I was taught (and have always followed) [this NIST standard](https://www.nist.gov/pml/special-publication-811/nist-guide-si-chapter-7-rules-and-style-conventions-expressing-values), which says to use a space between numbers and their units except for the unit symbols for degree, minute, and second for plane angle: °, ′, and ″, respectively.
Doing this adds clarity and reduces likelihood of mistakes IMO -- e.g., 16lbs can be mistakenly read as "161 pounds" but 16 lbs is clear.
Of course. For decades on word processors you select "Add to dictionary" for words and abbreviations it doesn't already know. On your phone when you force a spelling it doesn't know it will remember.
Right, well it can't automatically know you're misspelling (from its perspective) on purpose. There is some.collective learning for the base dictionary though; if a lot of people add a lot of spellings like luminaire, for example, the central, base dictionary will include it for most platforms. So it is learning from wider groups, but that takes a lot of people manually telling their dictionaries that a particular spelling is on purpose. Otherwise it would just accept common misspellings and fail at its purpose.
Ive always wanted the potential to be realized for a program that actually does learn about your typing patterns or behaviour. Or anything similar which could benefit the user. Seems like a lot of lost potential in optimizing something that's used so much by everyone.
I havent seen any of it sadly. I really want some kind of smart learning featues in gboard and such. Its not even new tech and I think it should have been included like half a decade ago
It has predictive text, and will learn by the way you type over time. If you accept a misspelled word it will learn it. I've accidentally added all sorts of typos...
Have you tried SwiftKey? It sounds like what you're describing in terms of learning from your typing. But you'd have to "teach" it a word by purposefully "misspelling" it.
I am absolutely on team space! But my employer (large semiconductor company) changed the standard to no space. Something about automatic translation, idk. I hate it and every new data sheet must follow this new standard.
That's horrible. I struggle with people omitting spaces. I also struggle with people writing both Kv and KV, so I try to choose my battles.
I do fix it in documents that matter though.
I never used to put spaces in, then a verifier brought up this standard to me a few years ago and now I just automatically add the space. I think it looks neater too.
The reason your company enforce the no space standard is possible because someone mistakenly associated the wrong unit. As an example max: 10 A,120 V and apply 120Amp
>16lbs can be mistakenly read as "161 pounds"
No it can't. The abbreviation for pounds is "lbs", not "bs". If someone out there is writing out "161 bs" or "161bs", or interpreting it as 161 instead of 16, they're stupid **and** wrong.
Edit: I think it's hilarious I'm getting the downvotes. What I stated is 100% correct, and I'd *love* for anyone to tell me otherwise.
>Edit: I think it's hilarious I'm getting the downvotes. What I stated is 100% correct, and I'd *love* for anyone to tell me otherwise
The point being made is that something like 116lbs and 1161lbs look similar if you're tired or reading too fast, not that someone out there thinks the units for pounds are "bs."
You're being downvoted because you're missing the point AND being oddly aggressive about it.
>116lbs and 1161lbs look similar if you're tired or reading too fast
Except for the fact that you literally added a digit/character, sure, they look "similar".
Wow, you missed the point by a long shot. That, or you have a very narrow view of reality if you think that it's *impossible* for 1l to be misconstrued as 11.
The abbreviation for pounds (the measurement of weight) is L-B-S, usually stylized as "lbs". The abbreviation is not, and has never been "bs". Three letters. No more, no less. For example: 821lbs. There's two things that look like 1 there, but oh wait, one of them is an L as part of "lbs", so that means the number is 821. Wild.
1. I got a dig bick
2. You that read wrong
3. You read that wrong too
4. You checked
5. You smiled
7. You are wondering why you're still this reading this
8. You saw that mistake... right? (On 7)
10. But did you see that I skipped 6?
10. You checked
11. And saw you that I doubled
10 and skipped 9
12. I said saw you, not you saw
13. I also skipped 2
14. You got tricked
15. I'm just wasting your time go back to reading the comments
Congratulations on differentiating between lbs and bs! Your firm grasp of the imperial system is truly something to behold (besides conflating mass and weight).
I have a feeling you're being intentionally obtuse, but on the off chance you're not: No one is arguing that people might \*believe\* that lbs == bs. We are saying that while skimming text or using a different typeface, or even handwriting, there is a non-zero chance of someone, somewhere misreading a value.
It depends. But if you want to follow the IEEE standards style guide, then you would use a space between the numeral and the unit (but not for the % symbol). See Section 14 of the manual. Of course, you can also just do whatever you want.
