Okay, so I’m ashamed to admit I had never put a seconds thought into the quality of fuses, but now I’ll never replace one without thinking of it. Thanks! Great topic and explanation.
@WeberAuto6 жыл бұрын
Awesome! Thank you!
@kayceedee3 жыл бұрын
I'm as equally ashamed to admit, I asked the auto store personnel if all auto fuses are "pretty standard". He said yes. LOL! I bought the Bussmann E-pack.
@floyd278602 жыл бұрын
I found this on a whim. I never thought there would be a difference in manufacturer of fuses. Shout out to you!
@ZookeeperJohnG4 жыл бұрын
You Sir, are a Rock Star and Weber should be proud of you and your work. Please also thank them for allowing these informative videos to be taped at their facility and published!
@robertoruiz70695 жыл бұрын
Thanks john ,as a auto tech student 40 years ago in college,I'm glad to see that this type of teaching is not totally gone.Your students are very lucky to have you as a teacher.I just learned that my thought processe on buying MORE FOR LESS ---was--- IS wrong !!! In most cases it pays off to buy the best,a FUSE should be thought as a safety feature like good brakes and good tires.thanks again john.HEY IS that why there sometimes called safety fuses?
@kahvac4 жыл бұрын
Thanks John for the education. As a Master Electrician doing mostly Industrial troubleshooting I never knew the importance of quality fuses, I thought a fuse was a fuse. The implications of using inferior fuses should be criminal. Thank you for the heads up ...I was never taught this at school that's why I come to you !
@kahvac2 жыл бұрын
@Gormen Freeman Possibly...but willing to bet a lot of the shops just don't know there is a difference.
@glenngoodale17096 жыл бұрын
You are undoubtedly the biggest one man operation that I have ever come across in my long life. Its great to see a young man making the most out of life, working hard for what you want and doing it like an old pro.
@WeberAuto6 жыл бұрын
Thank you!
@mh2378g Жыл бұрын
Thanks for this. I am a retired auto mechanic- I suspect this information is often overlooked, and is so important! Thanks for covering this in such detail, so people can make an informed decision. Great Job!
@SuperMarioDiagnostics6 жыл бұрын
Nice were seeing it in action! Thank you for sharing professor! I'll be catching up on this soon
@WeberAuto6 жыл бұрын
Thank you!
@stephenwgreen786 жыл бұрын
Those eBay fuses are great. They'll last forever:). You're wiring harness may not, but you'll never buy fuses again lol. Thanks for a very informative video.
@WeberAuto6 жыл бұрын
LOL! Thank you!
@compu856 жыл бұрын
Sounds like FPE home circuit breakers that never trip!
@citylockapolytechnikeyllcc79363 жыл бұрын
I ordered Bussman Caddy1 kit for the shop from Zoro. Should be here today, to replace the kits I have bought of anonymous quality. They matched lowest online price of 126.00 for a 275 piece set of 4 boxes in a caddy. BTW, your channel is very illuminating. I grabbed a tester and one of these old kits, they all measured about 1.2.... all "colors" I cant call em Amp anymore. Thank god the auto makers use thinner wires.... so they melt if the fuse fails, thus the wiring IS the fuse !
@DiagNetwork6 жыл бұрын
Thanks for sharing John, the automotive service communities appreciate the intel!
@WeberAuto6 жыл бұрын
Thank you!
@lcastelano6 жыл бұрын
I am astonished . I never thought a fuse can be so complicated . Thank you sir.
@WeberAuto6 жыл бұрын
Thank you
@SouthMainAuto6 жыл бұрын
Fantastic job sir!
@WeberAuto6 жыл бұрын
Thank you!
@Nudnik16 жыл бұрын
South Main Auto Repair hey I watch your cool show!
@rondhole4 жыл бұрын
Thank you very much Prof. Kelly, this is very crucial for all cars owner. I will never buy fuses or electric safety devices over unknown brands. Just check generic fuse on Total, Shell, Agip, and Aral gas station in Germany. All those fuses are from Bussman
@FreedomToRoam863 жыл бұрын
Good to know those Bussman and Little fuses are the right ones to use!
