Bussman barrel fuses, BUSS 125V FM01 5A

[rogerl]

Have four fuses under the '78 201 dash on passenger side next to voltage regulator mounted on a plate labeled: radio, panel, battery (and one more I forget at the moment), are contained in screw-off fuse holders and fuses are individually labeled:

BUSS 125V FM01 5A

Two of these are burnt out (radio and panel - and I'm hoping the defunct 'panel' one is why the panel lights quit working recently ...), and am having difficulty finding replacments.  Did find this at mouser:

http://www.mouser.com/ProductDetail/Cooper-Bussmann/FM01A125V5A/?qs=KOeOmFnJLTp%2FP0P0X0rhDw%3D%3D

But there is an errant 'A' in the part number.  Can't seem to find any others.

1) Anyone have a line on this fuse, or know how the 'A' might differ?

-or-

2) If anyone else could use one, I think the link referenced above is for a pack of 10 (I need two, plus maybe two spare); PM me if you are interested in me dropping one in the mail to you.

Roger

 

[jetdriven]

Roger, I replaced both my FM01 fuses in the dimmer and yes, those are what I have.  You are going to freak out now, because 18$ is the EACH cost.  I know, I know.  60$ delivered for two fuses.   

[rogerl]

Quote: jetdriven

Roger, I replaced both my FM01 fuses in the dimmer and yes, those are what I have.  You are going to freak out now, because 18$ is the EACH cost.  I know, I know.  60$ delivered for two fuses.   

[sleepingsquirrel]

.

[FlyDave]

Roger,

Here is a thread I started on this exact subject:

http://mooneyspace.com/index.cfm?mainaction=posts&forumid=3&threadid=966

You can find them on ebay for A LOT LESS than $18/each.

The guy I bought mine from is: http://myworld.ebay.com/itguy_2002

Check with him to see if he has any.

Dave

[rogerl]

Quote: FlyDave

Roger,

Here is a thread I started on this exact subject:

http://mooneyspace.com/index.cfm?mainaction=posts&forumid=3&threadid=966

You can find them on ebay for A LOT LESS than $18/each.

The guy I bought mine from is: http://myworld.ebay.com/itguy_2002

Dave

[jwilkins]

I just ordered over $130 worth of sample fuses from different suppliers and manufacturers to determine a good substitution for these Mil Std grade fuses. There are several possibiities, all of which are under $10 and some much less.

Yes, I know I could have just ordered the fuses I need for much less (Even at $20 each which is the current price) but $20 for a fuse seems silly.

I'll post an answer in a couple weeks when I've gone through the samples. Meanwhile, if you were going to buy spares you might hold off.

Jim

 

 

[Vref]

Quote: jwilkins

I just ordered over $130 worth of sample fuses from different suppliers and manufacturers to determine a good substitution for these Mil Std grade fuses. There are several possibiities, all of which are under $10 and some much less.

Yes, I know I could have just ordered the fuses I need for much less (Even at $20 each which is the current price) but $20 for a fuse seems silly.

I'll post an answer in a couple weeks when I've gone through the samples. Meanwhile, if you were going to buy spares you might hold off.

Jim

 

 

[jwilkins]

These are a .028 in diameter by 0.25 in height cylinder with two legs or pins coming off the bottom. 

The Mil Standard spec is MIL-F-23419/01 .270" X .25" Pin Type Fuse. They are installed in a socket and the cover screws down over the fuse to protect, retain , and in some cases splash proof it. 

I'll publish some close up photos as soon as I get my samples. They are a bit fragile so I don't want to pull one out of the panel just to take a photo.  I think I can get a direct replacement commercial spec but it's still expensive. There are also pin type cartridge fuses available from Little fuse at a very reasonable price, but the diameter is slightly smaller (not an issue) the length is .040 inch longer (may be an issue) and the leads (pins) do not have the right spacing so we would need to run them through the dog-leg component prep machine to space them out. I could not find a drawing that shows the lead diameter on the Mil Spec FM01 so this may not work anyway. The pin or leg diameters must match to get good connections in the socket.

One of the things I ordered wa a pack of ten Bussman FM01 1.5 amp fuses to have samples of the correct physical dimension Bussman fuse (although only 1.5 amp rating). Here's the photos of these:

If anyone has a need for 1.5 AMP fuses (for example if you are ONLY running the clock on that circuit) let me know. I'll have lots of spares in the 1.5 A rating.

Jim

 

[N9937c]

The pin measures .039 or 1 mm.

larry

[jetdriven]

Mine in the 1977 J panel dimmer were both 5 A.  

[jwilkins]

I'll post a message when we get and check the samples but it appears that the best bet because of pin diameter will be the commercial version of the FM01. Still stupidly expensive for a fuse, but about half the cost of the Mil Spec version with the same electrical and physical specs. Once we pick a part number I'll check on quantity breaks to see if it's worth a combined purchase.

