The first time I measure mA current with my personal Fluke meter.... - Electronic Circuits Projects Diagrams Free

speakerguy79 · 10th June 2008, 11:38 PM

...I blow the dang fuse.

Remind me to use different color jumper wire for power and ground next time. It took the brunt of a 12V unregulated wall-wart. I'm hoping the fuse is the only thing that went.

crutschow · 11th June 2008, 12:24 AM

At least it wasn't across the 110V line.

RODALCO · 11th June 2008, 03:55 AM

And fit the correct type fuse as specified by the manufacturer.

That will give you the correct interrupting capabilty in case of an other operator error and protects the meter.

Your Fluke meter should be OK.

speakerguy79 · 11th June 2008, 04:08 AM

I've got the exact Fluke replacement P/N in my cart at Digikey. They're five dollars and change.

rjvh · 11th June 2008, 05:07 AM

Quote:

Originally Posted by speakerguy79

They're five dollars and change.

better that than to buy a new meter

Hero999 · 13th June 2008, 04:37 PM

I don't know about flukes but all the meters I've seen use pretty generic 250mA fast blow cartridge fuses. I can't remember exactly what size, 25mm springs to mind though.

speakerguy79 · 13th June 2008, 08:23 PM

The Fluke fuse is Fluke PN 943121. It's manufactured for them by Bussman. The Bussman PN printed on the fuse is DMM-44/100, but searching that PN won't get you anything on Bussman's site or Digikey either. The only near equivalent I could find on Bussman's site is the Bussman DMM-B-44/100. My blown fuse looks identical to this one minus the "B".

Digi-Key - 283-2495-ND (Cooper/Bussmann - DMM-B-44/100)

If you buy the Fluke PN (you have to search for it using Fluke's PN 943121) at Digikey it's 5.95. If you buy the DMM-B-44/100 it's $35. I put the Fluke one in my cart

Hero999 · 13th June 2008, 09:38 PM

It's $35 for a pack of 100, how many do you get for 5.95?

mister_e · 13th June 2008, 09:56 PM

No they're really 35$ each @ Digikey. Standard package is the minimum package size Digi-Key receives from the manufacturer.

Hope the Fluke replacement is the same... 30$ less, that worth a try

I replaced the same fuse in my own Fluke 189 awhile back... can't remember the price i paid though.

speakerguy79 · 13th June 2008, 10:33 PM

Yeah, this is for a 177. I wonder if the $35 fuse just has a different label or if the 'B' means something.

Hero999 · 13th June 2008, 10:43 PM

Oh, I see.
Digi-Key Help Screen

That sounds a lot for a small fuse, some multimeters are cheaper than that.

mister_e · 14th June 2008, 12:13 AM

Maybe a mistake somewhere, however, looking elsewhere for DMM-44/100 as part number, you'll find them for around 5$.. which is normal... better than 35$ that's for sure.

First Google hit
Fluke Fuse DMM 44/100 > Fuse, 440 mA 1000V, 10x35mm, FA Fuse DMM 44/100 Fluke Test Equipment

Allied
Allied Electronics

And so on.

As speakerguy79 said, maybe the B mean something... Mouser sale them 20$...

Hero999 · 14th June 2008, 10:58 AM

Have you looked on eBay?

There again, this might be a bad idea is for safety reasons you want to avoid cheap Chinese crap.

speakerguy79 · 14th June 2008, 01:58 PM

If it were a cheaper meter I might, but saving a few bucks on a fuse for a $200 meter isn't my thing.

Sceadwian · 14th June 2008, 09:09 PM

crustshow, 110 isn't so bad. I just blew a 7 amp fuse (and four diodes) when I plugged a bridge rectifier rated at only 1amp in backwards. Nearby light dimmed and there are some nice little metal balls (vaporized fuse wire that condensed) on the glass. Aside from the very mild audible pop that's what they're designed to do. The only reason I can think for a fuse being extra expensive is if the fuse itself is being used as the shunt for the current reading, but the only meter I've ever taken apart had an internal shunt seperate from the fuse.

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10th June 2008, 11:38 PM	(permalink)
speakerguy79	The first time I measure mA current with my personal Fluke meter.... ...I blow the dang fuse. Remind me to use different color jumper wire for power and ground next time. It took the brunt of a 12V unregulated wall-wart. I'm hoping the fuse is the only thing that went.

