0 ohm resistor

I'm not very bright, so I can't think of a reason for a 0 ohm resistor. What are they for?

Mark Frauenfelder is the founder of Boing Boing and the editor-in-chief of MAKE and Cool Tools. Twitter: @frauenfelder. Come and hear Mark speak at the ALA conference in Chicago on July 1.

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The Snowden Principle

Rob Feldner

Resistance is futile.
- http://profiles.google.com/murso74 Matthew Urso
  
  thanks for that
- http://twitter.com/ChristineKeele1 Christine Keeler
  
  Very good. I bow in ohmage to you.
  - CpnCodpiece
    
    Watt?
    - awjt
      
      Jeez. These puns are reVOLTing.
      - Roberto De Almeida
        
        What can I say?, it’s the current trend…
      - http://mordicai.livejournal.com Mordicai
        
        I’m galvanized into action; we have to take a stand against it.
      - dpedneault
        
        Power to the people!
    - http://twitter.com/WeirdCoolDumb Weird Cool Dumb
      
      Too many puns! Wire y’all doing this?
      - http://twitter.com/ScissorNightRam Lennoxx Bllaze Wesst
        
        My opinion? I’m polarised by this battery of puns – I can see both the positive and negative of this charged issue.
      - Brett Miller
        
        Don’t stop! I’m AMPed for more!
      - http://www.xradiograph.com/ OtherMichael
        
        There’s something circuitous about this logic.
- http://twitter.com/openfly ǝɔʎoſ ʇʇɐW
  
  Oh god… don’t divide it by zero. STAY AWAY FROM OHM’S LAW!!!
- Benjamin Fryc
  
  Lorem Ipsohm
- Jimmy Crashbox
  
  Nope, Resistance is Voltage divided by current my friend.
Jupiter BFPOE

I believe they are used in electric left handed bacon stretchers.
- http://eagleapex.com eagleapex
  
  You beat me to it.
http://www.flickr.com/photos/stefan_e_jones/ Stefan Jones

Testing purposes, perhaps?
Offlogic

They make good programming jumpers. I tend to stick them into prototype boards to isolate sub-circuits for troubleshooting (ever tried to find the short on a power plane?).
retchdog

placeholders for a fixed wiring diagram/breadboard? e.g. you replace an adjacent component with one with higher X more ohms, you can just replace the X-ohm resistor with a 0-ohm resistor? can’t think of situations where this would be easier than a wire, but maybe it’s a mnemonic device? like, “hey, you might have to change this piece later.”
http://twitter.com/poeslacker poeslacker

Imagine you had a pick and place machine installing resistors in a circuit board. This board can be configured in a couple of different ways, and
- http://glitch.tl/ Michael Smith
  
  Yes and if you need a link between two tracks, the machine can place a resistor there easier than a length of bare wire.
- Pag
  
  Don’t you it when your comment’s cut off? I always feel like
  - http://twitter.com/mondongo90210 Mondongo
    
    What do you meaALL GLORY TO THE HYPNOTOAD
  - John Vance
    
    Can’t tell if Candlejack thread or hypnoto
    - oasisob1
      
      I
      - Scratcheee
        
        That’s too
    - Ian Anthony
      
      Dude, this isn’t 4chan. You can’t just
      - http://twitter.com/openfly ǝɔʎoſ ʇʇɐW
        
        How to triforce?
      - http://www.xradiograph.com/ OtherMichael
        
        How is 0-ohm resistor formed?
chrisspurgeon

Like poeslacker began to say (his comment is truncated for me) they are often used to connect different parts of a circuit board. Since they are the same size and shape as other resistors, automated “pick and place” machines can place them like any other resistor.
- http://www.gyrofrog.com/ Gyrofrog
  
  That’s how I remember it (though these were tiny little surface-mount resistors).
Francis Altomare

to be used as a link between points on a pcb
James Jurack

poeslacker, you’re right on the money. The board I’m currently writing firmware for (and several others before it) use them in just such a fashion. Though I admit, they make way more sense as SMC than as through-hole. If you’ve got holes and wires already, why not just use a piece of wire?
- Guy Dawson
  
  The pick and place machine has a picker that is designed to pick up a resistor. As wires don’t have the same geometry it’s easier to change the wire into a resistor than provide the machine with two pickers.
  
