I would suggest a spark gap designed into the artwork. These work very effectively. Thank you Charles Grasso (Capn Hook)
> ---------- > From: UMBDENSTOCK, DON[SMTP:[email protected]] > Sent: Tuesday, December 08, 1998 11:26 AM > To: 'EMC-PSTC Discussion Group' > Subject: Signal Line Output Surge Protection > > One of our products required surge protection on a transmit output line to > comply with a UL requirement. The designer chose an MOV across the > differential output. When we performed a radiated emissions measurement, > we > found the previously compliant design to be "screaming" (~ 15 dB over the > limit). Removing the MOV resolved the EMC problem, but then we have the > UL > problem. > > The protection we were looking for was 120 V clamp, capable of handling a > 3 > joule test with a peak voltage of 2400 V applied. > > Just curious, has anyone had a similar situation? A particular supplier > indicated that others had reported MOVs to be disastrous from an EMC > perspective. MOVs appear to be a device with a general rule of thumb > "don't > use on 'signal' lines". Any experiences you would like to share? What > was > your solution? > > Regards, > > Don Umbdenstock > Sensormatic > > --------- > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to [email protected] > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to [email protected], > [email protected], [email protected], or > [email protected] (the list administrators). > --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators).
