Oxymoronic 0 Ohm resistors

[EvilGeniusSkis]

I understand the usage of SMT 0Rs, but I do not see the point of 0R TH resistors; wouldn't a bit of wire be cheaper.
 

[McBryce]

If you can get a pick and place machine to place the wire yes, but a wire that needs to be manually inserted will costs more.

McBryce.

[cowana]

As component cost, yes.

However, assembly companies are already fully setup for automated unpacking, bending and preparing resistors for population, so a 0R resistor is no different. Using a small piece of wire would not be possible using the resistor lead-forming equipment - it would have to manually be cut to length, stripped, bent...

So the answer is that a 0R resistor is cheaper when you factor in the assembly time.

[AndyC_772]

Hands up who has ever been asked whether a 0R resistor should be 1% tolerance or 5%.

 

[McBryce]

Hands up who has ever been asked whether a 0R resistor should be 1% tolerance or 5%.

 

So what's 5% of 0? And wouldn't I need to keep them at absolute zero for them to be accurate at all?

McBryce.

[madires]

Hands up who has ever been asked whether a 0R resistor should be 1% tolerance or 5%.

If you got a milliohm meter with 4-wire/kelvin probes you would find out that the 0R resistor got a few milliohms. There must be something very wrong 

[sleemanj]

I understand the usage of SMT 0Rs, but I do not see the point of 0R TH resistors; wouldn't a bit of wire be cheaper.

I use 0R through hole all the time when doing single sided homemade boards, especially if the board is intended for copper-side-up

it's easier than cutting and bending solid wire
It's tidier than stranded wire jumpers
It's faster than stripping enamel coated wire
the "resistor" body holds the legs off the board so they won't short to the copper traces underneath
top-side-soldering them looks much nicer for copper-side-up boards (ie surface mount buttons etc) than having solder tails sticking up at you from bottom side jumper wires

I use 1206 as well when i only need to cross one trace.

In industry it's more about already having machinery to handle resistors, so two birds with one stone.

[free_electron]

Hands up who has ever been asked whether a 0R resistor should be 1% tolerance or 5%.

 

real men use temperature compensated, oil filled,  0.001% 0 ohm resistors and wire them in kelvin configuration on teflon standoffs. !

[Delta]

Standby for my Kickstarter - "Graphene constructed, cryogenically quantum treated, audiophile grade zero Ohm resistors".

[SeanB]

The only time I have seen machine inserted wire links is in copiers and printers, where they will do wire links, either to use a single sided SRBP board ( cheap and can be made either additively using a screen printing process, or which can be etched fast) and up to 300 wire links, or on a double sided board so as to avoid having to use a multilayer board, but still having a ground plane on the board for EMI reduction. There they also often did the board as double sided but without through hole plating, using the component leads and links as connections to the top side traces. Top side was hand soldered as well with the bottom being wave soldered.

Saw a Sharp copier board with literally a single mask MCU, a decoupling capacitor, a crystal and 2 capacitors and a quartet of components for reset, and 300 wire links in neat rows across the board, in 2 orientations and 4 different lengths. All this and around 11 multipin connectors to the rest of the machine. You might have up to 10 wire links on a single trace, from one connector and going to another. All this to use a single sided board. It must have been cheaper than going double sided through hole plated by at least a few cents.

[mazurov]

Resistors are cheaper than wire these days. You buy a thousand Chinese LEDs on eBay,  you get a thousand of shitty Chinese resistors of some value as a bonus. I have a bottomless bag of those on the bench to cut the legs off of when I need a piece of tinned wire to short something together.

[xrunner]

If it's Zero ohms ... then it ain't a resistor 'cause it ain't resistin' anything. 

[Neilm]

There is a datasheet for a series of resistors that we have at work. Part of the spec states something along the lines of "+/- 1% +/- 10mohm" for values less than 1 ohm. I haven't yet seen any of the "Zero ohm links" that are in the range with a negative resistance.

[free_electron]

Standby for my Kickstarter - "Graphene constructed, cryogenically quantum treated, audiophile grade zero Ohm resistors".

made from old coathangers. cause they sound the best. especially if they were used to hang woolen clothes. stay away from coathangers that were used for synthetic fibers. those are only good to play kraftwerk music,

[Psi]

It's really interesting when you get a +/- 1%  0 ohms resister in the left side of the bell curve 

[McBryce]

Standby for my Kickstarter - "Graphene constructed, cryogenically quantum treated, audiophile grade zero Ohm resistors".

Shut up and take my money!!! Where do I make my pledge!? Will you be goldplating any and all visible metal on them? Does it come in a hand carved presentation box?   
This would be perfect for discharging those Audio Grade Capacitors I bought for €8K last week.

McBryce.

[mikeselectricstuff]

Hands up who has ever been asked whether a 0R resistor should be 1% tolerance or 5%.

 

Both are available....
http://uk.farnell.com/multicomp/mcf-0-25w-0r/resistor-carbon-film-0r-0-25w/dp/9339027
http://uk.farnell.com/vishay-bc-components/mba02040z0000zrp00/thin-film-resistor/dp/1772532

[SeanB]

So basically they give you a untrimmed resistor when you select a 0R option, using the film that they put on the lowest value ( 1R for the MCF, 0R22 for the Vishay) and not trimming it, so it will only have a maximum limit value of 1R or 0R22. Actual value will be batch dependant, and position in the batch as well. At least you can be sure they will be non inductive though.......

[Jope]

So basically they give you a untrimmed resistor when you select a 0R option, using the film that they put on the lowest value ( 1R for the MCF, 0R22 for the Vishay) and not trimming it, so it will only have a maximum limit value of 1R or 0R22. Actual value will be batch dependant, and position in the batch as well. At least you can be sure they will be non inductive though.......

No. Farnell just goofed up on the description. Take a look at the manufacturer code of the Vishay 0-Ohm resistor (MBA02040Z0000ZRP00) and at the datasheet. The Z means 'jumper', with a resistance of >= 10mOhms, according to datasheet.

[sunnyhighway]

The Z means 'jumper', with a resistance of >= 10mOhms, according to datasheet.

So that resistor would have a precision of ?%
Not sure what color that ring would be... 

[EvilGeniusSkis]

Thanks to everyone who explained the use of 0R TH resistors, now here's my comedy piece: "Join the resistance and help us reduce our mortal enemy, the current!"