  A production line with need either a machine with a second pick arm, interchangeable pickers or a second machine.
  
  Wires with little lumps on to make a zero ohm resistor then make commercial sense!
  - Buelah Man
    
    TDK once manufactured a thru hole Axial inserter (the Avisert) that could handle both components and wires only. So did Universal.
Matthew Siegler

I use them extensively in my rare-earth magnet powered perpetual motion machines. Alas you need the ones with no oxide-type diode effect.
- spejic
  
  If you replaced them with a -1 ohm resistor, you’d get above unity on your device.
  - http://www.appliedesoterics.com bfarn
    
    You two better snatch ‘em up quick before anyone else catches on!
    
    (sorry, couldn’t help myself)
peterkvt80

In automated board stuffing a machine can handle a resistor better than it can wire links. In surface mount 0 ohms is often used for connecting optional circuitry.
- John Vance
  
  Do pick-and-place systems work with through-hole components, though?
  - http://www.gyrofrog.com/ Gyrofrog
    
    I know they used to, but as someone else mentioned, it could just as easily place a length of (bare) wire.
  - Buelah Man
    
    Yes. Altho the technology is BIG and old, they still make them. Universal and TDK both have these types of machines in the field.
fuzzyfuzzyfungus

They can be used as jumpers; but mechanically identical to the other resistors being installed on the board, for greater efficiency. Also available in SMT form.

I’m a little more surprised to see them packaged in what looks like such a small quantity, since the ‘mechanically identical’ thing matters more with a pick and place than it does with manual work(where dropping in a piece of wire is not a big deal); but I suppose that almost anything that comes in reels of a zillion has somebody who will cut 50 off the reel for you.
stcorbett

perpetual motion and zero point energy
voiceinthedistance

Everything sounds better in French: zéro de résistance

Perhaps we should ask Joe, because “Joe Knows”™
http://twitter.com/digitalArtform Joseph Francis

I forgot my mantra!
- perchecreek
  
  Ohm mani padme ohm
http://twitter.com/Bashtarle Bashtarle

I have heard people use them to make their boards look more presentable. Probably for demonstration purposes to people who don’t know what they are.

Ask yourself what looks better, a component that for all intents and purposes is a piece of wire or a piece of wire? Once you get the greenlight from a suit who doesn’t know any better just slap some wire in there. The end consumer is likely never going to see it anyhow :P
http://avarana.blogspot.com MarlboroTestMonkey7

Because common wire might offer some infinitesimal resistance you don’t know about
- Bobby Martin
  
  Yeah, this was aching for a room temperature superconductor comment.
  - billstewart
    
    Cool! Somebody got there before I did!
http://www.facebook.com/rzazueta Rob Zazueta

I just assumed they were there to make your Ohm’s Law calculations more interesting.
- Nylund
  
  To infinity and beyond!
http://twitter.com/onthemasspike Tiffany

Connections in areas of a circuit/chip that are similar to the physical characteristics (spacing size) of the resistor.
Jeffrey Rodman

A circuit design will often find component values changed for various reasons, either during bringup (oops, that should have been connected straight across), or to build a different version (think of a circuit board that is sold as two models with two different op amp gains), as part of a test process (test the board in one mode, then clip or install the resistor to ship), or during its lifetime (such as compensating for another component that drifts in value). Sometimes that value will change to zero. Because the zero-ohm resistor is still, physically, a resistor, it fits in the same holes (or if it’s a surface-mount zero-ohm resistor, on the same pads), will still be compatible if the board is being assembled by an automatic machine, and it doesn’t risk shorting out any traces beneath.
- http://thisisonlya.blogspot.com robcat2075
  
  How is it that an almost entirely exposed length of conducting material “doesn’t risk shorting out any traces beneath”
cdh1971

I clicked on comments to write something, but I was beat to it by multiple commenters.