@WeberAuto3 жыл бұрын
Yes! Thanks for watching
@___Karma__3 жыл бұрын
This was a very thoughtful demonstration with thorough explanation. Thank you for the knowledge 😁
@haywardsautomotive61566 жыл бұрын
Great video Professor!! One of the best videos on fuses and the mA tester is just scratching the surface on it's uses. The damage from a fuse not blowing will not be worth the few dollars you saved. I've used Bussman my entire career and won't be changing anytime soon!
@WeberAuto6 жыл бұрын
Thank you very much! I totally agree
@volvo096 жыл бұрын
Excellent! I figured the low quality fuses were junk just by what I've seen come out of China for low quality parts, but I just assumed they were junk due to tolerance variance, not the fact that they are SO FAR OFF that it's overspec by 5x!! I need to buy a collection of fuses and this solidified my decision on name brands!
@WeberAuto6 жыл бұрын
Thank you! It is incredible how bad they are
@mchabbi4 жыл бұрын
These videos are really great. Thanks for doing this. By the way, that is Litt-E-Lfuse, it is usually misspelled as Litt-L-E-fuse most places.
@davidkendrick2133 жыл бұрын
I’m a retired project manager for the F16 (F110) GE engine). I am aware of the difference in fuses. However, the normal auto owner does not understand the differences and will go for the cheaper fuse not understanding they could be damaging their cars electrical system. Thank you for pointing this out.
@josephbonner8424 жыл бұрын
Thank you for your time proving the difference. I now know what to purchase. Thanks again.
@WeberAuto4 жыл бұрын
Thank you
@chekelley68616 жыл бұрын
Who knew a lowly fuse could be so interesting!
@WeberAuto6 жыл бұрын
Thank you! I agree
@bimmermavenwrench16606 жыл бұрын
sorta like seat belts, fire suits, crash helmets, roll bars, air bags, sunscreen, safety glasses, welding gear, guard rails, surge suppressors, cholesterol pills (I'm getting old).....no one wants to pay for protection...until they're not protected! Mentally, we're much happier fixing something that's broken than preventing it from breaking in the first place.
@robc.57454 жыл бұрын
Very thorough and complete ,Sounds very technical but the bottom line was don't buy JUNK.I just had a problem yesterday with a fuse and was riding the fence on which one to buy, I made my choice now Thank You.
@195531296 жыл бұрын
Love your videos. I learn something every time. Thank you.
@WeberAuto6 жыл бұрын
Thank you
@nv14934 жыл бұрын
Really helpful. Several years ago I had a cheap chinese fuse weld itself into the contacts , fried a section of harness. Since then I'll gladly pay the difference for Buss or Littlefuse.
@vincescalise48214 жыл бұрын
I just bought a bunch of those fuses from eBay, guess what they’re going to go in the garbage thank you for the information, it’s like they always say if something sounds too good to be true, it probably is ,Thank you for all your great videos professor
@windward28182 жыл бұрын
Bussmann and Littlefuse have automotive blade and cartridge fuse product lines that overlap in most instances, with some fuse designs unique to the manufacturers. The most popular domestic fuse types are blade types: Maxi, ATC/ATO, Mini, Low profile Mini, Micro2, Micro3 and cartridge types: JCASE, Low profile JCASE, MCASE and Slotted MCASE. Beyond the types mentioned there are also large amperage bolted fuse types. In their entirety, the motivation for the different types is space (size), closed or open element (environmental and opening thermals), opening time-current (basically; fast or slow blow), and isolation (shrouded and separated connection points). Cost is also a factor, but is many times not as important as space (which also translates into cost), for example with cartridge fuses (nominally small form factor high current slow blow with better isolation rating).
