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 Resistor Colour Code.
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 Return to top of page · Post #: 1 · Written at 4:21:15 PM on 24 June 2015.
Zamiac's Gravatar
 Location: Tynong North, VIC
 Member since 9 April 2009
 Member #: 464
 Postcount: 37

Hi,
Can anyone tell me what the different bands on this resistor mean , they go red, black ,black, orange, brown.. The value?
Regards John.

Resistor


 
 Return to top of page · Post #: 2 · Written at 4:48:07 PM on 24 June 2015.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5239

The colours tell you the value of the resistor, only some like wire wound are likely to have a numeric value.

There are charts available to print out showing numbers related to colour: eg red is 2 but it depends where it falls.

Red Red Red would be 2 2 and the third band two zeros =100 so the resistor would be 2200 Ohm.

The code is also found on some capacitors & some resistors have four bands for value. There can also be a gold or silver band & that is the tolerance.

If you are going to fix sets, it is crucial that you come to grips with the code.

So you have red 2; Black 0; Orange 3 Zero's & Brown 1%

200,000 1% Tolerance

Marc


 
 Return to top of page · Post #: 3 · Written at 6:14:24 PM on 24 June 2015.
Zamiac's Gravatar
 Location: Tynong North, VIC
 Member since 9 April 2009
 Member #: 464
 Postcount: 37

Hi Marc,
Thanks for the reply, red, black, orange would be 20K. what I have here is red, black, black, orange, brown , does the extra black band count as another zero, I've not seen that before.
Regards John


 
 Return to top of page · Post #: 4 · Written at 6:18:18 PM on 24 June 2015.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6678

Zamiac,

There are numerous online colour code converters on the web these days, such as this two-way utility:

http://www.hobby-hour.com/electronics/resistorcalculator.php


 
 Return to top of page · Post #: 5 · Written at 10:57:54 PM on 24 June 2015.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7290

I should put one of those things here. It'd have to wait until some other projects are completed though. Also, I'd allow for the 1% tolerance resistors.

Yes, on a five band resistor the first three represent numbers, fourth the multiplier and fifth the tolerance, so your resistor is 200kΩ. You read the bands in the correct order so you're off to a good start. A lot of people get confused with the five band resistors, though a clue is that most manufacturers print them the way yours is, with the tolerance band being a different width. On a four band resistor the bands are closer to one end of the resistor than the other and the bands are read from the end they are all closer to.

The tolerance colour represents what value the resistor actually is to it's declared value and in this case the resistor should be within 1% of 200,000Ω to be considered in good order.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 6 · Written at 8:06:35 AM on 25 June 2015.
Scraps's Gravatar
 Location: Blue Mountains, NSW
 Member since 10 March 2013
 Member #: 1312
 Postcount: 401

There's good apps around for android and iPhone as well. I use Ohms Law and Electrodroid


 
 Return to top of page · Post #: 7 · Written at 10:03:02 AM on 25 June 2015.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5239

One of the things I do as an attempt to stop mates, getting it wrong & as reminder: All but a few wire & reclaimed resistors are stored in order in seed envelopes (more space effective & convenient).

The value and wattage is on the envelope, as is the colour code of what is supposed to be in there.That means that the subliminal kicks in as the resistor is nabbed,the colour band is more likely to be looked at.

Marc


 
 Return to top of page · Post #: 8 · Written at 5:52:51 AM on 26 June 2015.
Wa2ise's avatar
 Location: Oradell, US
 Member since 2 April 2010
 Member #: 643
 Postcount: 830

That looks like a 1% resistor, 3 digits and then a multiplier. 2 0 0 3 = 200 * 10^3 = 200K
The last band is the tolerance


It's sometimes confusing as to which end you start reading, an ohmmeter can help point you to the likely read. Below are the standard values for 1% resistors

And another table showing the values used for various tolerances


 
 Return to top of page · Post #: 9 · Written at 8:48:49 PM on 1 July 2015.
Airzone's Gravatar
 Location: Maclean, NSW
 Member since 30 May 2008
 Member #: 291
 Postcount: 341

Can't you just meter that resistor, or is it open circuit?


 
 Return to top of page · Post #: 10 · Written at 6:07:11 PM on 15 August 2015.
Labrat's avatar
 Location: Penrith, NSW
 Member since 7 April 2012
 Member #: 1128
 Postcount: 368

Not mentioned here are a few things that might be of interest to some.

1. Were there is no tolerance band, the tolerance is +/- 20%

2. On high voltage resistors, the tolerance band is yellow, as gold paint de-rates the its voltage rating.

3. A common colour code on 1930's resistors was the B.E.D. system Body colour = 1st digit.
End colour = 2nd digit. Dot = multiplier.

4. On modern equipment, low value resistors are used as fuses. These are of a flame proof material.

5. On circuit boards using surface mounted components, zero ohm resistors are used as links.

Wayne.


 
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