment shall comply with UL1950.". >"2. Exception: Spacings in telecommunications circuits may be judged on >the basis of the dielectric voltage-withstand test in >UL1459." >Of course a product Listed under a category that uses this mythical new >standard could not be claimed to comply with UL1950 but this would be made >clear in the category description. Actually, it would have to be made very >clear so there would be no chance of mis-representation of what a product >complies (or doesn't comply) with. > >There would have to be an expressed interest or need to develop such a >category or standard but it would not be too difficult to do so.As I >mentioned before, I brought up the idea of possibly maintaining UL1459 for >specialized domestic equipment (where there was no need to go to >international requirements) a long time ago at the TIA TR41.7 meetings but >there was no interest expressed. If you want to discuss this further, >please give me a call at (516) 271-6200 X22269 > > >Randy Ivans >Business Sector Coordinator >Telecommunications Industry >email: [email protected] > >
