Sequence of the colors in resistor - Page 1
Forum section: electronics / beginners

author: Jasonbit
author_rank: Regular Contributor
timestamp: October 01, 2020, 08:20:12 am
content: Hello,This situation is it possible? (please see the image number 1)Or only exist this sequence colors? (please see the image number 2)Thanks

author: Zero999
author_rank: Super Contributor
timestamp: October 01, 2020, 08:28:24 am
content: It's theoretically correct, but in practise resistor values don't have leading zeros, because it compromises precision, so you'll see #1 but not #2.

author: Jasonbit
author_rank: Regular Contributor
timestamp: October 01, 2020, 09:05:19 am
content: Quote from: Zero999 on October 01, 2020, 08:28:24 amMaybe did you mean to say image #2.PNG it's correct, right?I can't understand what do you mean in this part "...because it compromises precision...". Can you explain more this part?Thanks

author: Gyro
author_rank: Super Contributor
timestamp: October 01, 2020, 09:12:46 am
content: No, image #1 is correct. You will never see a resistor with a leading zero colour band, it is redundant information. The multiplier ring would be changed to avoid this situation.Eg. How would you represent 2.2k (what Zero999 describes as precision) with a zero as the first band.

author: Brumby
author_rank: Unknown
timestamp: October 01, 2020, 10:54:32 am
content: Quote from: Gyro on October 01, 2020, 09:12:46 amThis ^ ^ ^ ^You don't normally write numbers as 01, 002, 0003, 00004, etc. since the leading zeroes tell you nothing - and when you only have a limited number of bands, you aren't going to waste them on something that provides no information.According to the schema, image #2 does define a value - but just because it does, does NOT mean it will get used. And, to be perfectly clear, it is NOT used.A similar argument applies to writing a number as 2345678.90E+09 While itismathematically unambiguous, you just don't do that.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: October 01, 2020, 11:28:36 am
content: I think there is some confusion because image "2.png" is shown first on the forum.Now do the same with a 4700Ohm resistor.These usually have 47E2 = Yellow, Purple, Red.Your other way around would be: 047E2 = Black, Yellow, Purple, Red. Which needs 4 color bands, and the leading zero has no significance at all.Then there is also the information that is conveyed in the number of bands.4 band resistors (with tolerance ring) are pretty much standard and most often from the E12 range.With more bands you expect E24 or better, tighter tolerances, special properties such as temperature coefficients etc.

author: Zero999
author_rank: Super Contributor
timestamp: October 01, 2020, 12:15:27 pm
content: Quote from: Doctorandus_P on October 01, 2020, 11:28:36 amThat's true.To clarify. The first image attached to the original post, "2.png" is correct.

author: Jasonbit
author_rank: Regular Contributor
timestamp: October 01, 2020, 01:05:45 pm
content: Thank to clarify the issues of the images. To simplify I write the number on the images (please see all attached).On this website we can see all values on serie E12 and respective representation of the colors on the resistor body:https://www.hobby-hour.com/electronics/e12-resistor-color-code-examples.phpThanks to your all replies

author: Zero999
author_rank: Super Contributor
timestamp: October 01, 2020, 01:24:14 pm
content: Quote from: Jasonbit on October 01, 2020, 01:05:45 pmNumber 2.20×100Ω5%= 2k 5% is the correct one.

author: magic
author_rank: Super Contributor
timestamp: October 01, 2020, 02:02:34 pm
content: I wonder how they encode sub-1Ω values in the 5-band system for 1% resistors

author: newbrain
author_rank: Super Contributor
timestamp: October 01, 2020, 02:23:23 pm
content: Quote from: magic on October 01, 2020, 02:02:34 pmif you mean 3 digits + multiplier + tolerance:Pinkas the 4th band means × 10-3, so it allows for values 0.100 Ω to 0.999 Ω.

author: Gyro
author_rank: Super Contributor
timestamp: October 01, 2020, 03:21:22 pm
content: Quote from: Zero999 on October 01, 2020, 12:15:27 pmDoh yes, well spotted. Attachment ordering can be a pain sometimes.

author: ArthurDent
author_rank: Super Contributor
timestamp: October 01, 2020, 03:40:42 pm
content: A little unique is the zero ohm resistor which is a jumper and as a leaded component has just one black band to indicate its value. The reason to use a 0 ohm resistor instead of just a wire jumper is that on commercially made circuit boards these 'resistors' can be placed on the circuit boards with automatic insertion robots.

