Years ago I bought some surplus resistors and in one bag there are three different colors of 30.1k resistors. I assume the original users mixed different brands or perhaps different age (era/marking scheme)? But I am not 100% sure.
I have figured out some of the marking codes and I believe that these are all RN55 (with one possibly being a related similar type).
I interpret the markings to mean "C" = 50 ppm, "B" = 0.1%.
However since they are all marked differently and are even different colors I would like to double check with someone who recognizes the marking scheme.
The first type are DARK Blue and are marked:
Line 1: 91637 (From searching datasheets this might be DALE ERC55?)
Line 2: 904H (Perhaps a date code plus "H" = ???)
Line 3: 3012 (30.1k Ohm)
Line 4: BSCJ (I am guessing B = 0.1%, S = Solderable and CJ is a reel/packaging code. It looks like a Dale part number but does not seem to exactly follow current Dale datasheets and is not marked DALE on the body.)
Can you confirm that these are "C" = 50 ppm, "B" = 0.1%?
What is the vendor and series? I assume DALE but not RN55. Perhaps ERC55?
The second type are Light Brown and are marked:
Line 1: DALE
Line 2: 9651J (Date code plus JAN/Joint Army - Navy)
Line 3: RN55C (RN55, "C" = 50 ppm)
Line 4: 3012B (30.1k Ohm, B=0.1%)
So these look like RN55, "C" = 50 ppm, "B" = 0.1% unless I am wrong.
The third type are LIGHT Blue and are marked:
Line 1: P (Does this signify a different brand/vendor?)
Line 2: RN55C (RN55, "C" = 50 ppm)
Line 3: 3012B (30.1k Ohm)
Line 4: B (B=0.1%)
So these look like RN55, "C" = 50 ppm, "B" = 0.1% unless I am wrong.
What does the P signify (different brand)? Why light blue instead of light brown like the second type? (Brand?)
I also would like to figure out the bag of light blue 20k resistors which have four bands for 20k value (Red Black Black Red) and then gap with a "2" printed on the light blue lacquer and then a violet band. Anyone recognize what these might be especially with the little "2" printed between the four value color code bands and then the fifth violet band? I have never seen a little "2" printed on a resistor before like this. At first I thought it was a brand symbol but under the microscope it is a little 2. The fifth band is violet = 0.1%.
So it looks like 1/4W 20.0k 0.1% but what does the "2" mean?
I have figured out some of the marking codes and I believe that these are all RN55 (with one possibly being a related similar type).
I interpret the markings to mean "C" = 50 ppm, "B" = 0.1%.
However since they are all marked differently and are even different colors I would like to double check with someone who recognizes the marking scheme.
The first type are DARK Blue and are marked:
Line 1: 91637 (From searching datasheets this might be DALE ERC55?)
Line 2: 904H (Perhaps a date code plus "H" = ???)
Line 3: 3012 (30.1k Ohm)
Line 4: BSCJ (I am guessing B = 0.1%, S = Solderable and CJ is a reel/packaging code. It looks like a Dale part number but does not seem to exactly follow current Dale datasheets and is not marked DALE on the body.)
Can you confirm that these are "C" = 50 ppm, "B" = 0.1%?
What is the vendor and series? I assume DALE but not RN55. Perhaps ERC55?
The second type are Light Brown and are marked:
Line 1: DALE
Line 2: 9651J (Date code plus JAN/Joint Army - Navy)
Line 3: RN55C (RN55, "C" = 50 ppm)
Line 4: 3012B (30.1k Ohm, B=0.1%)
So these look like RN55, "C" = 50 ppm, "B" = 0.1% unless I am wrong.
The third type are LIGHT Blue and are marked:
Line 1: P (Does this signify a different brand/vendor?)
Line 2: RN55C (RN55, "C" = 50 ppm)
Line 3: 3012B (30.1k Ohm)
Line 4: B (B=0.1%)
So these look like RN55, "C" = 50 ppm, "B" = 0.1% unless I am wrong.