However, I didn’t know they were used for the purpose described by peterkvt80.

Pretty cool – and Mr. F – I bet you not only knew the function of these b4 posting about 0-ohm resistors, I bet you’ve used them before ;)
fpp2002

They act as jumpers, and can be used to configure a PCB in a variety of ways. For example, if daughterboard A is attached, then populate the jumper position with a 0 ohm resistor. If daughterboard B is used, don’t install the resistor. These resistors can be run through a lead bending machine just like a regular resistor, rather than requiring a special tool to handle just bare jumper wires. A better way to do this would be to have two square surface mount pads about 10 microns apart, and you just create a solder bridge across them.
Taniwha

As others have said they’re jumpers – you put them in the power circuit on a proto so you can drop an ammeter in there to measure power draw, and so you can bring up sub circuits one by one, you put them in as stuffing options to program modes on chips (like boot modes on CPUs). On single layer boards you use them for routing
http://www.facebook.com/brushyfork23 Michael Black

Jumpers! I’ve used them before as a physical device for making two PCBs stand off each other at a consistent length.
Anaerin

That’s easy. You use them as voltage limiters for your Signetics write-only memory: http://www2.vmi.edu/Faculty/squirejc/Research/IC_Datasheets/digital_cmos/Write%20Only%20Memory.pdf
- http://twitter.com/woulfejh Justin Woulfe
  
  Rah VA Mil!
http://lemoutan.blogspot.com/ Lemoutan

Well they’re for infinite power of course. Just supply a voltage and there y’go.
- malindrome
  
  You have to be very careful with those – infinite power corrupts infinitely.
  - http://lemoutan.blogspot.com/ Lemoutan
    
    Now you have me wondering if power be the only noun which, adjectived, corrupts corresponding-adverb-ially?
    - kinscore
      
      Did you mean adjective noun verbs adjectively?
      Simple example exemplifies simply?
      No, wait, corrupt is invariant, not based on the noun…
      Magnetic memory corrupts magnetically?
      Not a great one, but maybe it will get something started.
      - http://lemoutan.blogspot.com/ Lemoutan
        
        I was content with the malindromic fixed points of power and corruption, since it seemed to convey something useful. But now you mention it, fastforwarding to magnetic magnet magnetises magnetically is rather trippy.
- kraken17
  
  Sure, but try finding the ones rated for infinite wattage. Thanks for nothing, Digi-key!
adralien

They are used often in single-sided board layout if you run into an impossible corner to route without jumpers. A few 0 ohm jumpers is less expensive than a 2nd side of copper to solve the routing issue. Old stereo amps have lots of these.

They are used less for that purpose in SMT designs, as newer designs are usually double-sided or have internal copper layers for solving routing issues. Since they are used less in SMT, the SMT versions are quite expensive compared to normal resistors. If you need a SMT jumper, and you can electrically use a small resistance (1R or 10R) instead of 0R, it is preferable.
xzzy

You just got pranked, the bag clearly states they are from “joek now selectronics”.

At their website the prankster fills out a personality profile of the intended target, which the site uses to generate the most hilarious prank (in this case, getting someone to wonder to as wide an audience as possible what use a 0 ohm resistor has).
nomad411

From Wikipedia: A zero-ohm link or zero-ohm resistor is a wire link used to connect traces on a printed circuit board that is packaged in the same format as a resistor. This format allows it to be placed on the circuit board using the same automated equipment used to place other resistors instead of requiring a separate machine to install a jumper or other wire. Zero-ohm resistors may be packaged like cylindrical resistors, or like surface-mount resistors.
morcheeba

Make sure you get the +/- 1% tolerance resistors; the 10% tolerance resistors are much worse ;-)
- bcsizemo
  
