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    #81
    Re: Meters and Microamps

    Now where to get cartridge cases and do you have a beach resort that you can steal lots of sand from...

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      #82
      Re: Meters and Microamps

      Glass-cloth reinforced Melamine G9 tubing, $28/ft or $3.50 per fuse, it's easy to crimp. Cost is double that of ceramic, with USA suppliers. So this looks like the bulk of the fuse cost.

      The silica sand is around 40 grit. My math you need about 5gms each so a 50lb (22.7kg) sand bag is good for making 7,600 fuses. That's 500 fuses per $1 for sand costs.
      A 500gm roll $20 of 36SWG 0.2mm tinned copper wire 1,790m good for 35,236 fuses,. That's 1,762 fuses per $1 for wire costs.

      I looked at material costs because I want to sit on the beach sipping Mai Tai's like McAfee did before he went nuts.

      Henry Bussman patents the cartridge fuse in 1919. I looked and fuses are heavily patented and getting worse with the new HVDC need in electric cars. It might explain why they are stupid expensive from legit manufacturers.

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        #83
        Re: Meters and Microamps

        So sipping Mai Tai's on the beach is looking like it's being patented away? :-(

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          #84
          Re: Meters and Microamps

          What is truly amazing to me ... is that you two can carry on so long over fuses ...

          Comment


            #85
            Re: Meters and Microamps

            What do you expect when the cost of this type of fuse got to cost that much money I would rant have a fit over it as well because I have a Fluke meter as well I hope I never need to replace a fuse because of some careless mistake
            9 PC LCD Monitor
            6 LCD Flat Screen TV
            30 Desk Top Switching Power Supply
            10 Battery Charger Switching Power Supply for Power Tool
            6 18v Lithium Battery Power Boards for Tool Battery Packs
            1 XBox 360 Switching Power Supply and M Board
            25 Servo Drives 220/460 3 Phase
            6 De-soldering Station Switching Power Supply 1 Power Supply
            1 Dell Mother Board
            15 Computer Power Supply
            1 HP Printer Supply & Control Board * lighting finished it *


            These two repairs where found with a ESR meter...> Temp at 50*F then at 90*F the ESR reading more than 10%

            1 Over Head Crane Current Sensing Board ( VFD Failure Five Years Later )
            2 Hem Saw Computer Stack Board

            All of these had CAPs POOF
            All of the mosfet that are taken out by bad caps

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              #86
              Re: Meters and Microamps

              Come on join the fun there's 4 of us making pot shots at Bussmann, Siba, and Littelfuse shaking an angry fist at them.

              And measuring the current draw of a capacitor charging up was a mistake...

              Comment


                #87
                Re: Meters and Microamps

                OP, a replacement fuse for your Fluke 17 costs about 1/3 the price of the multimeter USD $50 at Digi-Key. It's absurdly priced for something made of a dollar of materials.

                So in come the chinese counterfeit fuses, cost a few dollars but high resistance and who knows how they work.
                We're trapped between decent quality over 10x the price, and cheap chinese counterfeits.

                Eaton Corp. stock, $55B in market cap and record profits, stock doubled in 2 years. They'd scooped up Bussmann.
                Attached Files

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                  #88
                  Re: Meters and Microamps

                  Damn. Should have bought ETN last year. Luck does not exist for me. Including a burned out fuse to replace, no less.

                  Comment


                    #89
                    Re: Meters and Microamps

                    so there are actually 3 solutions.

                    1: import SIBA fuses from europe at about $7 each.
                    2: import Australian fuses from Davy Jones in a mixed pack of 10.
                    3: buy a length of 10mm copper tube and cut it into 38mm lengths, then let natural selection take it's course.

                    Comment


                      #90
                      Re: Meters and Microamps

                      don't forget the foil wrap!

                      Also, though .223's will fit in 3AG slots, not sure if 9's will work for 5AG...

                      Comment


                        #91
                        Re: Meters and Microamps

                        There are Fluke multimeters for sale where someone bridged the fuse... really common with automotive techs on 12V systems... the shunt and bridge rectifier get burned badly, tons of smoke.