author: wraper
author_rank: Unknown
timestamp: October 01, 2020, 03:43:07 pm
content: Quote from: Zero999 on October 01, 2020, 08:28:24 amResistors with leading zero do exist. Although they are quite rare and only used for resistances below 0.1 Ohm when you cannot color code the value without leading zero.

author: Zero999
author_rank: Super Contributor
timestamp: October 01, 2020, 06:52:38 pm
content: Quote from: wraper on October 01, 2020, 03:43:07 pmI've never seen that before. Post an example.Colour codes aren't normally used for very low value resistors, which have the value printed on them, with the letter L being used to denote mΩ, so 24L9 = 24.9mΩ and L470 = 470µΩ.

author: wraper
author_rank: Unknown
timestamp: October 01, 2020, 07:45:08 pm
content: Quote from: Zero999 on October 01, 2020, 06:52:38 pmHere is 0.15 Ohm 5 band variant where this is true for <1 Ohm.https://lcsc.com/product-detail/Metal-Film-Resistor-TH_CCO-Chian-Chia-Elec-C209746_C209746.html

author: Zero999
author_rank: Super Contributor
timestamp: October 01, 2020, 09:53:32 pm
content: Quote from: wraper on October 01, 2020, 07:45:08 pmThat looks pretty dodgy to me. There's no reason for using that stupid colour combination. Four bands could have been used, orbrown,green, black,pink,brown, if five are really necessary.

author: wraper
author_rank: Unknown
timestamp: October 01, 2020, 09:58:05 pm
content: Quote from: Zero999 on October 01, 2020, 09:53:32 pmResistors of those series contain E24 and E96 nominals. There is no good reason to make different marking for some of low values.QuoteAnd what's stupid about it, mind to explain? That you for some unknown reason ingrained in your head that the first ring cannot be black?

author: magic
author_rank: Super Contributor
timestamp: October 02, 2020, 04:59:12 am
content: Indeed I could swear that I have already seen resistors with leading zeros and that's why I asked.And now I even found them in my parts box - 0.1Ω, 1%. Black, brown, black, silver, brown.I'm yet to see a resistor using pink, glad to know it's a thing because that would be aeditEven Digikey doesn't know about pink, lol.https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-resistor-color-code

author: wraper
author_rank: Unknown
timestamp: October 02, 2020, 06:08:58 am
content: Pink was introduced in 2016 in IEC 60062:2016 standard. As resistors are not some cutting edge type product which is updated often, I doubt anyone would rush to implement it instead of leading black ring.

author: Zero999
author_rank: Super Contributor
timestamp: October 02, 2020, 12:03:09 pm
content: It seems to be more common than I origionally thought. I don't get the need for leading zeros though. Why use five bands, when four will do?

author: wraper
author_rank: Unknown
timestamp: October 02, 2020, 01:51:03 pm
content: Quote from: Zero999 on October 02, 2020, 12:03:09 pmI'll repeat. Resistors of those series contain E24 andE96 nominals. There is no good reason to make different marking for some of low values.Why would you make inconsistent marking across different values simply to avoid black ring?

author: Zero999
author_rank: Super Contributor
timestamp: October 02, 2020, 03:19:43 pm
content: Quote from: wraper on October 02, 2020, 01:51:03 pmI see your point.QuoteI avoid a black ring by not sitting on any hard objects.

author: Brumby
author_rank: Unknown
timestamp: October 03, 2020, 05:36:13 am
content: I must be living a sheltered life ... I've never come across a resistor with a black first band.

author: KK6IL
author_rank: Regular Contributor
timestamp: October 05, 2020, 11:28:51 pm
content: With the poor coloring on Chinese resistors, I would hate to have to determine if a color band was red, orange, or pink.

author: wraper
author_rank: Unknown
timestamp: October 06, 2020, 01:24:15 am
content: Quote from: KK6IL on October 05, 2020, 11:28:51 pmThere is no issue with their color. However under CFL or LED lighting some colors may appear weird and difficult to distinguish. Also when resistor is subjected to high temperature for a long time rings may change color.

author: Brumby
author_rank: Unknown
timestamp: October 06, 2020, 11:05:01 am
content: From my experience, there is issue with colour on all blue bodied resistors. Why did they pick THAT shade of blue for metal film resistors?