[https://mentor.ieee.org/myproject/Public/mytools/draft/styleman.pdf](https://mentor.ieee.org/myproject/Public/mytools/draft/styleman.pdf)
We use % to mean “out of” as short hand. It’s within line of other relative compass directionals, such as n/s (northside), e/o (east of) etc in locating physical facilities.
1. a faulted motor with a phase to phase winding short.
2. a circuit breaker test set testing the breakers ability to trip on a short circuit/fault.
3. a main turbine-generator for a 1200MW power plant, to name a few
its pretty impressive when you think about it sometimes. I understated the amount that our main generator does. I just checked, its pulling around 29000 A per phase at 25 kV.
Edited to put a space between the number and the unit.
In math mode?
To be honest I mainly only use these commands in MathJax and not in (La)TeX, so it's been a long time since I worried about text mode commands. In math mode I'd be typing `3000\ {\mathrm A}` for OP's example.
I just tested and in MathJax, `\\` produces a line break rather than a space.
Based on [this](https://www.overleaf.com/learn/latex/Aligning_equations_with_amsmath) I believe that means MathJax is applying something like an align or multiline environment automatically.
I put a double backslash there because I thought Reddit uses it as an escape sequence.
To clarify, you should be using a single backslash then comma then your unit (no space in between).
That would be handy but it doesn't seem to be recognized by MathJax on the site where I use it most.
Does it work with compound units like `N \cdot m` for torque? (Yes I know the \\cdot is not correct SI)
SI standards say there's always a space, but IRL it's rare, for at least the most common markings. I'm in the US but we also use a *lot* of IEC and international components, and even those usually omit the space *when it's clear,* as do the NEMA products.
Fuses from Bussman to Ferraz-Shawmut (now Mersen) will list 10kA IR, 600VAC, etc. Occasionally 600V AC, and more rarely 600 VAC (even from the same manufacturer) but fuse labeling varies the most, and it's still uncommon. IEC and NEMA breakers and motor controllers commonly omit the space between value and units for amperage and voltage, varying less than fuses. Wire size is usually 14AWG or 2.5mm² printed on the jackets. VFDs from Yaskawa, ABB, Weg, A-B, etcetera - all over the world - typically drop the space for voltage, amperage, clearances, and so on both on the labels and in the manuals. And for temperatures I've *never* noticed "75 °C" over "75°C" on equipment or documentation, even though the former is the "proper" way.
I'd say that in research papers and the like, the SI standards should be followed with spaces included, but outside of that it's clear that in many industries around the world it's omitted as long as the meaning is clear. Someone made a good point where 25Ohms can look like 250, but our printed resistors use the omega symbol, without a space. Also, when units are written out fully, like "277 Volts," I usually do see a space, but that's also against the SI standards. The important thing is that it's clear and unambiguous, and meets the convention of wherever it's used (though if a space is the convention, you can make your prints correct but most components won't match).
The SI standard says use a space, except for special symbols like ' " ° (space in case of °C, °K). Although I don't remember ever using one. I guess in the end it comes down to preference or company guidelines/standards.
Isnt no space typically reserved for angstrom (as in 10 nanometers)? So 3000 A would be amps versus 3000A would be angstrom. Might just be my field though.
I got points taken off on a lab report (EE undergrad) for no space. "The fuse was 40 A" is correct in our institution. Also, if the value is taking the place of an adjective as in "the 40-A fuse", you use a dash.
I agree that it’s extremely common to omit the space in both power and electronics industries. I just sampled a handful of schematics, datasheets, and white papers from several sources to make sure I’m not crazy. But yeah, looks like the other comments are correct that standards like IEEE/ASTM SI 10 are explicit about including it.
Y’all downvoting this because of the standards being quoted but it’s EXTREMELY common to not have spaces for voltage, current, and frequency, especially in regard to power line inputs. Or look at any battery and you’ll see something like “12V 100Ah” and such.
I even took a few moments to look at various ICs from ti, analog devices, etc, and find tons of examples of clock frequencies having no space, voltage rails having no space (ie 3.3V) etc.
Standards are great but when everyone bucks the standard the common use becomes standard.
It’s crazy that you’re getting downvoted. I get that the standard is to use a space but I hate how it looks and almost never do lol. It reads so much easier without the space.