  I don’t even see a tolerance band…
http://profiles.google.com/stephen.schenck Stephen Schenck

I wouldn’t put it past audiophiles trying to use them in place of speaker wire or other interconnects.
- http://www.edmstudio.com futnuh
  
  Gold-plated, of course.
- Xof
  
  Oh, man, you can’t use standard 0 Ohm resistors. You need the special ones that are $25 apiece. The difference in the expansiveness of the sound is amazing.
  - RichG2012
    
    Yeah I got a USB microphone, and I paid extra to make sure it came with a gold plated USB cable. :) Otherwise the sound would be attenuated.
    - Xof
      
      I did have someone at Radio Shack attempt to sell me an HDMI cable with gold-plated connectors once, as being far superior to a boring old normal HDMI cable.
oldtaku

In addition to the other comments, we also use them where there’s a possibility we might want to open the circuit in the future – snipping out one of these is cleaner than cutting a trace. And it’s cheaper than a jumper.
Nic Seymour-Smith

Useful for “multi-purpose” design boards. e.g. you get a batch of 50 pcbs for photodiode amplifiers made for you, and depending on whether you want your particular photodiode input ac coupled or dc coupled, you can either put a capacitor or a 0 ohm resistor in! Neat!
John Stilley

Am I the only one bothered by “zero” Ohms?

I want a zero Ohm resistor! We can build no-loss power grids by chaining them together. The future is now.

(I bet they are 0.49 Ohm resistors.)
- bcsizemo
  
  Unlikely. 1/2 ohm is still a fair amount of resistance depending on the circuit design. I’d imagine they are nothing more than straight wire with the ceramic baked on. But for the typical uses a 1/2 ohm resistor probably would be acceptable.
Joshua Brown

http://en.wikipedia.org/wiki/Zero-ohm_link
http://twitter.com/smknghrtdesigns SmokingHeartDesigns

FUSE
- https://plus.google.com/104067355242126774300/posts?hl=en Dennis Smith
  
  Has been known. Some of the boards I’ve worked on have used a Zero Ohm resister of a specific wattage to act as a fuse.
- francoisroux
  
  Yes, was just scanning the comments because invariably someone would have given the right answer already, or a right answer anyway. A 0 ohm resistor would burn out/of quicker than a wire jumper and is easier to make for a certain wattage. Si it could be used as a first line fuse-able part to protect a circuit.
Dave Nelson

What’s really cool is that the 0 Ohm “resistors” are rated 5%, 1/4 watt!
doniphon

They’re going to need a whole lot more of them now – there are two in every Boson.
ozzythaman

of course they are NOT zero ohm transistors…. perhaps zero point something… but ZERO would mean NO resistance whatsoever… in other words a superconductor and even better. just rounded to zero i would say..
Bill Higgins– Beam Jockey

Personally, I find them irresistible.
ludd

Used to test “Placebo Effect”.
http://www.facebook.com/people/Flugfrei-Jones/1403604860 Flugfrei Jones

bunch of these and some smoothing caps and you can really make your blinky LED circuit look fancy.
http://profile.yahoo.com/NB5F7GHWTNWIXEJILSR3H6GIQU zibuki

” I’m not very bright…” Wow. Please don’t ever say anything like that about yourself.
http://disqus.com/Kimmoth/ Kimmo

They’re a novelty gift for electronic engineers.
Neo Displacer

I’ve only seen these in the wild once. There were used as a jumper on a timer relay. Clipping them changed the behavior of the timer. I cannot tell you why header pins and a jumper or better yet a switch was not used. Maybe the guy laying out the board thought 0 ohm resistors were cool.
randigomboc

Obviously these use quantum effects or are super conductor based etc. as everybody knows that copper wire even this short can’t be zero ohms and always has some resitance! :)
bcsizemo

