Creepage and Clearance (072)

[@joelsciamma9322]

Thanks, a very good way to remember the difference between the two. Access to standards information of all kinds is a complete pain for hobbyists and inventors.

[@eie_for_you]

You are welcome! You are right! It is tough to find affordable copies of standards. We have to settle for older versions ... but, like I said, we need knowledgeable guidance not certification. 🙂

[@WECB640]

Well done Ralph! I'd like to add (for the reader that may not have encountered this yet) that "creep" also applies to receiver circuits as our components today are usually of a much higher impedance (FETS and IC's) than decades earlier (bipolar transistors). The contamination on the board can detune high Q critical circuits, cause a condition that resembles thermal drift as the humidity is dried out and also create noise and instability. That's been my observation. Cleanliness is next to Godliness. Keep up the outstanding lessons. 73 OM

[@eie_for_you]

Oh yeah! I've seen that on high impedance timing circuits, too. Clean, clean clean!!! Thanks!🙂

[@W1RMD]

Excellent comment!

[@eie_for_you]

@@W1RMD True that! 🙂

[@Vincent-zz4xh]

Got a good information on this clip Mr.Ralph Tolute 😊

[@eie_for_you]

I'm so glad that it was helpful to you! Thanks! 🙂

[@W1RMD]

Is it spelled that way or is it "toot- a- loots"?

[@eie_for_you]

@@W1RMD LOL! I've always spelled it "toodle-oots" but MSWord's read aloud pronounces it very stupid. I have to spell it "toodle loots" for it. Internet search comes up empty (it guessed at "toddler boots" LOL!) 😀

[@W1RMD]

Also watch for "tin whiskers"! Great video! That would explain the notches cut out of SMPS circuit boards bridged by an optocoupler.

[@eie_for_you]

Oooooohhh yeah! The joys of lead free solder! I will not use lead free solder here in the shop. It is way too much of a pain. I have a pretty healthy supply of 60/40 solder so I don't think I will run out. When I first encountered the slot under an optocoupler I was puzzled. Then I learned about creepage. Mystery solved. Thanks! 🙂

[@W1RMD]

@@eie_for_you NO 63/37 either!

[@eie_for_you]

@@W1RMD True that! 🙂

[@bloguetronica]

Great explanation!

[@eie_for_you]

Thanks! 🙂

[@donnymac575]

You can purchase relatively cheap versions of standards from the Estonian Center for Standardization 😊.

[@eie_for_you]

Thanks for the tip! 🙂

[@cornbread-KO5RN]

👋

[@eie_for_you]

Thanks!

[@ornithopterindia]

👍Thank you sir.

[@eie_for_you]

You are welcome! 🙂

[@cornbread-KO5RN]

You can’t put a price on fun , spend that $20 bucks … 😂👋 wait, did someone say free , 👍

[@eie_for_you]

Yeah ... free! 🙂

[@Wandering_Horse]

Conformal coat sounds great until your the guy doing the repair. I do mil-spec circuit cards and just stabbing your leads through the coating to get a reading is enough to bend probes. Some boards have ridiculously thick coatings of what seems like straight up varnish. Then when you try to remove the conformal coating with acetone it just smears all over and creates a sticky mess.Paint thinner won't even touch, basically just giving it a spit shine! Some of the mil-spec stuff has to be scraped off or just melted through with the soldering iron. Its nasty stuff, unless you absolutely need it I would steer clear of it. And yes we do recoat our repairs with that stuff. We have had some parts come in from other repair shops that have used nail polish, stuff of nightmares!

[@eie_for_you]

Yup! I've had to deal with conformal coating a LOT! And you are right, it IS a pain. All of the products we manufactured were intended for an outdoor location, so conformal coating was kind of a requirement to keep the circuitry itself clean. It was a protective coating as opposed to extending the creepage distance (although we DID enjoy that benefit on a few occasions). When we would have to work on boards, we used a specially formulated conformal coating remover which worked real nice. It was amazing how that coating just came right off. Worth every penny we spent on buying the right solvent. You are right, though. If you can avoid it ... avoid it! 🙂

[@berndb.5097]

So what our head of development says isn't true. He always claims that the Americans have never heard of it.😁 Well, I know better now 😉 Thank you Ralph

[@eie_for_you]

I have run into a lot of such misconception about Americans. As a product design engineer, I had to be concerned with this all of the time. I'm glad that I've been able to dispel one more misconception. Maybe you could point your head of development to this video(??). You are very welcome! 🙂