@gonefilming2020 Жыл бұрын
Thank you, Professor, for taking the time to do this video. I am a licensed technician having over 40 years experience within automotive dealerships. We only used OEM fuses from our parts departments and they came from the manufacturer. So I never questioned the quality. With online platforms selling chinese knock-offs so far out of spec, sensitive and expensive car components are at risk. Your video is an eye opener and actually required info for van builders putting in their very own electrics with online purchased components. Question: I have a 10MOhm sensitive meter with a listed inaccuracy of 8%. Can I qualify my bin of fuses using the specs of Littelfuse or Bussman?
@TRYtoHELPyou6 жыл бұрын
this was a great thing to watch. thanks man! you are great!
@WeberAuto6 жыл бұрын
Thank you!
@Dwigt_Rortugal Жыл бұрын
I specifically searched for this info and your video came up. Holy crap, those are so far out of spec, it's criminally negligent. Thanks for making this. I had no idea that shunts came in all those pretty colors!
@glenmartin2437 Жыл бұрын
Thanks. I passed the info onto others. This is the best video on bad fuses.
@Henry-ij1nt3 жыл бұрын
Fantastic video! I've been having electrical problems on my car for years and multiple mechanics can't tell me why the errors are intermitten. After watching this, I think I'm going to check through all my fuses to see if somewhere along the line a crap one was put in. Especially since the electronics are so sensitive in the cars these days.
@fahmial-wadhahi70792 жыл бұрын
Thank you very much professor, I was about to purchase the cheap fuses & you have saved my life 😘
@zackarymcclain164 Жыл бұрын
I never considered the resistance value of the fuse element when considering the quality of the fuse. I have seen tsb's from gm regarding the cheap fuses from import tool stores. It makes sense that with higher resistance you have lower current flow and with lower resistance you have higher current flow. I guess I'll have to use 2amp harbor freight fuses for my 10 Amp circuits 😂. I am quite a curious person and I think I'm going to try blowing fuses using my current clamp and pico scope to see the amount of current required to blow these cheap fuses. Your videos are an amazing source of information and knowledge. As a student of all things automotive your videos are pure gold. Thanks for sharing!
@MB-ke9mi2 жыл бұрын
I've been doing car electronics on my projects for years and never gave a second thought about the quality of these fuses until I was on Amazon and wondered why 240 fuses could be bought for 10 bucks. I thought I should investigate a little further into the quality of these fuses and after watching this video I too am ashamed of the fact that I never really thought about it. Thank you for this video I will gladly spend a lot more money on better quality fuses.
@toyotatechMDT6 жыл бұрын
Nice video, very interesting. You get what you pay for has never been as true!! Thanks John.
@WeberAuto6 жыл бұрын
Thank you very much!
@waynegoebel3954 жыл бұрын
Great to know and thank you for the time taken to make this video.
@bobflannagan72622 жыл бұрын
Amazing, absolutely amazing! With true gratitude . . .
@fernandor8873 жыл бұрын
Love your videos and the importance of good quality products
@SumedhaManabaranaKandy Жыл бұрын
Profoundly beneficial. Subscribed and shared on Twitter. Thank you, Professor.💐
@cees19106 жыл бұрын
What a great video. You opend my eyes to fuses And probely helping saving lives
@WeberAuto6 жыл бұрын
Thank you very much!
@wynnyoder56052 жыл бұрын
I am a retired engineer from Littelfuse. Tin is NOT used for plating the leads. If you find tin, it will be minimal.
@juanvicentemedina91106 жыл бұрын
Nice explanations. No one think on that and people always looking for the cheapest fuses. Best way to get quality fuses and cheap are the salvage yards.
@WeberAuto6 жыл бұрын
Thank you!
@Ali_ON3 Жыл бұрын
Thank you for this video. I got sus after seeing 105 fuses for $16 CAD on Amazon compared to LittleFuse @ $18 for 14 fuses at Canadian Tire. Such a huge difference didn’t make any sense to me, i started searching and landed on this video and as suspected Amazon is selling garbage. Bought LittleFuse kit and now hardwiring my dashcams.
@kayceedee3 жыл бұрын
Thanks so much for the explanation and test studies, awesome!
@terence123cars3 жыл бұрын
This is an excellent vidio so detailed as to variing loads, However the fuses most important job is to open a short circuit load !
