The problem is that when you spread quotes from AI you feed AI with AI generated content. AI is useful if you use it and can test or verify the results, and then give the result to others in your own words.
Not a big deal in this case, but we shouldn’t be part of deteriorating the internet.
Sadly there is little you can do, that is the nature of the Internet now the “AI’s” of which I am no fan, are trained on forums like this and all the others. Be reminded what The Bald Engineer wanted to do was remove his contributions to the ‘Internet’ and basically he can’t 
but anyway as you say no harm done but let me give you a bit of context here. I observed the OP’s question and it was dead simple in fact I am the one who gave the solution the OP was happy with 
I was amused at the array of answers that started with a miss understanding went through ‘current transformers’ then came protocols and a bit of life stories for good measure and I thought to myself " I bet this OP wishes he had asked bloody Chat GPT" at this point I laughed to my self and the rest as they say is history 
I suppose, one day in the future, if we see the term “misteeks” used by Chat GPT, we will know this forum, and Bob in particular, has contributed to its written diarrhea.
But isn’t the description correct otherwise?
What I would do is look at the part and make a judgement on the required clearance based on how well it’s likely to be made, specifically regarding tolerance in pin spacing and pin diameter. Then add in something appropriate. You might be able to get this from the data sheet but more than likely not. In the absence of anything else, I’ll usually go about 10% for a ‘good’ part eg 1.0mm hole for a 0.9mm pin, but you may want to have more clearance if you are concerned about it - I would think a current transformer might need more clearance since the coil former possibly might not be so accurately moulded.
The other thing I would do is try to measure what you have ie the pin and the hole. See how they match up. With digital verniers this is more achievable than you might think.
I know, back in the olden days, hand stuffing THT components into wave soldered single sided boards resulted in, a few years later, severe cases of dry joints where the components were physically large and the holes a very loose tolerance. Rivets through the holes in the PCBs were the cure of the day back then.
I’ve still seen this practice in fairly recent use. An example being cheap desktop computer power supplies. Rivets through holes in single sided boards for switching transformers and transistors and big electros.
Hand soldering on double sided boards is not so much of a problem, but I’m still dubious about over-sized holes for any product, even one-off hobby stuff.
I do like the specs in the document offered up by @JohnRob . 
Maybe it’s stating the obvious, and really not what you asked, but most components have a “manufacturers recommended footprint” in the datasheet where these dimensions are stated.
Looks like I really started something here! 
Here’s what started it all: I have a board that includes a current sensing transformer. The leads are round, .84mmin diameter. I could not find a footprint so I stumbled through creating my own. Not really knowing what I was doing, and not being really well versed in metric measurements, I made the holes, if I remember right, .9 in diameter. The device would mount on the board but it took some force to get it to seat. And after assembly, the slightest flex of the board would cause a bad solder joint. Obviously, no solder was able to get into the holes and the very small annular ring didn’t have much mechanical strength.
Here’s what I did: I increased the hole size to 1.02 and increased the size of the pads. Mousey suggested that size and it was a pretty strongly worded. So, I accepted his recommendation. That’s not to say I was unhappy with any of the other replies I got. I have Reordered the boards and am waiting for them.
Oh! I also increased the 0402 resistor and LED to 0805.
I guess I wrongly used the word clearance to mean the spacing between the diameter of the pin and the diameter of the hole rather than the space between the different thingies on the board so they don’t bang into each other. Still can’t think of another word to describe what I meant.
Anyway, I proud of the discussion I prompted. It’s been a lot of fun.
Thanks to all!
Bart
BTW I was always of the opinion that solder is not a structural component. Although I do realize SMD parts are all (at least mostly) retained by solder.
Would be curious of what your current sensing transformer was. Could you post a spreadsheet?
True.
It is mainly the thermal expansion and contraction causing the wave solder cracking around pins on larger components. Again, this is mainly cheaply manufactured domestic products.
Double sided boards with plated through holes are a far more robust product.
Here’s the data sheet for the sensing transformer:
CS1050L.pdf (184.7 KB)
I am using the D1869L version. I was told by Coilcraft the these are designed to be used to actually measure the current whereas I am using it to simply detect the presence of current flow. The board I made is used with a system that provides a DC voltage of 14 volts with a PWM signal imposed over that. It will detect the draw of a 10k resistor.
Bart
Yeah 
Great fun was had by all ! I’m glad your boards are off to be made and I’m sure they will be perfect, and I think going up in size to 0805 was the right move because if your not experienced with 0402 you are going to have a dreadful time of it 
every now and then wording can lead to misunderstandings but it usually all comes out in the wash 
And proud you should be ! I hope you will be back with more questions and the result of your new board
I would probably use “the difference in the diameters of the hole and pin”.
Perfect 
However If I may be so bold as to suggest " The difference between the diameter of the hole in the PCB and the diameter of the component lead" would also be a worthy candidate for the role of description
“I guess I wrongly used the word clearance to mean the spacing between the diameter of the pin and the diameter of the hole rather than the space between the different thingies on the board so they don’t bang into each other. Still can’t think of another word to describe what I meant.”
It was plain to me from your initial question, and cemented by your next reply. And the answer really was pretty simple: use your judgement, as there is no hard and fast rule applicable to every design.
Do not feed the troll. And you really shouldn’t have to disclaim your question as to not be asking for someone to design the part for you. Too many sharks waiting to take a bite out of an innocent requester…not good.
Cheers.
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@BartH - great topic and discussion. I learned a lot.
Many choices should be adjusted based on your PCB manufacturer so that you stay within their capability limits. They will call out those on their capabilities pages, typically found online. You should check there in addition to the great information given here. Mine says:
On the annular ring size: “The pad size will be enlarged by 0.5mm than the hole size.” so the annular ring size is 0.25mm.
Drill Hole Size Tolerance: +0.13/-0.08mm—For the 0.6mm hole size, the finished hole size between 0.52mm and 0.73mm is acceptable. So, when you said 1.02mm, that would be plus or minus something based on your manufacturer’s build facility tolerances.
PTH—Plated Through Hole—which for a single-sided board would not apply, would close the hole size down from what you had asked them to drill. My manufacturer does .5oz copper plating for that, which is 17um thick. So, 2 sides * 17um would be the amount of closedown.
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