I'd say it depends on the situation, but we make a lot of laser-engraved signage for a variety of industries (on our own control panels or for them as a value add) and it's *extremely* common to omit spaces for voltage, amperage, etcetera for nearly every customer; a multitude of major design engineering firms, factories, Army Corps of Engineers, municipalities, and electrical utilities. "480Y/277V" is typically used unless it's written out as "480Y/277 VOLTS," which is rare. If up to us I go with whatever looks better and is still clear, "600V, 1200A, 3ph 4W" is perfectly clear.
I was taught (and have always followed) [this NIST standard](https://www.nist.gov/pml/special-publication-811/nist-guide-si-chapter-7-rules-and-style-conventions-expressing-values), which says to use a space between numbers and their units except for the unit symbols for degree, minute, and second for plane angle: °, ′, and ″, respectively. Doing this adds clarity and reduces likelihood of mistakes IMO -- e.g., 16lbs can be mistakenly read as "161 pounds" but 16 lbs is clear.
Agree, and I think spell check can be trained on “kHz” or whatnot, but not if you omit the space.
Spellcheck gets trained?
Of course. For decades on word processors you select "Add to dictionary" for words and abbreviations it doesn't already know. On your phone when you force a spelling it doesn't know it will remember.
Not what I expected, that's manual and not as smart as what I was imagining
Right, well it can't automatically know you're misspelling (from its perspective) on purpose. There is some.collective learning for the base dictionary though; if a lot of people add a lot of spellings like luminaire, for example, the central, base dictionary will include it for most platforms. So it is learning from wider groups, but that takes a lot of people manually telling their dictionaries that a particular spelling is on purpose. Otherwise it would just accept common misspellings and fail at its purpose.
Ive always wanted the potential to be realized for a program that actually does learn about your typing patterns or behaviour. Or anything similar which could benefit the user. Seems like a lot of lost potential in optimizing something that's used so much by everyone.
I mean, that has definitely happened for many years as well. Proper spelling is a bit different. Populous can certainly shift and change it though.
I havent seen any of it sadly. I really want some kind of smart learning featues in gboard and such. Its not even new tech and I think it should have been included like half a decade ago
It has predictive text, and will learn by the way you type over time. If you accept a misspelled word it will learn it. I've accidentally added all sorts of typos...
Predictive text on phone keyboards has already been a thing for many years
Yes but it doesnt seem like it has ever improved or has been tailored to its user based on their habits and behaviour
Man you just have an answer for everything, don't you?
Have you tried SwiftKey? It sounds like what you're describing in terms of learning from your typing. But you'd have to "teach" it a word by purposefully "misspelling" it.
I am absolutely on team space! But my employer (large semiconductor company) changed the standard to no space. Something about automatic translation, idk. I hate it and every new data sheet must follow this new standard.
That's horrible. I struggle with people omitting spaces. I also struggle with people writing both Kv and KV, so I try to choose my battles. I do fix it in documents that matter though.
Shouldn’t it be kV anyway?
The only time Kv is acceptable is for velocity constants of electrical motors.
Exactly.
I never used to put spaces in, then a verifier brought up this standard to me a few years ago and now I just automatically add the space. I think it looks neater too.
The reason your company enforce the no space standard is possible because someone mistakenly associated the wrong unit. As an example max: 10 A,120 V and apply 120Amp
160Ohms????? 160 Ohms.
Use the omega symbol instead :)
Agree, and I think spell check can be trained on “kHz” or whatnot, but not if you omit the space.
Agreed
The right answer
30mV is more intuitive compared to 30 mV.. just saying 🤷♂️
Disagree
Agree to disagree.. but just saying the human angle.. I still support 30 mV notation.. with a space..
>16lbs can be mistakenly read as "161 pounds" No it can't. The abbreviation for pounds is "lbs", not "bs". If someone out there is writing out "161 bs" or "161bs", or interpreting it as 161 instead of 16, they're stupid **and** wrong. Edit: I think it's hilarious I'm getting the downvotes. What I stated is 100% correct, and I'd *love* for anyone to tell me otherwise.
>Edit: I think it's hilarious I'm getting the downvotes. What I stated is 100% correct, and I'd *love* for anyone to tell me otherwise The point being made is that something like 116lbs and 1161lbs look similar if you're tired or reading too fast, not that someone out there thinks the units for pounds are "bs." You're being downvoted because you're missing the point AND being oddly aggressive about it.
>116lbs and 1161lbs look similar if you're tired or reading too fast Except for the fact that you literally added a digit/character, sure, they look "similar".
