Login  Register
  Optifuse for your fuse needs...
Telephone:1-619-593-5050
Fax:1-619-593-5055
Email:sales@optifuse.com

    PART NUMBER Search:
HOME
PRODUCTS
CROSS REFERENCE
WEEKLY BLOG ARCHIVE
DISTRIBUTOR SEARCH
Become An OptiFuse Distributor
Become An OptiFuse Rep
Join the Optifuse Team
About OptiFuse Selection Guide Glossary of Terms Privacy Statement Site Map Contact OptiFuse
 
October 14, 2009
Common Fuse Sizes
 
 


A week doesn’t go by before I’m asked about the difference between a
1/4" x 1 1/4" fuse and a 3AG fuse.

Today I hope to be able to clear up the mystery of fuse size designations.

In the early days of fuses and automobiles there was very little standardization of products.  Manufacturers created their own individualized parts to fulfill whatever need that they had at the time.  Over the years standardization of parts began to take root and a new system was adopted for sizing fuses. 

At that point in time, the "AG system" of fuse sized was adopted (the "AG" stood for "Automotive Glass").
 
Below you will find a table of dimensions cross referencing the common AG size to the corresponding dimensions:

Reference
Length (inches)
Diameter (inches)
1 AG
5/8
0.625
1/4
0.250
2 AG
-
0.588
-
0.177
3 AG
1 1/4
1.250
1/4
0.250
4 AG
1 1/4
1.250
9/32
0.281
5 AG
1 1/2
1.500
13/32
0.406
7 AG
7/8
0.875
1/4
0.250
8 AG
1
1.000
1/4
0.250

There are few side notes to the above table.
  • The 5 AG size is also commonly called a "midget" fuse.
  • The 2 AG fuse size is easily replaced with a more common 5 x 15 mm (0.197" x 0.590")
  • Additional glass fuses sizes of 5 x 20 mm, 5 x 15 mm, and 3.6 x 10 mm are widely used throughout the world beyond North America
I hope that this helps to clear up the great fuse size mystery...too bad there wasn’t more intrigue to add to the story...

Thank you once again for your continued support of OptiFuse as we try to deliver answers to easy questions as well as the hard ones...


Jim Kalb
President
OptiFuse
jimk@optifuse.com

 

 
Home  |  Cross-Ref List   |  Products  |  Contact Us
  ;