Underwriters Laboratories (UL) Fuse Question

Man Lyn, seems you've pissed somebody off again to be voted OT! Anyhow, I tried to over-ride the OT. Nice find and as the Britt's would say, "Spot On" the subject!

Have a good one

Dan

Thanks.

As I say in my signature line, "The supply of fools will always outstrip the demand."

Indeed, currently at 1 to the plus. So, let's knock it all the way. GA

Thanks.

Interestingly enough, I cannot see what the vote count is for my own threads.

No one can see this for their own threads. We can see it for everyone else's though.

Don't know who the fool is but it isn't me. You got my GA!

Good Luck, Old Salt

Honest, guv, I did google first! Now I just need to find an in-line fuse holder that UL likes...I would ask the UL guy, but it seems they charge by the word for any questions :-/

Drew K

No, but the relevant details are whether or not the manufacturer saw fit to get UL certification (which as you've discovered, simply certifies the samples tested meet the pertinent standards and really has nothing to do with actual quality or practicality), and this decision was likely made in view of the target market. So if the target market for the blade fuses is automotive and they may only require SAE certification, why bother with UL?

Just as a further note, here in Canada UL doesn't mean much, we would normally require CSA certification instead or cUL (don't know what the testing difference is from UL!).

"Just as a further note, here in Canada UL doesn't mean much, we would normally require CSA certification instead or cUL (don't know what the testing difference is from UL!)."

As a rough guess, I would say that CSA certification means it was tested by/on actual Canadians, while UL certification means you're simply taking the word of a bunch of 'Yanks' on it.

(I KNOW the Canadians have a derogatory word for Americans, which they would mutter behind the backs of the more moronic examples of our countrymen, but you guys are SO darned polite you never say it where it could be overheard. It's hard to do self-effacing humor if I don't know what insulting term to use on myself.)

You're likely quite right! Sorry, meant to say the difference between cUL & UL.

PS- I think most of us Canadians just call you da.ned Yanks, but that just shows how original we aren't. We had to pick up something from south of the Mason- Dixon line to use instead, and probably as many Canadians know that bit as Americans know that the US didn't win the war of 1812.

PPS- my wife's grandfather is a very proper Bostonian, so you can guess what amusement we can get out of it all!!

I thought the Canadians got Yank from the Brits who have been using it as a derogatory term for an American with too much head on his shoulders propped up by a large chip.

Most of the Canadians I have met seemed more European than American.

Drew K

Septics is a description used in the UK.

Um...I know. Used as in an even more derogatory context than just calling someone a yank.

Drew K

"Americans know that the US didn't win the war of 1812."

We weren't *IN* the war of 1812, that was when Napoleon tried to invade Russia and got his had handed to him in SHORT order. They even made a big song to commemorate the victory; it gets played at the end of our Independence Day celebration in DC.

Yes, we celebrate the birth of 'The Most Democratic of Democratic Nations' by playing a song that honors the victory of Imperialist Russia over the Democratic French. But who cares, it's a piece that has actual cannons written into the score. CANNONS! You know we yanks love to fire off guns, and the bigger/louder, the better.

(Yes I know there was a 'war of 1812' on American soil, but everyone remembers the '1812 Overture' and forget that you can have wars on two different continents in the same year. So this is mostly me putting on the hat with bells on it and dancing around to amuse. Although the irony of praising the Czar in song (which we do, the section used for A Capitol Fourth includes the Choir singing) as part of celebrating our own democracy is quite real, as well as the realization that most of the people out there on the lawn cheering on completely miss the point because they don't know what the 1812 Overture is about.)

(( and to be topical (which means this will be 'old and dated' next week) Happy Thanksgiving up there ))

It would help if we knew some more details like the Voltage and Current ratings, any particular time vs current requirements, are they there to protect the wiring and/or the device, etc.

We are seeing max amps of only about 2 amps on start-up and less than an amp when running. We have used 1.5 amp slow blow glass fuses without problems. The circuit board has current limiters (so says the EE guru we contract) that make it difficult to blow the delay fuses.

I want to use the blade fuses to reduce cost but my boss says we have to pay UL to review it to lower the cost...so if the reduction isn't enough we just keep making the customer pay until we feel like paying UL?

Drew K

What sort of voltages are these fuses interrupting?

Those clam shells are normally on tail conductors...

Sorry if I forgot to mention, 12V DC.

Drew K

The "clam shell" type fuseholder only contacts the fuses on the ends of the fuse. This can cause the fuse to overheat and fail, not necessarily by an over load. Motorola used to have a fuse holder that had contacts that fit over the ends of the fuses. Contact your local two way radio shop, they may be able to assist. IIRC they came with a single piece of wire that was cut and spliced to the particular circuit.

Littlefuse make a UL248 compliant arc quenching blade fuse that may be acceptable.

According to my catalogue the one that likely best fits your requirements is a 3 amp unit part number 166.7000.430. Or a 4 amp one 166.7000.440.

Google the number and you should be able to access a datasheet.

What voltages/currents are you wanting to fuse?