Fluke fake multimeter fuse WARNING!

[cowboy]

I wanted to call attention to something that many of you already realize, but many other folks are unaware of.

This concerns the Bussmann, Littelfuse and other OEM fuses for Fluke meters.

I will use an an example of the two most common fuses for Fluke meters, the ones used on the Fluke 83, 85, 87 series and many other models.

These fast-acting Bussmann fuses (11A and 0.44A) are about US$34 each at retail, however Fluke has a special pricing on these fuses for Fluke owners of $9.30 and $7.00 respectively through Fluke distributors such as Digikey, Mouser, etc. - This is what the Fluke corporation pays for these fuses direct from Cooper Industries- Bussman, in lots of many 1000's of fuses, they don't mark them up over their wholesale cost in order to encourage people to use the correct fuses for their precious Fluke meter.

When you see these fuses on ebay or other websites for $3.50 or $5 or something like that, these are Chinese COUNTERFEIT Bussmann fuses and could easily endanger your expensive meter at best, or even start a fire and endanger your life at worse.  The real genuine ones are not even made in China, they are made in Mexico (and the fakes are also marked Mexico) You think you are going to buy them in lots of one or two cheaper than Fluke buys a tractor trailer truck load for? wake up!  It doesn't matter what country the seller is in, or what the fuse looks like, it's fake!


Example auctions:

http://www.ebay.com/itm/Bussmann-DMM-B-11A-1000V-DMM-11A-Multimeter-Fuse-for-Fluke-87-V-88-V-287-289-179-/261536107575
http://www.ebay.com/itm/Fluke-11A-1000V-DMM-11-A-Digital-Multimeter-Fuse-87-V-88-V-287-289-179-US-SELLER-/161104330017

regardless of what the price is, or what the photo looks like, buying fuses on ebay is a bad plan, just like with capacitors, 99%+ of the auctions are of very crafty done fakes.  Ebay is better suited to finding that great piece of vintage HP or Keithley or Fluke or Tektronix test equipment, NOT fake fuses and caps!


I am all about living frugal, but this is one place where you want to stick with authorized sources, and a great discount from Fluke, or you could pay dearly!

[P90]

I've always thought Fluke fuses are way overpriced, a rippoff actually. I'm almost afraid to measure current on my meters for fear of blowing a $10 fuse... lol

[RoGeorge]

Is there any proof they are fake, other then the price difference?

$34 for a fuse! 

[Vgkid]

I know fluke did offer a 5 pack of fuses for about $25.

[Whales]

For end users: having fake fuses is not the direct issue, it's whether or not they provide the same level of protection.

I don't have any Fluke's or Flukey fuses, but I did notice that cheap and brand name fuses seem to have different innards.  I think the sand is there to help quench the fuse faster, but I'm not sure.

Cowboy: could you crack open a fake and a real fuse and show us the differences?

[Jeroen3]

Maybe photonicinduction should test some.

[RoGeorge]

If one gets electrocuted for using fake fuse

AFAIK this kind of fuses are to protect the equipment and/or to protect against fire hazard at most. They can not save people from electrocution. It is hard to imagine how someone might die because of a Fluke with a cheaper 10A fuse, but there is no thing such 'idiot-proof' so it might be possible somehow.

Still, I totally agree with you to order the expensive ones for somebody else, and I will probably do the same. The psychological comfort may worth more then $30, especially if the $30 are not from my pocket. Marketing people certainly noticed that too, so I bet this is the main reason for a piece of wire in ceramic tube to be sold at the price of an average DMM. For personal use I will order the cheaper ones, because I see no real benefit from the expensive fuses.

[CJay]

That's not that simple. A proper HRC (high rupture capacity) fuse is designed so that in case of a high voltage high energy dead short, the fusing element will break at several points, rather than a single point, so internal arcing possibility is minimized. Quartz sand inside cools down the hot plasma so it also helps extinguishing the arc.
Finally, the casing of a high quality DMM fuse is epoxy soaked fiber glass on top of ceramic tube, not just a single layer of ceramic tube. In case of a short circuit, high pressure generated from quick evaporation of internal fusing element and heated air may explode the ceramic tube, but the pressure and shrapnel will be contained by the outer epoxy fiber glass layer. This prevents your DMM from exploding in your hand.

