Pete Perkins said: “A major difficulty is that the body effects are from the current while the product committees would like to specify voltage, which is easier to measure and verify compliance.”
I’ve had occasion to review a number of IEC safety standards for limits on voltage and current: IEC 61010 Safety requirements for electrical equipment for measurement, control, and laboratory use IEC 60950-1 Information technology equipment – Safety – Part 1: General requirements IEC 60335-1 Household and similar electrical appliances – Safety – Part 1: General requirements IEC 60065 Audio, video and similar electronic apparatus – Safety requirements IEC 60601 Medical electrical equipment – Part 1: General requirements for basic safety and essential performance IEC 61347-1 Lamp controlgear – Part 1: General and safety requirements IEC 62368-1 Audio/video, information and communication technology equipment – Part 1: Safety requirements Each of these safety standards specifies limits for accessible voltages and currents. If the prospective touch voltage exceeds a specified limit, the touch current must not exceed the specified limit. The current requirement is not prominent in most of these safety standards. IEC 61347-1 specifies “effective touch voltage,” 34 volts peak maximum, by using a 50 k resistor; the current at 34 volts peak is 0.68 milliampere peak or 0.48 milliampere rms. One measurement, voltage, accounts for both touch voltage and touch current. See Flore Chiang’s presentation at the 2012 Symposium, “Prospective Touch Voltage.” Best regards, Rich - ---------------------------------------------------------------- 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]>
