George, Yes, I know. I've taken a good bit of data from your site, but you have 2 different one. A table of IPC (which I'm surprised they haven't said anything about that one) and a calculator that isn't from IPC but generated by a formula from some other gentleman that has done the research. (I must say I attempted to use that formula and came out with 1 decimal place off.) I'm sure it works but is implementation into a stand alone - offline calculator isn't there. (unless you are talking about another one.) If IPC was a little more friendly to this area you wouldn't have to have the site at all. George, I do want to thank you and others like you that have taken the IPC and other information and made it into a cleaner and more user friendly version. The personal time you have invested into supplying other designers, many times goes unappreciated. I appreciate what you have done and hope you will continue to clarify information. I also have a site (www.robertsondne.com) that leans towards the software I use and the manufacturing aspect more. Included is some modular notes, stand alone (somewhat) calculators and such. I don't want anything except to eliminate the relay of information to designers. I attempt to add the manufacturer's standards with IPC/generic design standards so the users may view the full scope of tolerances and specifications. Most of these are rules of thumb that I learned, before I learned of IPC.... More later. Chris Robertson [log in to unmask] > I have a trace width calculator on my web site at > http://www.aracnet.com/~gpatrick in the "PCB Data" section. It is based on > equations from IPCWorks 97 (McHardy/Gandhi, Hughes Aircraft TP SO6-2-1). > > There is already some slack in the calculations, but it depends on the > nature of the surge as much as how much surge current you are handling. If > you are worried about a surge that occurs infrequently, for very short > periods you might be able to go with the calculated value. What I normally > do is calculate width at the steady-state current at a 10 degree rise, > calculate trace width at the surge current at a 60 degree rise, then decide > how wide to make the trace based on the time the surge is expected to be > present. > > I am planning on incorporating some "fusing current" calculations into the > calculator when I get a spare moment. These are based on a presentation > from Doug Brooks at PCB East 2000. > > -- > George Patrick > Tektronix, Inc. > Central Engineering, M/S 39-512 > P.O. Box 500 > Beaverton, OR 97077-0001 > Phone: 503-627-5272 Fax: 503-627-5587 > > > > -----Original Message----- > From: Amira Mohammed [mailto:[log in to unmask]] > Sent: Monday, February 26, 2001 01:39 > To: [log in to unmask] > Subject: Re: [DC] Trace width > > > Dear Phil and Gary, > > Thank you for both of you > You are right .When I've asked about this,I told that we want some safty > factor for surge current , so should I calculate the trace width depending > on the maximum current value may be take place due to surge current, or > there is another way to calculate it? > Thanks in advance > Regards, > > Amira Mohamed > PCB Designer > IEP > www.bahgat .com > > > > > ---------- > > From: Gary Ferrari[SMTP:[log in to unmask]] > > Reply To: DesignerCouncil E-Mail Forum.;[log in to unmask] > > Sent: Monday, February 26, 2001 4:21 AM > > To: [log in to unmask] > > Subject: Re: [DC] Trace width > > > > Amira, > > > > I tend to agree with Phil on this one. The 5 amp current should be a > > continuos value. Is there any possiblilty that you may be seeing a surge > > current of a much larger value when you turn on the circuit? > > > > Regards, > > > > Gary Ferrari > > Executive Director > > IPC Designers Council > > 860-350-9300 > > Fax 413 771-5386 > > [log in to unmask] > > > > -------------------------------------------------------------------------- -- > ----- > DesignerCouncil Mail List provided as a free service by IPC using LISTSERV > 1.8d > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF DesignerCouncil. > To set a vacation stop for delivery of DesignerCouncil send: SET > DesignerCouncil NOMAIL > Search previous postings at: www.ipc.org > On-Line Resources & Databases > > E-mail Archives > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 > ext.5315 > -------------------------------------------------------------------------- -- > ----- > > -------------------------------------------------------------------------- ------- > DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF DesignerCouncil. > To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL > Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 > -------------------------------------------------------------------------- ------- --------------------------------------------------------------------------------- DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF DesignerCouncil. To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------