                        Siba are excellent fuses but too they're snobby to have distribution in North America.

                        I wonder if HiFi-Tuning fuses would work? Gold-plated, none of this ugly overpriced Bussmann stuff. The diode symbol contains the electrons.
                        "ceramic casing, rather than glass, for better resonance characteristics"
                        "-196ºC cryogenic immersion bath treated for maximum clarity"

                        Same price as the Bussmann
                        Attached Files

                        Comment


                          #92
                          Re: Meters and Microamps

                          Originally posted by redwire View Post
                          OP, a replacement fuse for your Fluke 17 costs about 1/3 the price of the multimeter USD $50 at Digi-Key. It's absurdly priced for something made of a dollar of materials.

                          So in come the chinese counterfeit fuses, cost a few dollars but high resistance and who knows how they work.
                          We're trapped between decent quality over 10x the price, and cheap chinese counterfeits.

                          Eaton Corp. stock, $55B in market cap and record profits, stock doubled in 2 years. They'd scooped up Bussmann.

                          Is there some kind of shortage of material or something? Or did the manufacturers form a cartel and target their evil greed on these fuses ... just to be dicks?

                          Comment


                            #93
                            Re: Meters and Microamps

                            a cartel formed a perpetual "shortage" of multimeter fuses as far as I can tell.

                            Slow blow and regular fuses markets are just fine...can even get them from hardware stores including the orange store.

                            Comment


                              #94
                              Re: Meters and Microamps

                              Originally posted by eccerr0r View Post
                              including the orange store.
                              Whatever that is ...

                              So maybe we have some sinister plot afoot .... like a modern-day Dr. Evil is building a nuke and needed all the fuses ... and we're all gonna pay the worst price if he doesn't get his one-MILLION-dollars...

                              Comment


                                #95
                                Re: Meters and Microamps

                                Originally posted by eccerr0r View Post
                                a cartel formed a perpetual "shortage" of multimeter fuses as far as I can tell.

                                Slow blow and regular fuses markets are just fine...can even get them from hardware stores including the orange store.
                                See ... I TOLD YOU something shady was going on here ...

                                Last edited by EasyGoing1; 04-05-2021, 07:54 PM.

                                Comment


                                  #96
                                  Re: Meters and Microamps

                                  Orange store = Home De(s)pot, and yes they sell 10mmx38mm slow blow fuses for building electrical use.

                                  Comment


                                    #97
                                    Re: Meters and Microamps

                                    Originally posted by eccerr0r View Post
                                    Orange store = Home De(s)pot, and yes they sell 10mmx38mm slow blow fuses for building electrical use.
                                    I actually thought Home Depot after I posted my response ... thinking ... "I wonder if he's baggin on the HD...."

                                    Comment


                                      #98
                                      Re: Meters and Microamps

                                      Well... I bought and got a 15A FF "chinese fleabay caviar" for my Fluke. Too bad it's impossible to test it for authenticity so I just stuck it in instead of having my fluke in limbo missing full functionality.

                                      Says Made in Mexico so it might be mexican caviar.

                                      Comment


                                        #99
                                        Re: Meters and Microamps

                                        You can shake it to hear the sand inside, or simply weigh it.
                                        Measure its resistance to see if the element is reasonable. For sure they sub aluminum which gives higher resistance and the fuse would run hot when operating near it's 10A limit. The (Bussmann) fuse will dissipate about 1.5W and a chinese knockoff is much worse... what's a little melted plastic around the fuse and a warped multimeter case lol.

                                        It's strange these multimeter fuses really don't blow until a lot of current is flowing - the 11A clears 50A at 5 seconds, at 20A after a few minutes.
                                        The 440mA clears 1.5A at ~3 seconds, at 1.25A after a few minutes.

                                        Comment


                                          Re: Meters and Microamps

                                          Well, they could have a little more sand to replace a little less fuse wire... or vice versa...
                                          I think I will have to take my chances.

                                          Surprised however when that 4A fuse burned almost instantly on my B&KP DMM when trying to measure capacitor charging current (which turned out to be quite large...). Capacitors are shorts after all, to charging transients...

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