Chris, Clear away the ground plane to give you the proper clearance. You need to be able to pass the tests without an external protector. You didn't mention Part 68 in your message. You do need that as well, plus an FCC Registration Number (although what you have to do to file for it may be changing very soon), manual verbiage, etc.
If all else fails, you could supply a remote modem "switch" that would control power to your product. There are a few manufacturers but they can be a little pricey. Dave Spencer Oresis Communications -----Original Message----- From: Eric Petitpierre [mailto:[email protected]] Sent: Monday, May 22, 2000 10:14 AM To: [email protected]; Maxwell; Chris Subject: Re: Safety: Hi-Pot Suppression for TNV lines Chris, Usually the hi-pot tests done during the safety evaluation are meant to verify spacings and insulation. The hi-pot tests I have seen usually allow intentional paths to ground to be disconnected. It is the trace separation,etc, you are interested in, not how well the MOV conducts. Both MOV's are considered intentional paths to ground. Both should to be disconnected at the ground side during the test. If only one is disconnected, you may still have a path, whether it is direct, or through the contacts (open or closed) of the hookswitch. Eric Petitpierre Pulsecom Herndon, VA [email protected] ______________________________ Reply Separator _________________________________ Subject: Safety: Hi-Pot Suppression for TNV lines Author: [email protected] (Maxwell; Chris) at smtp List-Post: [email protected] Date: 5/22/00 10:33 AM Group, Is there an in-line adapter that we can install on a TNV line (in our case, a typical RJ12 phone line) to our product that will provide a second layer of hi-pot protection? The whole explanation follows for those who think they can help. Others can press delete right now and get on with their day. We produce a piece of fiber optic test equipment that is rack mounted and operates from 48VDC. Most of our typical equipment does not have TNV connections, however this does. We have designed a "remote reset" option. The remote reset consists of an RJ12 jack on the back of the unit. The user can plug a phone line into this jack. Once installed, the user can perform a 5 second power down on the unit by dialing the unit's "phone number" and letting the line ring 5 times. This has proved valuable to customers because the units are designed for remote installation. If the unit hangs up, they don't have to drive, fly, hike or swim out to where the unit is installed to perform a hard re-boot. This remote reset line only takes in the "TIP" and "RING" signals (the RJ12 only has pins 3 and 4 populated). Both TIP and RING have MOV's going to chassis ground. We have had the unit safety tested. During safety testing, the MOV's were cut (creating a single fault condition). When the MOV's were cut, the hipot test caused an arc to ground on a circuitboard within the unit. This arc was considered a failure. My guess is that the arc is caused by the fact that the tip and ring signals run close to a piece of the ground plane on the top layer of the board. My first stab at fixing this would be to clear out the ground plane so that it is furthur away from tip and ring. Now, even minor changes to circuitboards can cost thousands. It can also mean scrap. This unit is a very low volume product (hundreds annually). It may be more cost effective for us to add some sort of in-line suppressor external to the unit as opposed to revising the circuitboard. Given that the unit is rack mounted, I am assuming that there would be room in the rack to mount such a device, if it existed. Hence my question. Anybody have any ideas? Thank you for your time. Chris Maxwell, Design Engineer GN Nettest Optical Division 109 N. Genesee St. Utica, NY 13502 PH: 315-797-4449 FAX: 315-797-8024 EMAIL: [email protected] ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected] ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected] ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected]
