Hi, I have the IPC2221A table in my program. http://saturnpcb.com/pcb_toolkit.htm If you just need a distance from hole to copper without regard for electrical issues then this becomes a standard spacing issue, right? I would stay 50mils away from any mounting holes but it depends on the design. Hope this helps... Ken -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of GRIVON Arnaud Sent: Wednesday, March 04, 2009 5:38 AM To: [log in to unmask] Subject: [TN] PTV to Ground Clearance Hello TechNet, For those who are familiar with IPC-2221 and IPC-2222 standards : what are the recommended clearances between a PTV/PTH and an internal PCB ground plane? IPC-2222 §9.1.3 'Clearance area in plane' includes a picture with an 'A+B' distance corresponding to the summation of the electrical clearance and the manufacturing tolerances, but I cannot find any numerical values. Can somebody help? I am primarily interested in the case of an unsupported hole without NFP in a ground plane. Thanks in advance for your insights. Best regards, A. Grivon --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------