Don’t you get a 0 F capacitor when you leave the 0 ohm resistor out?
jeligula

Jumpers and circuit isolation. They also work for baselines, if such is your desire. My brother uses them all the time for jumping without breaking the circuit, but he is pretty sneaky about what he does, most of it either not legal or circumventing the designer’s intended purpose.
http://twitter.com/chrisjimson chris jimson

It’s a zen thing. Chant “ohm” for a while and you’ll understand.
http://www.PatentekLLC.com LV

Looks like more stealth inflation. Some day you won’t see jumper wires in stores – just really well-conducting resistors.
http://profile.yahoo.com/VEGTWWYYHIDUUSPWHSCVEDQEMM RÜFÜS

I’ve designed hundreds of boards and have included 0-ohm resisters for many reasons. They are mainly used as “jumpers” where, for instance you may want to test each part of a circuit separately, or possibly use these to set feature options in the factory (though mostly this is now done in software). Rarely do they show up in production assemblies anymore, since they cost a few cents each to insert, and that can add up to several boat payments if you’re selling a lot of widgets.
http://profile.yahoo.com/65CSAR3QATRNKJW4NYNB2BESZE JohnQPublic

it’s so it looks complicated when you present your project to the management team with the liberal arts degrees.
Snig

I think they’re the electronic equivalent of lingerie. Often employed to create only a hint of impedance but actually offering exceedingly minimal resistance.
Jefferson Preston

They be programming jumpers. Clipping them changes the routing.
http://www.facebook.com/profile.php?id=1224458082 ElAndrés H Mino

o ohms are good for bread boards using surface mount components, but for a proto-board using through-hole components??? seems like a wire would suffice until you value to precisely tune your circuit (and you could even measure the impedance of the wire if you wanted to be really anal about it)
BarBarSeven

I think it’s an ironic promo piece for the next Wes Anderson flick.
http://synerdata.net/ Gordon Stark

Because oxi-morons sometimes need to fix electronics?
http://redesigned.com redesigned

you can also use them as bi-directional diodes…

…which is a joke except there actually is such a thing for AC circuits known as DIAC/TRIAC.
Dave Nelson

I don’t really see what the great mystery is. I use them all the time to allow different circuit configurations, by simply adding, removing, or changing the value of surface mount 0 Ohm resistors. Works great.
Mac

They are also a good substitute for Infinite Farad capacitors or zero Henry inductors.
simonbarsinister

You should try magnetic monopoles instead of rare-earth magnets in your perpetual motion machine. I used them in my Time Cube (google it) and got great results.
http://twitter.com/grimmtooth grimmtooth

The most common use of zero-ohm resistors I have encountered is as a substitute for a ferrite.

A ferrite is a bit of wire that runs through a ferrous block of material. One much larger example is that little lump on the power cord of your monitor (not all have one).

Its purpose is to supress RF emissions from coupling to a potential antenna, such as a long bit of cable close by or whatnot.

This sort of thing is needed to ensure that the device it is in passes FCC / EU / etc regulations for radiated emissions.

The board is initially designed with maximum suppression components - suppression ferrites, coils, and decoupling capacitors. At some point, they start removing suppression components. The caps, they just remove. The coils and ferrites, however, are in-line and have to be replaced with something. Say hello to zero-ohm resistors.

Why don’t they just redesign the board without those components? Because spinning a new board ain’t cheap. Because the enclosure’s configuration might change, causing a need for those components. Because … testing is never absolute. Tons of reasons. Bottom line is that a bunch of SMC components are prett cheap. Redesigns are not.
TelmeaStory

Bad beer rots our young guts but vodka goes well – get some now
WhyBother

It’s already been mentioned that you can use these as shorts which are friendly with pick-and-place machines. An extension of this is that some through-hole parts are used to connect separate parts of the board, even if the rest of the components are surface mount: you don’t want to waste money on superfluous PCB layers, so if you just need a single trace on “layer 3″ to make the routing work, you find some length of trace that can be absorbed into/replaced by a through-hole part.