@WeberAuto3 жыл бұрын
You are correct. Thanks for watching
@sharg04 жыл бұрын
A couple of important notes: A fuse doesn't melt a wire - it fails to protect it when a fault (overload) occurs. And while resistance is usable to verify a known fuse it can't be used to judge an unknown since the material used determines both the resistance/A and the melting point. That said, fuses are important and definitely needs to be manufactured in a controlled way to specification. Would have been interesting to see a simple load/overload test for the smaller fuses to see if those results matched the theory (most likely). A 5 A fuse should handle a single 55 W bulb driven by a car battery (about 4.5 A) but trigger for two in parallel. This also highlights an issue with this style of fuses, they are all the same so nothing stops someone from replacing a blown fuse with a larger one!
@WeberAuto4 жыл бұрын
Great points, thank you
@joshm3342 Жыл бұрын
Many styles of fuse come in multiple ratings. Education is the best way of preventing stupidity.
@WouterB76 Жыл бұрын
Your channel learns me so much!
@waltham16545 ай бұрын
As a retired Electronic Technician you gave a through explanation and testing to convince people to buy quality parts. I tell people all the time to buy Dealer parts especially electronic parts. If the part fails after thousands of miles it's safe to say it will last another thousand miles.
@MyGoogleYoutube4 жыл бұрын
Wow, I picked the wrong place to save money. Thank you for doing this!
@michaelhains22917 күн бұрын
This video has set the global standard on lousy fuses. I learned so much.
@genuinetuffguy18542 жыл бұрын
Thanks for doing this! I was suspicious of the cheap fuses on Amazon and this confirmed my suspicion. It would have been interesting to see the same comparison for Bosch fuses.
@k24hybrid6 жыл бұрын
Excellent!! As always!!
@WeberAuto6 жыл бұрын
Thank you!
@ralfsautomotive Жыл бұрын
Nice Video! Oddly I would have thought this to be the other way round.
@snake105666 жыл бұрын
Fantastic video! Thanks for sharing!
@WeberAuto6 жыл бұрын
Thank you!
@Randomgearhead6 жыл бұрын
the cheapest place to get quality oem fuses is your local salvage yard. and the rule of thumb is if it fits in your pocket they are free, so even cheaper than ebay!
@WeberAuto6 жыл бұрын
That is a great idea!
@juanrodriguez-ry6yt6 жыл бұрын
been doing it for years
@stevenjames70736 жыл бұрын
Fantastic idea
@HoosierDaddy_6 жыл бұрын
I pull fuses and relays everytime I go!
@Kewrock6 жыл бұрын
Yeah but who knows what the previous owner or repair shop stuffed in there. You can't tell by looking at them, and you have now idea of the car's history.
@SvcGlobal5 жыл бұрын
In my experience I realized that some fuses the element (and contacts) are made in aluminum and others in copper and some in brass. The aluminum made ones are the worst and are completely out of specification. Thank you Professor, outstanding video as usual.
@woodsprout3 жыл бұрын
Thank you, saved me from buying crappy fuses !
@1corvair26 жыл бұрын
What great information, who knew...Thank you very much
@WeberAuto6 жыл бұрын
Thank you!
@Joetechlincolns6 жыл бұрын
Thank you for making this video.
@WeberAuto6 жыл бұрын
Thank you
@dirtyfingernailsauto89466 жыл бұрын
Eric O. , funny seeing you here , I thought you only hung out with Ivan and keith HAHA , Love your channel BTW . and this one Too !!!!
@airmailman19713 жыл бұрын
Another great job. You are a treasure sir.
@googacct6 жыл бұрын
Thanks for posting this. I for one probably would have bought one of those cheap bargain packs from ebay or amazon thinking a fuse is a fuse. I will not be doing that now. A couple of things that might be interesting to check with your new toy. Check contact resistances of oem and non-oem replacement switches. Also checking resistance of connections at battery terminals and alternators. Especially if you could compare clean terminals with corroded terminals.