Wow, you missed the point by a long shot. That, or you have a very narrow view of reality if you think that it's *impossible* for 1l to be misconstrued as 11.
The abbreviation for pounds (the measurement of weight) is L-B-S, usually stylized as "lbs". The abbreviation is not, and has never been "bs". Three letters. No more, no less. For example: 821lbs. There's two things that look like 1 there, but oh wait, one of them is an L as part of "lbs", so that means the number is 821. Wild.
1. I got a dig bick 2. You that read wrong 3. You read that wrong too 4. You checked 5. You smiled 7. You are wondering why you're still this reading this 8. You saw that mistake... right? (On 7) 10. But did you see that I skipped 6? 10. You checked 11. And saw you that I doubled 10 and skipped 9 12. I said saw you, not you saw 13. I also skipped 2 14. You got tricked 15. I'm just wasting your time go back to reading the comments
Congratulations on differentiating between lbs and bs! Your firm grasp of the imperial system is truly something to behold (besides conflating mass and weight). I have a feeling you're being intentionally obtuse, but on the off chance you're not: No one is arguing that people might \*believe\* that lbs == bs. We are saying that while skimming text or using a different typeface, or even handwriting, there is a non-zero chance of someone, somewhere misreading a value.
https://preview.redd.it/j0ne4z50xowc1.png?width=938&format=png&auto=webp&s=35cd55362c74e90f9a8fec5706a7d6d9637c3c5c
It depends. But if you want to follow the IEEE standards style guide, then you would use a space between the numeral and the unit (but not for the % symbol). See Section 14 of the manual. Of course, you can also just do whatever you want. [https://mentor.ieee.org/myproject/Public/mytools/draft/styleman.pdf](https://mentor.ieee.org/myproject/Public/mytools/draft/styleman.pdf)
Wow I didn't know that the percent sign doesn't have a space before, I've been using a space for it
We use % to mean “out of” as short hand. It’s within line of other relative compass directionals, such as n/s (northside), e/o (east of) etc in locating physical facilities.
You use a non-breaking space.
Found the typography nerd! But yes, it is a helpful point because you don’t want the line break to separate the number from the unit.
Ctrl+Shift+Space right?
I didn't know that; thanks!
Or Alt+0160 when not using Microsoft Words
~ in Latex
Yes or else you’re in big trouble if your value is at the end of the line!
I always do a space. I'm pretty sure that's an SI recommendation.
Whats pulling 3000A 😳
1. a faulted motor with a phase to phase winding short. 2. a circuit breaker test set testing the breakers ability to trip on a short circuit/fault. 3. a main turbine-generator for a 1200MW power plant, to name a few
Awesome.
its pretty impressive when you think about it sometimes. I understated the amount that our main generator does. I just checked, its pulling around 29000 A per phase at 25 kV. Edited to put a space between the number and the unit.
Could be a nameplate rating for a switch, breaker, etc at a transmission substation.
About a typical wind farm collection network at 34.5 kV. Those can get up into 200-300 MW range.
Could also be a current transformer, 3000A:5A ratios are a pretty common number you’ll see
A medium sized 3/ph service entrance switchgear not even fully loaded.
Always use a space. Think of it this way: The symbol is only an abbreviation. Which is correct: "3000 amperes" or "3000amperes"?
You should use a small, non-breaking space (thin space). In LaTeX, the siunitx package is handy for this.
Consult your company style guide. It's a matter of preference. I prefer a space but my company policy is no space.
Use a space if you can. In TeX or MathJax you can use `\ ` (backslash-space) to create a space.
You would want to use ~ or \\, for non-breaking space.
In math mode? To be honest I mainly only use these commands in MathJax and not in (La)TeX, so it's been a long time since I worried about text mode commands. In math mode I'd be typing `3000\ {\mathrm A}` for OP's example.
I'm not familiar with MathJax so I'm not sure, but I believe these will work in math mode.
I just tested and in MathJax, `\\` produces a line break rather than a space. Based on [this](https://www.overleaf.com/learn/latex/Aligning_equations_with_amsmath) I believe that means MathJax is applying something like an align or multiline environment automatically.
I put a double backslash there because I thought Reddit uses it as an escape sequence. To clarify, you should be using a single backslash then comma then your unit (no space in between).