11th June 2008, 12:24 AM	(permalink)
crutschow	At least it wasn't across the 110V line. __________________ Carl

11th June 2008, 03:55 AM	(permalink)
RODALCO	Fuse And fit the correct type fuse as specified by the manufacturer. That will give you the correct interrupting capabilty in case of an other operator error and protects the meter. Your Fluke meter should be OK. __________________ There are more ways to get to Rome. Electricity, Electric clocks, Meters and Trains are great.

11th June 2008, 04:08 AM	(permalink)
speakerguy79	I've got the exact Fluke replacement P/N in my cart at Digikey. They're five dollars and change.

13th June 2008, 04:37 PM	(permalink)
Hero999	I don't know about flukes but all the meters I've seen use pretty generic 250mA fast blow cartridge fuses. I can't remember exactly what size, 25mm springs to mind though. __________________ I also post at the following sites: http://www.stop-microsoft.org http://www.heated-debates.com Screen name: Aloone_Jonez

13th June 2008, 08:23 PM	(permalink)
speakerguy79	The Fluke fuse is Fluke PN 943121. It's manufactured for them by Bussman. The Bussman PN printed on the fuse is DMM-44/100, but searching that PN won't get you anything on Bussman's site or Digikey either. The only near equivalent I could find on Bussman's site is the Bussman DMM-B-44/100. My blown fuse looks identical to this one minus the "B". Digi-Key - 283-2495-ND (Cooper/Bussmann - DMM-B-44/100) If you buy the Fluke PN (you have to search for it using Fluke's PN 943121) at Digikey it's 5.95. If you buy the DMM-B-44/100 it's $35. I put the Fluke one in my cart Last edited by speakerguy79; 13th June 2008 at 08:24 PM.

13th June 2008, 09:38 PM	(permalink)
Hero999	It's $35 for a pack of 100, how many do you get for 5.95? __________________ I also post at the following sites: http://www.stop-microsoft.org http://www.heated-debates.com Screen name: Aloone_Jonez

13th June 2008, 09:56 PM	(permalink)
mister_e	No they're really 35$ each @ Digikey. Standard package is the minimum package size Digi-Key receives from the manufacturer. Hope the Fluke replacement is the same... 30$ less, that worth a try I replaced the same fuse in my own Fluke 189 awhile back... can't remember the price i paid though. __________________ Steve ______________________ info@mister-e.org www.mister-e.org Last edited by mister_e; 13th June 2008 at 09:58 PM.

13th June 2008, 10:33 PM	(permalink)
speakerguy79	Yeah, this is for a 177. I wonder if the $35 fuse just has a different label or if the 'B' means something.

13th June 2008, 10:43 PM	(permalink)
Hero999	Oh, I see. Digi-Key Help Screen That sounds a lot for a small fuse, some multimeters are cheaper than that. __________________ I also post at the following sites: http://www.stop-microsoft.org http://www.heated-debates.com Screen name: Aloone_Jonez

14th June 2008, 12:13 AM	(permalink)
mister_e	Maybe a mistake somewhere, however, looking elsewhere for DMM-44/100 as part number, you'll find them for around 5$.. which is normal... better than 35$ that's for sure. First Google hit Fluke Fuse DMM 44/100 > Fuse, 440 mA 1000V, 10x35mm, FA Fuse DMM 44/100 Fluke Test Equipment Allied Allied Electronics And so on. As speakerguy79 said, maybe the B mean something... Mouser sale them 20$... __________________ Steve ______________________ info@mister-e.org www.mister-e.org Last edited by mister_e; 14th June 2008 at 12:18 AM.

14th June 2008, 10:58 AM	(permalink)
Hero999	Have you looked on eBay? There again, this might be a bad idea is for safety reasons you want to avoid cheap Chinese crap. __________________ I also post at the following sites: http://www.stop-microsoft.org http://www.heated-debates.com Screen name: Aloone_Jonez

14th June 2008, 01:58 PM	(permalink)
speakerguy79	If it were a cheaper meter I might, but saving a few bucks on a fuse for a $200 meter isn't my thing.

14th June 2008, 09:09 PM	(permalink)
Sceadwian	crustshow, 110 isn't so bad. I just blew a 7 amp fuse (and four diodes) when I plugged a bridge rectifier rated at only 1amp in backwards. Nearby light dimmed and there are some nice little metal balls (vaporized fuse wire that condensed) on the glass. Aside from the very mild audible pop that's what they're designed to do. The only reason I can think for a fuse being extra expensive is if the fuse itself is being used as the shunt for the current reading, but the only meter I've ever taken apart had an internal shunt seperate from the fuse. __________________ "Because I be what I be. I would tell you what you want to know if I could, mum, but I be a cat, and no cat anywhere ever gave anyone a straight answer, har har."