@WeberAuto6 жыл бұрын
Thank you! Great ideas
@Mr549er4 жыл бұрын
great demo mr-John
@ianham2 жыл бұрын
Thanks for the great information. My 87 VW thanks you.
@perryreasch12094 жыл бұрын
Fantastic so good never new this
@WeberAuto4 жыл бұрын
Thank you
@xerxes4566 жыл бұрын
I think it was south main auto channel when he had a meter on a circuit to test it, a meter was showing 20 amp with a circuit fused with 10 amp fuse, I think people don't trust the resistance value but what's make amp is voltage and resistance and resistance makes heat, great test don't trust cheap items but did not think of this, great video thanks for uploading it for education and it makes things safer and in the end could save lives.
@WeberAuto6 жыл бұрын
Thank you very much!
@adventurehypelife38192 жыл бұрын
Thank you Sir for this great information.
@TheGibby33404 жыл бұрын
Very interesting indeed. Thank you Sir. 👍
@JeffinTD Жыл бұрын
I figured bargain fuses wouldn’t be quite as precise, but was shocked when another channel demonstrated a 5 amp fuse not blowing at 20 amps. Bussman or Littelfuse for me from now on.
@MaximC3 жыл бұрын
Had no idea about this, and bought some cheap fuses from Aliexpress. In this case I shall use the cheap ones only for unimportant things, and good quality ones - for everything else. Thank you.
@daveco1270 Жыл бұрын
This was very helpful, thank you. I was wondering if the fuses they sell at my local AutoZone are the same ones you'd get on Amazon for cheap. I currently have a box of the amazon fuses I've been using. Not sure the grand but they've always felt a little cheap... the metal prongs feel too thin. I'm going to replace them with a better brand ASAP.
@tk421tt5 жыл бұрын
exactly what i was looking for!!!
@rudyossanchez6 жыл бұрын
Hello professor, thank you for the videos
@WeberAuto6 жыл бұрын
Thank you!
@MasJets6 жыл бұрын
Great information, thank you
@WeberAuto6 жыл бұрын
Thank you!
@artyzinn77252 жыл бұрын
I was very skeptical when I saw brand X atm atc fuses on ebay amazon etc., and H. freight from 2016, as quality fuses have detailed datasheets, the no names have nothing to show for it. I did failure tests on 3 and 5 A littlefuse atm and a set from H. freight by increasing Adc 0.5A in 1 sec increment on 2 samples each. The Littlefuses blew within the specified data curves for the 1sec failure point, 4.5A for 3A , and 6.5A for 5A while the H.Freight 5A blew at 9A .. for both samples. If your devices specifies fuses similar to Littlefuse, the H. Freight are incorrectly rated, but at least the 2 samples being nearly identical suggest the quality control has improved. Also littlefuse atm fuses are sealed, while the HF fuses are open, so fuse elements are exposed to the environment. Given how rarely fuses blow it pays to get a quality fuse. Thanks for the detailed testing and more power to you.
@nhra71106 жыл бұрын
great video! Thank you.
@WeberAuto6 жыл бұрын
Thank you
@charlschuck64 жыл бұрын
They are not created equal 😉 in other words thanks wow never even though this could happen under the hood , that’s why many ask well this are cheaper why buy an “over priced fuse” when in reality your buying protection to your car/ electronics . Thank God for the knowledge he gave you not much ppl even think of taking the time to do such an experience and explanation even at school of tech .
@leisurehobby99805 жыл бұрын
Thank you so much Professor.
@mrmudstud59803 жыл бұрын
Excellent Job.......
@WeberAuto3 жыл бұрын
Thank you!
@Diagnosedan6 жыл бұрын
Are you going to check at what current the fuses pop? I'm curious😁
@WeberAuto6 жыл бұрын
Not anytime soon. It is a current verses time test. I don’t have the equipment to do that. Anyone can short circuit one.
@annierenard59546 жыл бұрын
very informative thank you
@WeberAuto6 жыл бұрын
Thank you
@johnmott80474 жыл бұрын
Harbor Freight never fails to incite a chuckle
@asabovesobelowas7 ай бұрын
Question. Excluding size. What's the difference between a Standard and mini with the same amperage?