Bulletproof fuses essentially.

I've seen the shrapnel of ceramic fuses embedded in the inner case of an ancient television, it's amusing until you realise that could have happened with your eye, I would definitely prefer my multimeter to have the correct fuse even though I am highly unlikely to approach the energy ratings (there was an unfortunate incident with a 'scope tube EHT supply but that's rather embarassing and for another time)

[cowboy]

The point is - if Fluke will give you the very high quality $35 fuse for $7 or $9 depending on which one, why would you risk a $500 meter or a fire or whatever in order to save $4 on a fuse that rarely, if ever, will need to be replaced? - It's crazy.

[wraper]

The price is definitely feasible in China. I just did a search on a number of Chinese sellers, and it seems like $2.5 is a reasonable price. Some sellers even showed their formal invoice for these goods and some showed original package and import documents.

A lot of counterfeit things are sold in "original" packaging. Some eevblog members bought multimeter fuses from China and they were fake.

[wraper]

The price is definitely feasible in China. I just did a search on a number of Chinese sellers, and it seems like $2.5 is a reasonable price. Some sellers even showed their formal invoice for these goods and some showed original package and import documents.

A lot of counterfeit things are sold in "original" packaging. Some eevblog members bought multimeter fuses from China and they were fake.

It could be many sellers selling fake, but it is impossible to see all sellers sell fake.
All search results show ~$2.5 price range.

Why not, if all of you are looking is in the same price range.

[Zbig]

The point is - if Fluke will give you the very high quality $35 fuse for $7 or $9 depending on which one, why would you risk a $500 meter or a fire or whatever in order to save $4 on a fuse that rarely, if ever, will need to be replaced? - It's crazy.

Get real, it's not a "$35 fuse" and never was. That someone tries to charge you that much for it - well, that's a whole different story.

[oldway]

I think it's more an academic debate than anything. 

The danger with these fake fuses only exists when measuring on high energy circuits.

First, this is not the majority of users.

Next, industrial electricity and power electronics are disciplines where technicians/engineers must have the proper training.

This is my area, I know of what I am speaking about.

1) NEVER measure a current on high-energy circuit with a multimeter, always with a current clamp. 

2) we always check and recheck before making a measure ... the possibility of error or distraction is excluded.

3) an industrial electrician / power electronics engineer use his multimeter WITHOUT FUSE for safety 

To measure the voltage of a busbar 5000A 550Vcc is not done without extreme précautions because even the original fuse will probably not interrupt such a high DC voltage with high energy.

[Jeroen3]

1) Sometimes you're an idiot and measure Volts while the meter is connected in Amps. Flukes will beep at you. But you won't hear that in all use cases. ^{This will cause a plant-wide blackout when you're fixing the 10kV load sharing.}
2) When you're doing repeated work. This will be a point of mistakes.
3) He doesn't have a multimeter. He has an Voltage Tester. Such as an Fluke T90.

Sometimes you have to measure busbars, but you don't do this on the live busbars unless you can't possibly do it elsewhere. Often, busbars are near some kind of cabinet with control and/or measure electronics, and you can measure after the fuses or mcb.

[Neilm]

I've seen the shrapnel of ceramic fuses embedded in the inner case of an ancient television,

I did a test where we put very cheap multi-meter which had a glass fuse across a 440V supply (the meter was rated for 600V). I found part of the meter case on the other side of the room. We drew enough current to trip the 75A breaker.

[saturation]

You should buy your fuses from an authorized distributor because counterfeit is so abundant.  Not just Fluke DMM, but also automotive, and anything where safety is paramount; for cheaper fuses you can destructively sample test fuses to insure its to spec.

http://www.cooperindustries.com/content/dam/public/bussmann/Electrical/Resources/product-datasheets-a/Bus_Ele_DS_1047_DMM-B.pdf

For DMM fuses, you have quite a margin for error before they blow.  To save money get the Bussman brand, not Fluke [ they are made by Bussman anyway], they are about $7-10 each or less.