It’s also been mentioned that 0 Ohm resistances are used all the time a configuration jumpers. Mostly this means digital configurations, where a path is either open or closed, but it can also mean down- or upgrading analog components. For example, a five-stage filter could be converted into a three-stage filter with the same PCB layout, and different population options. Just use NP (non-pop) and 0 Ohm components to replace the components that are no longer mathematically necessary.

On completely surface mount board, you still might want 0 Ohm chip resistors for similar reasons (opening or closing optional paths). This is also sometimes done by using a chevron pattern that you can easily lay a blob of solder across to create a short. The chip resistor is generally easier and more reliable, however, because it is easier to solder down the two pads of a chip resistor by hand than try to bridge a gap with solder directly, and using a chip reduces the chance of a cold solder joint that would increase the resistance. Not to mention that if the solder blob is supposed to be closed by default, it’s easier for a machine to accomplish by laying down a chip.
http://www.facebook.com/niksgarage Nick Sargeant

Why is there no tolerance band on these resistors? I’d want to know if they were 1,2 or 5% ..
Daemonworks

You could make jewelry out of them…
tommickx

Back in the days when I built my own amps and things, I used them for aesthetic reasons. A bunch of resistors all lined up parallel to each other looks way neater than resistors mixed with wire jumpers. (I usually made single layer PCBs, so there’d usually be a couple of jumpers.)
Of course I only used them because I had a big bag full of them from a local electronics junk yard.
David Perriman

Safety resistors? Although they are normally a slightly higher token value.
benher

Why? For all the completionists of course!
retepslluerb

Simple. You take a 1 Ohm resistor, put a 0 Ohm resister behind it and you get a 10 Ohm resistor.

Or does it work in binary? It’s been a while.
robuluz

Wow. Now I know what a zero ohm resistor is for, 100 times over.
John McGaw

Simple jumpers used to bridge over other traces on a printed circuit board. They are in effect wires but wires that can be stuffed by the automatic pick-and-place machines.
robuluz

101 times.
TheDaleks

Zero ohms proves that resistance is futile.
psiwar

I=V/R
OSHI–
Atvaark

Crisis. People can’t afford their ohms anymore.
Douglas Rushkoff

Of course, they’re not really zero ohms. Should probably be called “approaching zero ohms.”
traalfaz

They’re jumpers that are compatible with pick-and-place machines. You can get them in surface mount as well.
http://twitter.com/wilmcdaniel wilmcdaniel

I got nothin.
Adrian Beta

One does not simply use a 0 ohm resistor
SignalJammer

These came out at at a certain time in a big way. I think that there is this fearsome moment when design hands a PCB to the suits. They can only look at it and criticize its aesthetics. At the same time the suits ended a practice of putting in lands and foils for ‘ghost’ components that would make the board much more longer-lived by making it more general. The suits presumed the clients would see empty component screens and presume they were getting cheated out of something. So sad. . .
Trygve Trohaug

They are use in place of jumpers when a robot assembles circuits. It saves time because the robot doesn’t have to stop and change tool.
http://www.acmedigital.com ebiii

Best comment thread I’ve read in a long time, lots of wit and new information. But why do we always have to jump on the audiophiles? Have some compassion. Inter-connects are expensive! Especially when they’re not paperclips. Please don’t bring all that attitude to the next listening party, you’ll flatten the soundstage and etch the highs.
http://www.facebook.com/people/Vincent-Amatrano/100001369910652 Vincent Amatrano

The zero ohm resistor is used for series parallel circuits involving anti electrons in calculators so you can divide by zero
sqyntz

zero ohms? hmm, so these are superconductors?
- jnordb
  
  No…the resistors themselves are zero ohms, but the leads still have minute amounts of resistance.
wade staggs