@edson507512 жыл бұрын
So I bought some fuses at autozone. I believe it was the bose fuses. The blue 15 fuse kept blowing for my rear lights. I tried all the fuses in the kit and It kept blowing and I switched the bulbs and still nothing. I had to stop at autozone the other day because I needed the lights on to get home. Well I bought some fuses that a little red light turns on when the fuse blows but it didn’t blow! Those fuses are more expensive. I had no choice but to buy those but it fixed my problem!
@fahimmahmad9731 Жыл бұрын
Thank you so much for you're wealth of knowledge I'm so glad I've seen this one about fuses I was about to buy from Amazon a box of different fuses of all the amps I've enjoyed your video's I've subscribed to all your video's so thank you I've learnt a lot watching your video's you're so easy to listen too I'll get my fuses from my local store Car accessories not amazon or Ebay I don't know if it's possible to get the fuses you have LittleFuse or Bussman type as I'm in London uk I'll check anyway if not possible I'll go to my local garage so thanks again for a fantastic video I've enjoyed you're videos Greetings from London UK ....
@erolevrim69343 жыл бұрын
Very helpful, thank you
@foobar31393 жыл бұрын
Wanted to know a legit brand name for fuses, thank you!
@rmancuso49042 жыл бұрын
Without knowing what metal is being used (as well as their thickness etc.) in the generic fuses and at what temperatures they melt and open the circuit this video leaves open the question at what amperage and after how much time would the generic fuse blow. Simply comparing resistance does not answer that. Just because the 10 Amp generic has same resistance of a 35 Amp name brand doesn't mean it will necessarily behave like a name brand 35 amp fuse. The fact that the generic allowed the wire to get hotter does indicate that it might be a good proxy. Given that fuses usually blow rarely it seems paying a bit more for a name brand is no big deal.
@Dylant386 жыл бұрын
ive had many people tell me that a fuse is the same no matter who makes it, Being that im an automotive Technition with 2-5 years of working experience i have learned that cheap fuse''s are almost the same as making a jumper wire and just using it as a fuse, being that both wont blow at the amps they should, i chased a wire short from one side of a ford explorer passenger seat, to the rear of the vehicle and back to the fuse panel, it called for a 10 amp fuse, they kept installing larger ones until it had melted an entire wiring harness, they had cheap fuses and the last on they tried was a 50 amp Maxi fuse, lests just say it was more than i figured it would be on replacing the wires, all due to a shorted out Seat control switch. i wished people would leave stuff alone, this could have caused a vehicle fire. it doenst take long to diagnose a problem especially when it only called for a 10 amp fuse. may have been a 15 but still
@WeberAuto6 жыл бұрын
Thank you for your feedback. It is amazing to see the difference
@jonkessler62702 жыл бұрын
"i chased a wire short from one side of a ford explorer passenger seat, to the rear of the vehicle and back to the fuse panel, it called for a 10 amp fuse, they kept installing larger ones until it had melted an entire wiring harness, they had cheap fuses and the last on they tried was a 50 amp Maxi fuse, lests just say it was more than i figured it would be on replacing the wires, all due to a shorted out Seat control switch." It sounds like the cheap fuses worked as they should, by blowing. But instead of diagnosing the reason that the fuses kept blowing, the customer installed higher amp fuses until the wire harness melted. Oddly enough, I've seen a review by a customer about how a given fuse kept blowing. That's actually a compliment. If a fuse is blowing, then it's doing its job. Maybe something else is giving the fuse problems.
@stevenjames70736 жыл бұрын
Thank u for sharing ,may the lord bless u
@WeberAuto6 жыл бұрын
Thank you!
@stephenwgreen786 жыл бұрын
Also, if you find time to recreate this for the eBay resetting fuses (they're for testing different components on a circuit to figure which one is shot
@forza8904 жыл бұрын
Thank you!
@WeberAuto4 жыл бұрын
You're welcome!
