Pete, Is this a 'typical' reactance, and a similar capacitance as used in the IEC60990 networks?
Brian From: Pete Perkins [mailto:[email protected]] Sent: Friday, October 10, 2014 5:30 PM To: [email protected] Subject: Re: [PSES] Human fingertip capacitance. Gary, The modeling of the human body from an electrical point of view has been going on for almost 100 years with major strides in understanding in the '40s & 50's and major gains again in the '90s with the advent of CAT/MRI scans providing overload detail in the body construction. The developers of IEC 61201, 'touch voltage threshold values for protection against electric shock', have used commonly accepted values in developing their evaluation as presented within that standard. Specifically, the capacitance of human skin used is in the range of 0.01 uF/cm2 to 0.05 uF/cm2 with a median value of 0.03 uF/cm2. Fingertip contact is in the range of a few cm2, from my experience. Perhaps this is adequate info for you to move ahead in your work. :>) br, Pete Peter E Perkins, PE Principal Product Safety Engineer PO Box 23427 Tigard, ORe 97281-3427 503/452-1201 fone/fax [email protected] _ _ _ _ _ Trying to set up a jig to test some capacitive touch-panels. It's an automated probe that disturbs the capacitive field of the sensor - but I'm clueless what kind of value to shoot for. I thought about the ESD gun capacitance but I don't know if that actually matches a human fingertip - or it's the whole body, or that the capacitance of the body of the ESD gun itself is used to calibrate to some human figure tip capacitance. I've got some research to do but does anybody have a starting point and a reference for the capacitance of an average human fingertip. I have the EE working the design to go back to the component supplier but haven't heard back from them yet. Thanks Gary McInturff Reliability/Compliance Engineer Esterline Interface Technologies Featuring ADVANCED INPUT, GAMESMAN, and LRE MEDICAL products 600 W. Wilbur Avenue Coeur d'Alene, ID 83815-9496 Toll Free: 800-444-5923 X1XXX Tel: (208) 635-8 Fax: (208) 635-8 - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
