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Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 12:16 am
by tuffteef
im slightly confused by the values of the caps i need and ive done this so many times hahah
everythings in uF but on smallbear all the elec caps i need are in mF
i cant find a clear answer on it being the same like 47mf the same as 47uf

plus theres some stuff like
4u7
3n9
27n
2n2
82n
68n
390n
100n

i kinda get the like 4u7 is 4.7
3n9 = 3.9 but what though mf uf pf?

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 12:26 am
by McSpunckle
The most used ones go by thousands.

1uF is 1000nF, and 1nF is 1000pF

I'm sure you realize this, but for the sake of (especially) the American readers: uF = Microfarad, nF= Nanofarad, pF= Picofarad. The metric system! I FUCKING LOVE THE METRIC SYSTEM

So basically, to convert between them, you just move the decimal 3 places. EXAMPLES! FUCKING MATH!

47nF = .047uF = 47000pF
3900pF= 3.9nF = .0039uF (but it would be listed as .004uF probably)

And, yeah, when they're listed with the prefix in the middle of the number, that just means that's where the decimal goes. So, like you said, 4n7 is 4.7nF.

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 12:31 am
by tuffteef
so uF is just mF?

what about this letter in the middle business

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 12:38 am
by McSpunckle
I edited my post with the letter in the middle stuff.

Yeah. Sometimes uF is written mF. mF would technically mean millifarad, though, which is 1000 uF. But, that's never actually used. So if you see mF, it's probably uF.

Just to be super clear, the u doesn't make sense because the symbol isn't really u. It's μ. But that's not on a keyboard.

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 12:42 am
by mysteriousj
tuffteef wrote:so uF is just mF?

what about this letter in the middle business


Ya, americans always have to do things backwards ;)
m for micro I guess it kinda makes sense.

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 12:59 am
by tuffteef
neeto thanks kids
i must have a headache or something of why it wasnt computing

same deal for resistors
560R is 506ohm
1k5 1.5k
?

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 12:59 am
by eatyourguitar
^this yes you are correct

letter in the middle is the British way. the electrical symbols are different for tea and biscuit eaters as well. its good to know both systems.

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 1:08 am
by tuffteef
i have hit another wall
so if not unit is giving it will be nF?
such as the 4u7 being 4.7nF and in mF it would 0.0047mf? do these come in electrolytic?

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 1:18 am
by Jero
tuffteef wrote:i have hit another wall
so if not unit is giving it will be nF?
such as the 4u7 being 4.7nF and in mF it would 0.0047mf? do these come in electrolytic?

Damn it tuff, I had to read that like 3 times to understand what you said :lol:
"4u7" is likely 4.7uf, not nf.

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 1:24 am
by tuffteef
Jero wrote:
tuffteef wrote:i have hit another wall
so if not unit is giving it will be nF?
such as the 4u7 being 4.7nF and in mF it would 0.0047mf? do these come in electrolytic?

Damn it tuff, I had to read that like 3 times to understand what you said :lol:
"4u7" is likely 4.7uf, not nf.



OHHHHHH I GET IT NOW LOL
just had a duh moment
the letter in the middle u or n means uf or nf
4n7 = 4.7nF and 4u7 is 4.7uf

i knew this right i knew this :idk: tell me i did

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 1:27 am
by McSpunckle
You got it!

BANANA STICKER!

Image

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 1:34 am
by eatyourguitar
Image

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 2:29 am
by tuffteef
McSpunckle wrote:You got it!

BANANA STICKER!

Image



lulz ily :lol:

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 10:02 am
by MEC
For the record Small Bear seems to be the most confusing place to order Caps. The labeling/numbering system he uses makes no sense and is inconsistent.
But I still order from him more times than not. :idk:

Re: Capacitor Units mF uF confusion

Posted: Sun Apr 03, 2011 10:17 am
by McSpunckle
Usually film caps are listed in uF and ceramic are listed as pF. You see a lot of .001uF film caps (which would make more sense as 1nF), and 3900pF ceramic caps (3.9nf, .0039uF). It's weird how they do that, but it makes a bit of sense when you consider that most ceramic caps are smaller values, and film caps are kinda mid-range.

Either way, once you know how to convert them, it's not a big deal.