If the FR4 material has a decent CTI, for the expected Material Group and Pollution Degree of the end-use application, the 4.1mm creepage spacing would meet the requirements for AC mains isolation (250Vac) per Table 2n of the IEC/UL 60950-1 (product safety standard for information technology Equipment where only basic insulation is required that is, there is a reliable ground bound for expose metal otherwise, reinforced insulation is required, so the 4.1mm spacing would only be suitable for isolating two pieces of equipment that are both powered from the same AC mains phase (125Vac). But this spacing is disallowed for consideration because the creepage accross isolation boundary features of the PCB is approx 4.1mm that is, THE AVAILABLE SPACING ACCROSS THE ISOLATION BOUNDARY IS NOT 7mm AS WAS PREVIOUSLY STATED. Where used with power source rated Class 2 and Class II (in compliance engineering, these are different terms), the component is rated for up tp 600Vac WV where only BI is required, otherwise where reinforced insulation is required, WV rating is less than 250Vrms for RI.īoth components provide over 7mm creepage accross the body. The safety certifications have interesting Conditions of Acceptability. An interesting note for this component is that the device, when used with proper construction, is also certified for use in medical equipment where two means of patient protection are required ie where an instrument must be certified for patient contact.Ĭurrent test certificates apply only to North America. The component is intended to provide isolation from a hazardous voltage (eg AC mains) that is safe to touch. For a complete safety requirements analysis, please consult an accredited NRTL/SCC lab for use in North America.ĭepending on the particular model number of 4160 and the scoped safety standard for the end-use equipment, rated WV is from 125Vrms to 400Vrms. Please do not confuse rated working voltage with the rated di-electric withstand voltage.This analysis is not intended to be applied to any product for sale, or where the product is used in commercial equipment. Have reviewed the component's safety certificates and the PCB layout. Use incorrectly, could result in shock and/or fire hazard. Used within its limits, should preserve life and equipment. Hobbyist will use this so that they can use a mains-connected computer or test instrument on a widget that may be reference to mains neutral, hence the panel ground. To interrupt a current loop between secondary and mains typically requires BI for Class I construction, and RI for Class II construction. But this test level does nothing to indicate the rated working voltage of the device. The test level for Basic Insulation for stuff that is plugged in 240 mains is typically 1500Vac, assuming Class I construction. This is a test level that is based on end-use Installation Category and the measured working voltage. The correct term is "Rated Di-electric Withstand Voltage". The rated 'Isolation' voltage is NOT the same as the rated working voltage. basic, double, reinforced) and the measured working voltage across the isolation boundary and the what is exposed in the end-use construction.Īccording to the respective PCB layout on github, the available spacing is much less than 7.7mm. The 'standard' creepage and clearance depends on the scoped product safety standard and the type of insulation required (e.g. Please note following and please be careful not to mislead others on this important topic. The isolation gap down the center is the standard 7.7mm for 1.2kV isolation, but hasn't been tested at that voltage. Adafruit_support_mike wrote:I'm afraid we don't have any specs for those.
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