What does the P signify (different brand)? Why light blue instead of light brown like the second type? (Brand?)
I also would like to figure out the bag of light blue 20k resistors which have four bands for 20k value (Red Black Black Red) and then gap with a "2" printed on the light blue lacquer and then a violet band. Anyone recognize what these might be especially with the little "2" printed between the four value color code bands and then the fifth violet band? I have never seen a little "2" printed on a resistor before like this. At first I thought it was a brand symbol but under the microscope it is a little 2. The fifth band is violet = 0.1%.
So it looks like 1/4W 20.0k 0.1% but what does the "2" mean?
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After more searches I have found that the light blue RN55C marked "P" are likely from Philips Components.
I also found that "S" might mean S (0.001%) Fail Rate.
Can anyone confirm if BSCJ printed on a DALE RN55C means B=0.1% Tolerance and S=0.001% Fail Rate?
I also found that "S" might mean S (0.001%) Fail Rate.
Can anyone confirm if BSCJ printed on a DALE RN55C means B=0.1% Tolerance and S=0.001% Fail Rate?
There were various Mil Specs for metal film resistors. Some were superceded by different ones. It can be a puzzle to find the spec that matches the format of the markings. So some have a J (for JAN or Joint-Army-Navy) after the date code, like some you have described.
Another marking system placed the J as the last character, like your example of BSCJ.
The B after a number like 3012B or at the beginning of BSCJ does indicate 0=+/-0.1% tolerance.
You are correct that the S is a failure rate (you have to read documentation to find out what constitutes the range of parameter changes that constitute 'failure'- it doesn't mean they just go bad on a whim or spontaneously combust).
I don't remember what the C indicates before the terminal J. I will try to remember to look it up and report back (for anyone else who happens along).. I particularly don't remember because the C at the beginning has different meaning. I think I have seen RN55C and RNC55 over the years which mean different things...
and the 91637 doesn't have anything to do with the ERC series. It is a CAGE (Commercial And Government Entity) code that identifies a manufacturer or former manufacturer.
91637 today identifies Vishay Dale Electronics, LLC. (source: https://cage.dla.mil/)
On older parts, you may find different CAGE codes that were for a manufacturer that may have merged with someone like Dale, or later Vishay. If you have packaging with one name, a CAGE lookup may give the merger/acquisition name at a later date. So the difference is probably not wrong, but due to different time frames (old parts).
Their datasheets are very comprehensive. If you cannot sleep and want to read a lot more, and know a specification name, you can find many of them on everyspec.com
Another marking system placed the J as the last character, like your example of BSCJ.
The B after a number like 3012B or at the beginning of BSCJ does indicate 0=+/-0.1% tolerance.
You are correct that the S is a failure rate (you have to read documentation to find out what constitutes the range of parameter changes that constitute 'failure'- it doesn't mean they just go bad on a whim or spontaneously combust).
I don't remember what the C indicates before the terminal J. I will try to remember to look it up and report back (for anyone else who happens along).. I particularly don't remember because the C at the beginning has different meaning. I think I have seen RN55C and RNC55 over the years which mean different things...
and the 91637 doesn't have anything to do with the ERC series. It is a CAGE (Commercial And Government Entity) code that identifies a manufacturer or former manufacturer.
91637 today identifies Vishay Dale Electronics, LLC. (source: https://cage.dla.mil/)
On older parts, you may find different CAGE codes that were for a manufacturer that may have merged with someone like Dale, or later Vishay. If you have packaging with one name, a CAGE lookup may give the merger/acquisition name at a later date. So the difference is probably not wrong, but due to different time frames (old parts).
Their datasheets are very comprehensive. If you cannot sleep and want to read a lot more, and know a specification name, you can find many of them on everyspec.com
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RN55C +/- 50 ppm / degree C
RN55D +/- 100 ppm / degree C
RN55E +/- 25 ppm / degree C
RN55D +/- 100 ppm / degree C
RN55E +/- 25 ppm / degree C
