Thanks, sorry i should have said , this flyback needs the neutral carrying through to sec side, so its half wave rect and no isolation even though flyback.a flyback running offline, i.e. off the line, or mains is by definition - isolated -
I'm assuming this isn't a typo and you're referring to a different spec than I was referring to. I don't own 61010-1, but I'll take your word for it. It's not surprising that it has more lax standards than ME equipment. Anyways, it's not clear which standard is relevant for the OP's application...Please notice that clearance/creepage requirements are in IEC 61010-1 chapter 6
Thanks, i see your point....obviously the whole pri and sec is deiberately non isolated so no safety standard as such. (the neutral must be carried right through from pri to sec side)I won't expect reinforced insulation requirements (3500 V test voltage for 150 - 300V mains circuit) inside the hazardous circuit part, even in a medical standard.
Sorry, my fault. You are referring to medical safety standard IEC 60601-1. But apart from slightly stricter requirements, the basic idea of protection against electrical shock is the same in all safety standards.
I won't expect reinforced insulation requirements (3500 V test voltage for 150 - 300V mains circuit) inside the hazardous circuit part, even in a medical standard.
I think the main difference is that in 60601-1, two means of protection are required (for both operator and patient). Also there's no concept of a "hazardous part" or SELV in 60601-1. In the case where the output of a mains-connected PSU is connected to protective earth, that counts for one means of protection. The other MOP typically comes from the PSU's protective insulation, i.e. creepage/clearance and solid insulation, Y caps, etc. It could be basic insulation instead of double/reinforced, so the test criteria are relaxed a bit, but still there. For 60601-1-11 (home healthcare), the protective earth connection doesn't count as a MOP, meaning you still end up wanting a transformer rated for 4kv...I had a brief look at EN 60601-1:2006. Clearance and creepage requirements refer generally to IEC 61010. A special point are additional requirements for protection means of circuit accessed by patient. For internal isolation of power supply circuit, there's a similar requirement as mentioned in post #9. Circuit nodes of opposite polarity up to and including the input fuses need to observe clearance/creepage requirements. No test voltage defined for it. Operator protection means use regular double/reinforced insulation as we know from other standards.
What safety standards apply is generally not up to us engineers. I mean, in theory even compliance with IEC 60601-1 is not mandatory to get FDA/CE approval to sell ME equipment. But good luck convincing them.Thanks, i see your point....obviously the whole pri and sec is deiberately non isolated so no safety standard as such
What standard are you referring to here??The thing is....that standard ("3500vac for x seconds") presumably exists because there is a real danger of 3500VAC appearing between the pri and sec in real life.....that must be the case, otherwise the standard wouldnt be written like that.............
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