Can Anyone Explain This Symbol.........

[The Mighty Volt]

Hi there, I have been finding this on the A123 cells, especially the 18650 variant off Ebay, and then I found it again on an old, relatively insignificant motor which I came across in a pile of scrap.

Thanks...

 

[The Mighty Volt]

Ahhhhh................http://www.eiminc.com/UL/index.htm

Learn a new thing every day I guess.

 

[mwkeefer]

The RU, with the backwards "R," is what UL calls a Component Recognition Mark.
It is used only on components (think sub components, capacitors, termination blocks, outlet plugs with ground, etc) that later will be included in a complete product that will subsequently be tested by UL. Such recognition limits the use to specific conditions and / or situations only. Plastics are Recognized Components, as certain uses would be safe and some not safe. The UL Component Recognition Mark, RU, limits the use of such components to what has been deemed safe (ie: below 90C external temp, etc).

Transformers also could fall into that category. I recently spoke with a manufacturer who tried to tell me that the Component Recognition Mark on his transformer meant the whole product was "UL approved."

If anyone tells you their product is "UL Approved" - you should seriously investigate further, since there is no such thing... devices which bear the UL mark (not the RU or UL with classified stamped through it) are not "Approved" but rather "Listed"... for a device to be listed, requires successful testing at UL labs.

So RU only indicates that part (a part) of the whole is not dangerous (fires, shorts, etc), UL isn't an approval simply verification that the "item" should not be dangerous in the sense of fire or hazzardous byproduct and UL with classified over it means the item is listed but for specific and limited uses.

Hope that helps, if your wondering... yes I plainly plajorized that from about 10 google results and kinda boiled it down for all

-Mike

 

[The Mighty Volt]

The RU, with the backwards "R," is what UL calls a Component Recognition Mark.
It is used only on components (think sub components, capacitors, termination blocks, outlet plugs with ground, etc) that later will be included in a complete product that will subsequently be tested by UL. Such recognition limits the use to specific conditions and / or situations only. Plastics are Recognized Components, as certain uses would be safe and some not safe. The UL Component Recognition Mark, RU, limits the use of such components to what has been deemed safe (ie: below 90C external temp, etc).

Transformers also could fall into that category. I recently spoke with a manufacturer who tried to tell me that the Component Recognition Mark on his transformer meant the whole product was "UL approved."

If anyone tells you their product is "UL Approved" - you should seriously investigate further, since there is no such thing... devices which bear the UL mark (not the RU or UL with classified stamped through it) are not "Approved" but rather "Listed"... for a device to be listed, requires successful testing at UL labs.

So RU only indicates that part (a part) of the whole is not dangerous (fires, shorts, etc), UL isn't an approval simply verification that the "item" should not be dangerous in the sense of fire or hazzardous byproduct and UL with classified over it means the item is listed but for specific and limited uses.

Hope that helps, if your wondering... yes I plainly plajorized that from about 10 google results and kinda boiled it down for all

-Mike

Cheers man. I thought, for a few hours at least, that the symbol was specific to A123....and that this motor was some piece of absolute brilliance.

Turns out it is just a specification of sorts, for the purposes of classification.

Cheers!!!

 

[mwkeefer]

Yep - it just means those parts (the A123s and the motor) are listed as components to be used in some other device which would then still need final UL testing and listing before you could label it with the UL.

Even if every part you used was RU, you would still need to have the final assembly (what will be sold to the public) tested and listed.

UL is only useful in that it tells you "This shouldn't start a fire in your house", other than that... UL listing is no sign of quality or performance.

Again, hope this helps!
-Mike

 

[The Mighty Volt]

Yep - it just means those parts (the A123s and the motor) are listed as components to be used in some other device which would then still need final UL testing and listing before you could label it with the UL.

Even if every part you used was RU, you would still need to have the final assembly (what will be sold to the public) tested and listed.

UL is only useful in that it tells you "This shouldn't start a fire in your house", other than that... UL listing is no sign of quality or performance.

Again, hope this helps!
-Mike

Thanks Mike.

Would I be right in saying, however, that a LiPo battery might not have such a marking? As distinct from a LiFePo4....or is that too fine of a distinction?

 

[mwkeefer]

Too vague or general...

I've seen LiFePo4 cells without RU, UL or anything else... and I've actually seen LiPo (not our type of high C rate stuff) with RU markings similar to the A123s you pictured and then enclosed or contained within a casing with a UL listing (laptop batteries if I am not mistaken)... also the LiPo cells in the iPhones have the RU markings but not the UL stamp to indicate the component cell is compliant with requirements/standards to be included in part of the final product (iPhone/iPod) which then must submit for testing to receive the final UL listing.

-Mike