[joeqsmith]

This subject came up not too long ago.  I would not mind getting some known counterfeit HRC fuses from a few different sources.  The 440mA were about $5.00/ea from Digikey last time I bought them.  $10 for the higher current.   

I wonder what is worse, replacing a blown fuse with a counterfeit or jumping it out with some magnet wire.  At least with the wire, you're just being stupid.  With the counterfeit you may have just been scammed is all.   The end result may be the same.     

[BravoV]

For personal use I will order the cheaper ones, because I see no real benefit from the expensive fuses.

Yeah, right, better alternatives too for your reference ... 

[P90]

I recently purchased a Fluke 88 used for $25, and when I opened it up to fix the LCD ghosting issue, I found both fuses blown. Some genius had wrapped aluminum foil from a gum wrapper around the blown 15Amp fuse. I wish I took a picture to post...

[BMack]

Buy the fuses from Authorized dealers. $10 for a fuse isn't that bad unless you're blowing them all the time...and if you're blowing your DMM's fuse a lot your problem isn't with the fuse price, it's the thing holding onto the leads that's the problem.

[P90]

Buy the fuses from Authorized dealers. $10 for a fuse isn't that bad unless you're blowing them all the time...and if you're blowing your DMM's fuse a lot your problem isn't with the fuse price,     


it's the thing holding onto the leads that's the problem.

[george graves]

I wanted to thank the OP for the link.  I never measure high voltage/energy with my precious fluke. But I do have a brain fart once in a while and forget to switch the leads.

I'll have to order some of these! 

 

[joeqsmith]

I think I may have acquired some fake SIBA branded fuses.  I was thinking to make some sort of video comparing what I believe is a real one showing the following:

Non-destructive:
markings
length
weight
DC resistance
voltage drop at max current
case temperature at max current

Destructive
trip current
check filler

[Fungus]

I think I may have acquired some fake SIBA branded fuses.  I was thinking to make some sort of video comparing what I believe is a real one showing the following:

I bought some SIBA fuses on eBay recently for an old Fluke I picked up for $20.

I'm not intending to use the meter on AC mains but it would be interesting to know if the fuses are fake. 

[EEVblog]

I'm now selling genuine ASTM fuses in a mixed pack.

[CustomEngineerer]

I'm now selling genuine ASTM fuses in a mixed pack.

At a genuine price?

[james_s]

How about cutting open a few samples of suspected counterfeit fuses to see what's inside them? I'd be curious to see just how junky they are. I'm sure someone could make a reasonable quality approximation of the real deal for a lot less but I'm betting most of the fakes are just a cheap fuse element inside a cardboard or plastic tube.

[joeqsmith]

I'm now selling genuine ASTM fuses in a mixed pack.

I remember you mentioning it and I looked at your Amazon store but did not see them listed. 

How about cutting open a few samples of suspected counterfeit fuses to see what's inside them? I'd be curious to see just how junky they are. I'm sure someone could make a reasonable quality approximation of the real deal for a lot less but I'm betting most of the fakes are just a cheap fuse element inside a cardboard or plastic tube.

I bought a few and as I mentioned I plan to check the filler of the one after I check the trip current.   I think depending what I see there, I may hook one up to the transient generator.  Not very scientific but if there is no filler we may get a small bang. 

Even Asia Fuse are filled...

[Fungus]

if there is no filler we may get a small bang. 

Not impossible, but ... they'd have to be total cheapskates to not put filler in them. You can get sand for free almost anywhere in the world.

[joeqsmith]

if there is no filler we may get a small bang. 

Not impossible, but ... they'd have to be total cheapskates to not put filler in them. You can get sand for free almost anywhere in the world.

Nothing is free.  First they have to dig, sift, clean, dry and then install it.  That's a lot of cost... 

[joeqsmith]

Picture showing what I believe is a real SIBA and the one I just bought.  All of the SIBA fuses that have came in meters I have, have this same LOGO.  Someone had posted the SIBA now has a factory in China.  Did the logo change for that factory?

[Fungus]

Looking closely, I'm fairly sure mine are fake. The printing is well below German standards.

Oh, well.



