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HP Forum Archive 16

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Fuse: I have to plead ignorance on this one
Message #1 Posted by Mike on 18 May 2006, 7:31 p.m.

I had to replace a fuse in a 9114 battery pack. I have seen these blown in quite a few packs. I replaced it with a 5A Pico fuse. But what has me stumped is the color codes on this device.

It is a non-flammable fues, with greenish background. It's marked "F" on one side and "5 A" on the other. Seems straight forward enough. But what about these color codes. I haven't found color codes for these types of fuses anywhere. It's just a curiousity to me. I was wondering if anyone has any comments on this.

Click image for larger image

Edited: 18 May 2006, 7:35 p.m.

      
Re: Fuse: I have to plead ignorance on this one
Message #2 Posted by Thibaut.be on 19 May 2006, 4:52 a.m.,
in response to message #1 by Mike

Isn't this a resistor, of 4K Ohms with a 2% tolerance ?

            
Nope! Not a resistor
Message #3 Posted by Mike on 19 May 2006, 2:21 p.m.,
in response to message #2 by Thibaut.be

It's definitely not a resistor. It's a fuse. You see my confusion. In fact, I read it the other direction and thought it was a 22 ohm resistor. I put that small resistor in and it lugged down the current so much it wouldn't run. So there is no way it would run with 4K.

I already suspected it was a fuse, but thought they might be using a resistor as a fuse. Didn't even see the 5A till I had already removed it.

The green body color was how I came to determine it was non-flammable fuse.

Edited: 19 May 2006, 2:23 p.m.

      
Re: Fuse: I have to plead ignorance on this one
Message #4 Posted by Tony Duell on 19 May 2006, 5:34 a.m.,
in response to message #1 by Mike

I think I can see a green, black, red band in that order. I would read that like a resistor (giving 50*10^2 = 5000), but in mA. So 5000mA, or 5A.

The last red band is probably specifying it's fast-blow. I don't really know, though.

            
Re: Fuse: I have to plead ignorance on this one
Message #5 Posted by Thibaut.be on 19 May 2006, 6:07 a.m.,
in response to message #4 by Tony Duell

The first band was yellow to me. In interpreted the last band as a toelranc eband.

            
Re: Fuse: I have to plead ignorance on this one
Message #6 Posted by Mike on 19 May 2006, 2:24 p.m.,
in response to message #4 by Tony Duell

Quote:
I think I can see a green, black, red band in that order. I would read that like a resistor (giving 50*10^2 = 5000), but in mA. So 5000mA, or 5A.
Could be. I was reading it as Red, Red, Black. There are 5 banded color coded resistors. And there is clearly a large space between the green and black (the other band that is missing). So I thought it would be read from the Red end first. If it was read from the green band end, there wouldn't be any space between the green and black. But the numbers you show might make sense.

Now you see my confusion.

Edited: 19 May 2006, 2:26 p.m.

                  
Re: Fuse: I have to plead ignorance on this one
Message #7 Posted by Katie Wasserman on 20 May 2006, 1:20 p.m.,
in response to message #6 by Mike

Here's the answer:

http://groups.google.com/group/rec.radio.amateur.equipment/browse_thread/thread/a984219156903e4c/d14e0083dfd7651e?lnk=st&q=small+fuse+%22colour+bands%22&rnum=1&hl=en#d14e0083dfd7651e

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