We did similar tests, but on 120/240 V panels. Silicone coatings performed the best, although no part was over 500C. Arcing was induced by saltwater dropped directly over the 120/240V input lines. Silicone can burn, but is inherently flame resistant. Organics can be formulated for similar effects, but only silicones can withstand 500C for over a brief exposure without damage. Suppliers evaluated: Dow Corning W. R. Grace, also known as "Emmerson & Cumming" or "Grace Specialty Polymers" Good luck. ______________________________ Reply Separator _________________________________ Subject: ASSY: Conformal Coating Flammability Problems Author: [log in to unmask] at internet Date: 11/26/96 6:45 PM During field trials of our existing coating (High Solids Xersin) on high powered PCA applications, we found that due to a component failure, that the PCA suffered badly from fire damage (an area about 75mm sq was severely burnt - even the copper tracks were melted). Upon testing (using a coated resistor - to specified thickness & making it fail) we found that generally the solvent based coatings showed a noticeable increase in the flame produce, when subject to high temperatures (eg components failure - over 500oC). Additionally, the organic based coatings also produced an unacceptable amount of carbon and it was these two factors which we believe damaged our PCA (the carbon increased the area shorting from being localised). Could anyone suggest a Conformal Coating that may be acceptable to high powered PCA applications, suitable for application by a select coat system? We believe that Silicon based coatings may be the best choice, but samples are slow in coming to Australia for trial and all the coating spec's mention that they pass flammability tests. Thanks, Paul Moro Manufacturing Engineer COM10 (Austrialia) Tel 61-2-9722 3310 [log in to unmask] *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ***************************************************************************