@arnarmar756 жыл бұрын
After quick google search I see there are of course specifications for this as everything else in this world 😀 Seems most as referring to ISO 8820 or SAE J1284. Section 6 in part 2 of iso 8820 covers cold resistance. Would be interesting to read these specs, but the iso is plit in 11-parts and each one costs $60-$90....I want to spend my money in something more useful. I'm sure the ebay crap doesn't comply to these standards, but it would be really interesting to see how they blow compared to some branded ones.
@WeberAuto6 жыл бұрын
Thanks, I showed the SAE J1284 in the video.
@namdarbolour98902 жыл бұрын
Not knowing anything about the exact metal used in fuses, I imagine different makes could be using different metals for the part that melts. If so, they may have different resistance and melting points. So you can't use resistance measurements as a measure of quality. Is this a possibility, or are all fuses made with the same kind of metal (copper). The standards doc you cited has specs in ohms, so that would mean all fuses are made from the same metal?
@monky1233442 жыл бұрын
Different fuses are made with a very small selection of different metals. I'm not entirely sure what most companies use for small automotive fuses, but almost all industrial fuses are copper or silver. In general resistance won't be the best indicator of quality because different element geometries can lead to different opening times, but it is a pretty good sanity check for the rating of the fuse--the off brand ones were clearly way oversized for their rating.
@SkaBob Жыл бұрын
I would have like to see at what current the different brand of fuses actually blow at.
@V10PDTDI6 жыл бұрын
Thanks professor. I was thinking let’s say that someone was chasing a parasitic amp draw on a car and measuring the voltage drop on the top of the fuse I know there is a chart that tell you what amp is being drawn from a specific fuse amp rating let’s say it’s a 10 amp fuse there is a scale for that specific fuse it will tell you if the circuit have a current draw and how much but if the fuse it self doesn’t meet the specs then this test will not be valid so it’s important to check to see if the fuses are of good quality I wonder if the brand name is shown on the fuse to help identify good ones from cheep ones ?
@WeberAuto6 жыл бұрын
That is absolutely correct, the voltage drop across the fuse is affected by the resistance of the fuse. the cheap fuses have the wrong resistance, so the voltage drop will probably not be in the correct range for those charts. Thanks for your feedback!
@ablackformula6 жыл бұрын
True, but a circuit with no parasitic draw should have 0 amps and a 0v drop across the fuse. You're looking for a fuse with any voltage drop greater than 0v.. Depending on how close the fuse is to its spec will determine how accurate your voltage drop correlates to the circuits current flow, but by that point at least you've identified the circuit with the draw. If you want the real current flow you can pull the fuse, install a fused loop of wire with a clamp-on ammeter, and continue. Of course you'd have to wait for any modules to reboot and go back to sleep, but you'd be on a much more direct path at that point! Now you can also turn things on and off, wiggle harnesses, etc and monitor the current flow for changes without having to hold the test leads to the tiny fuse connections.
@WeberAuto6 жыл бұрын
Good point, thank you!
@stinkycheese8046 жыл бұрын
That's not really the right way to do it. Parasitic draws slight enough that the fault isn't obvious, are usually only tens to hundreds of mA. That across a few mOhm fuse is not much drop. You are better off measuring current with the meter in series at the battery and then selectively pulling out one fuse (or relay) at a time while observing the current change. Plus that tends to not only be more accurate and easy, it also takes less time than looking up the manufacturer of a fuse, then looking up the datasheet, then calculating out the voltage drop vs current. It would all be a waste when there is the better alternative of measuring at the battery.
@andufuse6403 жыл бұрын
good lesson
@WeberAuto3 жыл бұрын
Thank you
@patsplat5 жыл бұрын
Great test!
@carlosw16872 жыл бұрын
Doing a visual inspection a of generic Chinese fuses, the internal metal strip that is supposed to melt they all look the same thickness regardless of the amperage rating. I expect the 2 amps metal strip should be way thinner than the 30 amp one. But just by looking at them, they both look the same thickness. Is that a problem? Thanks