All: I have received a copy of a CENELEC Decision (dated 6/98) regarding the use of varistors between mains conductors and ground. This particular Decision is written in a rather unclear fashion (at least its unclear to me...I tend to be rather literal in my interpretations of written requirements), and I am struggling with defining the actual requirements.
If anyone out there has received this Decision, and believes they are clear about what the actual bottom line requirements are, please let me know. I have muddled through some of the issues, but need some confirmation on a couple of points (see the questions below). It may seem to some that the answers to these questions are straight-forward in the Decision, but I have studied this Decision (maybe too much) and find these points unclear. 1) Is this Decision only for pluggable equipment type A, or is the spark-gap / fuse requirement in effect for pluggable equipment type B as well? 2) Will Denmark, UK, and Sweden accept varistors to ground if the circuit contains a spark-gap and two fuses? 3) The installation instructions for our PABX systems include the requirement for a permanently connected ground wire between the equipment ground and an approved building ground (this ground wire is in addition to the "green wire" lead in the AC mains). This wire is required for all our PABX systems (AC and DC powered systems, pluggable type A, type B, and permanently connected systems). Does this permanent ground connection provide an exemption to this Decision? If this Decision means DK, UK, SE will simply not accept varistors to ground, then a lot of small pluggable type A equipment intended for sale in DK, UK, SE will have to either: 1) discontinue using varistors, or 2) become pluggable equipment type B (which would be onerous, given the IEC 309 plugs I've seen). Thanks for the help. John Boucher jpbouc...@lucent.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).