I can’t find a good Zero Ohm Resistor! My meter says that every one of them at my shop are Dead Shorted. All jokes aside, I once gave a New Tech a Make Work Job of Checking about 5,000 Four Amp Fuses. Went back to check on him at break time and he had placed every one that he had checked in the defective box. He sais that they were all Shorted. This guy didn’t last long at Scientific Atlanta!
http://www.facebook.com/people/Richard-Corso/1482714027 Richard Corso

Zero Ohm resistors are used in the triple sprocket gudgen clutch analyser and also require two foofoo tubes.
If anyone’s interested I have several minus one ohm resistors for sale :-)
ludwigk

Is there anything in a 0 ohm resistor? Wouldn’t you just place regular wire with a bit of casing around it?
nemryn

Magic!
SignalJammer

As an ‘op amp guy’ I’d rather have to discuss these with the lay community than FDNRs and gyrators!
http://profile.yahoo.com/OMHO6ER5QJE3SIZ35VAXIRCLYM Stephan

Ohm sweet Ohm! (Kraftwerk)
gypsydoctor

Do they also make infinity ohm resistors?
- http://www.facebook.com/ron.sonntag Ron Sonntag
  
  Yes. Broken wire, blown fuse, bad solder joint, missing line, etc.
  - Henrik Lans
    
    Actually, a 0-ohm resistor (or a resistor of any value) can easily be converted to infinity-ohms; just use your favourite tin snips and cut the resistor in half; then mount the two halves facing away from each other?
terrycarroll

This is why I like BoingBoing. I’m a former English major. I lurk in the corner and absorb science. From the very posting of Mark’s question, through this string of comments — including, especially the jokes (because jokes require understanding what is false) — I’ve learned some sort of fundamental knowledge about resistors. They are objects I’ve seen on every circuit board I’ve ever handled … as a consumer. But until half-an-hour ago, I couldn’t tell you even what they were. Thanks!
http://twitter.com/qazwart David Weintraub

I use these all the time in my superconducting circuits.
http://twitter.com/GenesisMachines Glen Searle

Room temperature superconductor.
MarcVader

Actually… they’re used in self-sealing stem bolts and reverse-ratcheting routing planers, duh!
http://twitter.com/Catarino Catarino™

The only sane reason for that… http://memegenerator.net/instance/23151290
merck

These are also used in prototyping. If you think there may be an emc problem that might need a capacitor or inductor later on, it is easier to design it with a 0 ohm resistor so you have the footprint ready on the board. Then it is as simple as removing the resistor and replacing it with another part.
jnordb

If you connect two or more of them in parallel, you get a negative resistance value – it’s how superconductors are made.
http://www.facebook.com/ron.sonntag Ron Sonntag

Profit!
Michael Woudenberg

http://en.wikipedia.org/wiki/Zero-ohm_link
Henrik Lans

In a project I’m currently working on, I needed to daisy-chain two small driver cards in an I2C-bus. Due to space constraints in my mounting box, I decided to mount one above the other; and using 0-ohm resistors as spacers worked out nicely – much better than bare wire. Thanks to Evil Mad Scientist Labs, I had a couple lying around – they use them as options in some of their kits.
nigex

I’m old enough to remember these were used as links on cheapie circuit boards. Single-sided boards are cheaper, but sometimes you need to link two tracks together when some other tracks are in the way. So you put a zero-ohm link in!
As people have said, component placers were able to put resistors in, but often they couldn’t do wires.
What confuses me is that when you buy surface mount ones, they’re often described as, say, 125mW 0R 0805′s. But if there’s no resistance, how come they only cope with 125mW?
Sorry for lack of puns.
http://twitter.com/Listener43 Listener43

Zero ohm resistors are nice enough, I suppose, but I prefer the -1 ohm parts for my builds.
Martin Boulter

They actually serve a few purposes, simple bridge just like a wire jumper, fuse as they can typically only hold a certain wattage, but most commonly they are used for tuning circuts. This is especially common in wireless networking, LED displays, etc… where timing matters. So they can add or remove latency in the circut.
Ryan Lenethen

Electronic Placebo…