Fuse rating question....T1A and GMC1A?

Discussion in 'Amp Tech Center' started by Wally, Sep 20, 2019.

  1. Wally

    Wally Telefied Ad Free Member

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    both of these are slow blow types, but what is the difference? I have searched and have not an answer?
    These are being used in a Fender 300 Bass amp on the DC heater filament circuit. It calls for T1A’s.
    Any insight is appreciated.
     
  2. Wally

    Wally Telefied Ad Free Member

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    Okay, here is what my local electronics supply fellow had to say. The T1A from Little Fuse and GMC1A from Buss Fuse are different designations by two different makers for the same fuse....a 1 amp slow blow. The only 5mm x 20mm 1A fuse that C.E Distribution had was a GMD1A. The GMD is not a slow blow but rather is a time delay fuse.
     
  3. Bendyha

    Bendyha Friend of Leo's Silver Supporter

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    upload_2019-9-20_21-7-20.png
    and the T series little fuse;

    edit: this is the right sheet i think
    upload_2019-9-20_21-45-37.png


    The GMC calls itself a medium, with the GMA being the fast version, but comparing them to the littlefuse slow-blo rating for a one amp fuse, it seems from what I can read off the graphs, that they are fairly similar....just different branding.
     
    Last edited: Sep 20, 2019
  4. Wally

    Wally Telefied Ad Free Member

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    Thanks for the insight, Bendyha.
     
  5. Wally

    Wally Telefied Ad Free Member

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    Okay, so I took a look at the GMD since I am gettting the hang of reading those curves. It seems that the GMD is closer to,the T1 than is the GMC. Is that correct? About one second for those two at 3A of draw? The GMC would go down in what...maybe .1 second.
     
  6. Bendyha

    Bendyha Friend of Leo's Silver Supporter

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    Wait a sec... it seems I had the wrong series data posted...the little fuse catalog is a stinker to get through...but this one i added after editing above, calls them slowblow, and seems more similar to the GMC.
     
  7. Bendyha

    Bendyha Friend of Leo's Silver Supporter

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    and here is the 239 series
    upload_2019-9-20_21-54-22.png
     
  8. Wally

    Wally Telefied Ad Free Member

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    Thanks, Bendyha. I appreciate you helping me out here. I now think I can read those curves. The first two hold 3A for just under a second, correct? The 239 you show holds 3A of draw at bay for almost 10 seconds???? It seems the GMC is good for this application.
     
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