It would be interesting to know how the fakes perform. There's no reason why they can't do a reasonable job - it's just meltable metal and sand.

[Alex P]

I'm now selling genuine ASTM fuses in a mixed pack.

Shameless plug: https://www.eevblog.com/product/multimeter-fuse-pack/

[joeqsmith]

I think I may have acquired some fake SIBA branded fuses.  I was thinking to make some sort of video comparing what I believe is a real one showing the following:

I bought some SIBA fuses on eBay recently for an old Fluke I picked up for $20.

I'm not intending to use the meter on AC mains but it would be interesting to know if the fuses are fake. 

I have to believe you are not alone in your idea that if you don't use the meter on mains that there's no problem.  I can see this actually being the majority. 

I have enough data to say that the fuse is a counterfeit or SIBA has no quality control.  I think rather run the second fuse on the half cycle transient generator where most people will think, that's not something I will ever do, I will run a low current time test on it.  Something that hobbyist's could experience.     

The OEM parts have time rating curves.  Say the real fuse will blow in a maximum of 10ms with 4X over the trip current applied and the cloned fuse takes 100ms to open.  The circuit the fuse is protecting may become damaged.

So no half cycle line test. 

[Fungus]

I'm now selling genuine ASTM fuses in a mixed pack.

Shameless plug: https://www.eevblog.com/product/multimeter-fuse-pack/

Is there any way to get just a couple of the big ones?

[joeqsmith]

[SeanB]

Years ago at the RS distributors i was shown a Fluke 77 meter they had recieved back from the Corporation, simply marked as "Faulty". Now, with the leads missing the probes on both, and being simply bare wire ends,  you might be suspicious, given that the meter case looked like a truck had driven over it a few times, in mud, on a concrete road, and it was missing the holster completely.

However, it did power on, and the display simply showed some random segments, and faded away. Shop owner took it apart, and we both looked inside. Never seen a copper coated case before, and even odder was this was on top of the foil shielding there as well, Battery was fine, checked on another meter and load tested with battery tester, and it passed with flying colours. Fuses were both perfect, and original ones as well. PCB however was slightly different, the entire copper track area around the input side was totally missing, leaving only components there on the landings, and with clear PCB where the traces were.

Turned out that some sparktrician had tried to use this meter to measure the primary side of an 11kV substation transformer, and this had blown the 30A fuse in the supply line. Sparky survived mostly undamaged ( well, no more damage added), but this 2 month old meter was not covered under warranty. Never Done Correctly simply put in a purchase order for a new one.

[Jester]

IMO, it depends what you are using the meter to measure. If your working with a high energy circuit, for example a 600V industrial distribution circuit, you would be foolish to use anything but the originally specified fuse. On the other hand if all your work is limited to repair of 3.3V, 15A power supplies and you blow a fuse once a week one could argue your foolish to spend $37 on a fuse when a $1 fuse will suffice.

[joeqsmith]

Years ago at the RS distributors i was shown a Fluke 77 meter they had recieved back from the Corporation, simply marked as "Faulty". Now, with the leads missing the probes on both, and being simply bare wire ends,  you might be suspicious, given that the meter case looked like a truck had driven over it a few times, in mud, on a concrete road, and it was missing the holster completely.

However, it did power on, and the display simply showed some random segments, and faded away. Shop owner took it apart, and we both looked inside. Never seen a copper coated case before, and even odder was this was on top of the foil shielding there as well, Battery was fine, checked on another meter and load tested with battery tester, and it passed with flying colours. Fuses were both perfect, and original ones as well. PCB however was slightly different, the entire copper track area around the input side was totally missing, leaving only components there on the landings, and with clear PCB where the traces were.

Turned out that some sparktrician had tried to use this meter to measure the primary side of an 11kV substation transformer, and this had blown the 30A fuse in the supply line. Sparky survived mostly undamaged ( well, no more damage added), but this 2 month old meter was not covered under warranty. Never Done Correctly simply put in a purchase order for a new one.

That  job would be dangerous enough, but I imagine the life span is pretty short when you are untrained and stupid.  What's a little strange is I would have thought in most counties you would not just walk up and make a measurement like this. 