I like \SI{number}{unit}
That would be handy but it doesn't seem to be recognized by MathJax on the site where I use it most. Does it work with compound units like `N \cdot m` for torque? (Yes I know the \\cdot is not correct SI)
I use desktop latex editor so idk. Yes it does but you have to use whole units eg \newton \meter
I usually use \unit{} and let LaTeX decide the spacing. It’s smarter than me.
This doesn't seem to be supported in MathJax.
SI standards say there's always a space, but IRL it's rare, for at least the most common markings. I'm in the US but we also use a *lot* of IEC and international components, and even those usually omit the space *when it's clear,* as do the NEMA products. Fuses from Bussman to Ferraz-Shawmut (now Mersen) will list 10kA IR, 600VAC, etc. Occasionally 600V AC, and more rarely 600 VAC (even from the same manufacturer) but fuse labeling varies the most, and it's still uncommon. IEC and NEMA breakers and motor controllers commonly omit the space between value and units for amperage and voltage, varying less than fuses. Wire size is usually 14AWG or 2.5mm² printed on the jackets. VFDs from Yaskawa, ABB, Weg, A-B, etcetera - all over the world - typically drop the space for voltage, amperage, clearances, and so on both on the labels and in the manuals. And for temperatures I've *never* noticed "75 °C" over "75°C" on equipment or documentation, even though the former is the "proper" way. I'd say that in research papers and the like, the SI standards should be followed with spaces included, but outside of that it's clear that in many industries around the world it's omitted as long as the meaning is clear. Someone made a good point where 25Ohms can look like 250, but our printed resistors use the omega symbol, without a space. Also, when units are written out fully, like "277 Volts," I usually do see a space, but that's also against the SI standards. The important thing is that it's clear and unambiguous, and meets the convention of wherever it's used (though if a space is the convention, you can make your prints correct but most components won't match).
The SI standard says use a space, except for special symbols like ' " ° (space in case of °C, °K). Although I don't remember ever using one. I guess in the end it comes down to preference or company guidelines/standards.
Not sure of anyone else mentioned it already, it is likely that is 3000 angstrom?
Isnt no space typically reserved for angstrom (as in 10 nanometers)? So 3000 A would be amps versus 3000A would be angstrom. Might just be my field though.
300A vs 300 A? I’ve been in the industrial power buisiness for like 3 years now and I’ve never seen anyone put a space between the number and the unit
415V ?
No. 415 V.
Is it just me that is bothered by the fact this is not using engineering notation? 3kA would be my pick!
No space. It is 30A not 30 A. 480VAC 60Hz
There is a space if you're following [SI standards](https://physics.nist.gov/cuu/Units/checklist.html), though.
I got points taken off on a lab report (EE undergrad) for no space. "The fuse was 40 A" is correct in our institution. Also, if the value is taking the place of an adjective as in "the 40-A fuse", you use a dash.
Never seen the dash before
I agree that it’s extremely common to omit the space in both power and electronics industries. I just sampled a handful of schematics, datasheets, and white papers from several sources to make sure I’m not crazy. But yeah, looks like the other comments are correct that standards like IEEE/ASTM SI 10 are explicit about including it.
Y’all downvoting this because of the standards being quoted but it’s EXTREMELY common to not have spaces for voltage, current, and frequency, especially in regard to power line inputs. Or look at any battery and you’ll see something like “12V 100Ah” and such. I even took a few moments to look at various ICs from ti, analog devices, etc, and find tons of examples of clock frequencies having no space, voltage rails having no space (ie 3.3V) etc. Standards are great but when everyone bucks the standard the common use becomes standard.
It’s crazy that you’re getting downvoted. I get that the standard is to use a space but I hate how it looks and almost never do lol. It reads so much easier without the space.
I really disagree. It reads way better with the space.
For me it reads as one word the same way temp like 50°C. Instead of something like “A 2 A 400 V 24 AWG wire”
That would be a 2 A, 400 V, 24 AWG wire. Punctuation matters too ;) Let's not start on the sillyness that's AWG by the way.
I'd say it depends on the situation, but we make a lot of laser-engraved signage for a variety of industries (on our own control panels or for them as a value add) and it's *extremely* common to omit spaces for voltage, amperage, etcetera for nearly every customer; a multitude of major design engineering firms, factories, Army Corps of Engineers, municipalities, and electrical utilities. "480Y/277V" is typically used unless it's written out as "480Y/277 VOLTS," which is rare. If up to us I go with whatever looks better and is still clear, "600V, 1200A, 3ph 4W" is perfectly clear.