 

[jwilkins]

Update:

I have not received all the samples yet but if you need fuses NOW and can't wait, here is an alternate:

The   504-GWM-5 125V 5A I got from Mauser Electronics are a commercial equivalent to the Mil Std part number.

They look like and fit as well as the mil Std and the product specifications are the same except for not being Mil Std specification.

Mauser p/n 504-GWM-5 Cooper Bussmann BK / GWM-5

About $10 each instead of $20 and they had some in stock.

I am still hoping that one of the lower cost alternates can be used, but these are a drop-in replacement at half price.

I'll report back when I get the rest of the alternatives.

Jim

 

[Vref]

Jim, are you sure about the PN can't seem to find anything on Mouser with BK/GWM-5 thought the Mil spec BK/FM01 of course exists..?

 

[1964-M20E]

As an electrical engineer I understand the need to have the correct fuse.  One time I had a purchasing agent go buy the wrong fuse because it was cheaper and this was a special application in a hazardous atmosphere. 

However, this mess falls squarely on the shoulders of the designers for our beloved Mooneys.  The designers could have chosen a reliable low-cost readily available fuse but they did not.  The purpose of the fuse is to protect the equipment but more importantly to interrupt the flow of current to prevent a fire or electrical system meltdown and any readily available automotive fuse or glass type fuse would do just fine.  There is no need to have mil spec or exotic materials here. My $0.02

I’d search the internet high and low for an alternate.  Good luck and post the solution.

Also please post a close up pic of the fuse with a ruler in the shot to indicate scale.

[1964-M20E]

http://www.cooperindustries.com/content/dam/public/bussmann/Electrical/Resources/Data%20Sheets/Bus_Ele_DS_2058_GMW_HWA.pdf

 

Here is the link to the commercial data sheet from CooperBussman the GMW-5.  The commercial equivalent can be had for about $6 each.  FYI

 

http://www.galco.com/scripts/cgiip.exe/wa/wcat/itemdtl.r?listtype=&pnum=GMW-5-BUSS

[1964-M20E]

Links to other suppliers.  I have used Newark in the past.

http://www.newark.com/cooper-bussmann/gmw-5/fuse-5a-125v-fast-acting/dp/19K5343

http://www.mouser.com/search/ProductDetail.aspx?qs=qI%252bDxnNls1%252bv%252bBir%252bVRRJA%3D%3D

http://parts.digikey.com/1/parts/697154-fuse-5a-125v-fast-specialty-bk-gmw-5.html

 

[Vref]

Ok, thanks for the input it looks Bussman is the only manufacturer of this type of fuse?

I am looking for a European OEM supplier but I guess I will have to order from the US

rgds

 

Luc

[jwilkins]

Larry on the Red Board gave me a link to this distributor:

http://www.masterdistributors.com/products/gmw-5

They have Bussmann fuses in stock at less than $5. I did not check shipping / handling charges but they have parts in stock and say you can give them your UPS number for shipping.

There are other manufacturers of this spec fuse, but the Bussmann seems like the best direct-replacement. It is the same manufacturer as originally installed, same performance specifications, but in the commercial spec not Mil Std spec.

At $5 each for the Bussmann commercial GMW-5 I am not even going to bother with evaluating the other manufacturers samples I ordered. I'll give them to our engineer to add to his stockpile of bits and pieces.

Jim

 

 

[jwilkins]

Quote: Vref

Ok, thanks for the input it looks Bussman is the only manufacturer of this type of fuse?

I am looking for a European OEM supplier but I guess I will have to order from the US

rgds

 

Luc

[Vref]

Thanks Jim, Farnell is the European counterpart of Newark they have a lot of stuff, however some stuff (mainly Mil spec etc... ) come from the US they add about 30$ (25 euro) for every delivery not stocked in Europe....

Thanks for the effort at least I know my options now...;-)

rgds

Luc

[jetdriven]

Thats great news.  I bought two FM01 fuses from Mouser and it was about 60$ shipped.  for two fuses.   

[Vref]

Quote: jetdriven

Thats great news.  I bought two FM01 fuses from Mouser and it was about 60$ shipped.  for two fuses.   

[jwilkins]

Quote: Vref

mmmhmm ....it looks like I will check the load first (with a temp-fuse)  on the  light dim-circuit before inserting a Bussman fuse..

[mccdeuce]

Ok - bringing this back to life hopefully you guys can fix my stupidity....

I blew the radio light fuse.  While working this I decided to remove all 4 of my bussman fuses that are down there.  Thinking they were all 5 amp....  They were not.  And I don't know which one goes where....  and of course they are not labeled with their amperage.

My schematic is for a 78 J but not my specific serial number and I believe it shows only the two 5 amp fuses.

Anyone know?

The spots are BUS  BATT RADIO  INSTR