[joeqsmith]

IMO, it depends what you are using the meter to measure. If your working with a high energy circuit, for example a 600V industrial distribution circuit, you would be foolish to use anything but the originally specified fuse. On the other hand if all your work is limited to repair of 3.3V, 15A power supplies and you blow a fuse once a week one could argue your foolish to spend $37 on a fuse when a $1 fuse will suffice.

If were only using the meter on the bench with the voltages and currents you mention and I knew that that meter would never be used by anyone but me, I would rather buy a fuse from a major brand with the same or faster trip times and not an HRC counterfeit.  The cost should be reasonable.   

If this was for a disposable meter I may not care if a counterfeit fuse damaged it.  There is no way I would risk damaging a $100+ meter to save $5 to $15 on a fuse.   

Then again if I was blowing a fuse in my handheld meter once a week, I would most likely find a hobby that better suited me.

[rsjsouza]

I know fluke did offer a 5 pack of fuses for about $25.

Digikey sells 5-pack of 440mA and 11A for US$25.30 and US$46.50 respectively.

1) Sometimes you're an idiot and measure Volts while the meter is connected in Amps. Flukes will beep at you. But you won't hear that in all use cases. ^{This will cause a plant-wide blackout when you're fixing the 10kV load sharing.}
2) When you're doing repeated work. This will be a point of mistakes.
(...)

Not all Fluke meters beep at you. I am that kind of idiot that do this from time to time - thus this is one of the reasons why I now prefer meters that at least beep - otherwise I yank the fuse out of them.

[biggerpizza]

I am so happy to know Digikey sells 440mA fluke fuse for 9USD only. However 1minutes later, I figured out it's for US market only.
Digikey Australia sells the same thing for 119AUD.
What a rip off.

[Whales]

I can't see any 440mA fuses on Digikey, can you share a link?

It's probably worth going for a similar fuse (+/-20% or so from the 440mA original is probably fine) from a good brand and similar time rating.

[J-R]

Come on guys, think before you post!  I typed "440ma fuse" into the DigiKey search box, hit Enter, then clicked the first Top Result and got all the links being discussed.

Double whammy, the two DigiKey links in rsjsouza previous post still work!

But to answer the question, the 119AUD listing states Bulk Package and if you scroll down it's for quantity 10.

[boggis the cat]

Digikey Australia sells the same thing for 119AUD.
What a rip off.

Also try RS and Element14.  Usually one or the other will have them at a lower price.

[Whales]

I got zero hits earlier, now the search is finding them under speciality fuses 

[BeBuLamar]

Some here said that don't use the precious Fluke meters on the main then what do you use to measure 480VAC if you don't use the Fluke?

[rsjsouza]

Some here said that don't use the precious Fluke meters on the main then what do you use to measure 480VAC if you don't use the Fluke?

They probably use the M830B...

YOLO, right?

[SteveLTN]

I'm trying to buy some fuses here. And I'm in China. Certainly I want to avoid fake ones.

Interestingly though, I found Fluke China is actually selling the 11Amp ones at 55 CNY each, which is about 8 USD. Other sellers (Fluke authorised sellers) are selling them cheaper, tapping $3.5-$5 range.

Now I'm curious. If the cheap sub $10 fuses are counterfeit ones, how would Fluke themselves be selling them? Maybe the cheaper ones on Ebay aren't counterfeit ones after all.

[wraper]

I'm trying to buy some fuses here. And I'm in China. Certainly I want to avoid fake ones.

Interestingly though, I found Fluke China is actually selling the 11Amp ones at 55 CNY each, which is about 8 USD. Other sellers (Fluke authorised sellers) are selling them cheaper, tapping $3.5-$5 range.

Now I'm curious. If the cheap sub $10 fuses are counterfeit ones, how would Fluke themselves be selling them? Maybe the cheaper ones on Ebay aren't counterfeit ones after all.

$10 is just a normal price you can get them for. $3.5 most likely is fake. You can get genuine stuff for a bit more than $5 though https://item.szlcsc.com/5734030.html?mro=1

[jonpaul]

Assume Everything from Communist China is counterfeit  and fake

Get genuine parts of safety or work is invloved.

j