Bussmann® BP/MDL-20 - MDL Time-Delay Tube Fuses

Automotive
Used in older-model cars, glass tube fuses today are found primarily in automotive accessory applications. The expansive Cooper Bussmann line of glass fuses includes many types and sizes in addition to those listed in this catalog.
Appliances and Consumer Electronics
Glass and ceramic tube uses are often used to protect appliances and consumer electronics. As electronic equipment becomes smaller, the circuits and components become more delicate and easily damaged. Fuses are the preferred method of protection due to their accuracy, small size and reliability. Generally, two sizes of user-replaceable fuses are found: the 1/4" x 11/4" and 5 x 20mm.
Fuse Types
There are two basic types of fuses available for appliances and consumer electronics: fast-acting or time-delay. Any replacement fuse must match the one it's replacing. In general, fast-acting fuses are a single strand of wire or strip of metal. Time-delay fuses usually have a coiled wire, a thick element wrapped in wire, or a spring. Most electronic fuses will have the voltage and amp rating stamped on the end cap. The type of fuse can generally be visually identified. Also, owner's manuals will have the correct replacement fuse generically identified. For example: "Use a 2 amp, time-delay, 250 volt fuse."
Glass and ceramic tube fuses vary by diameter and length:
AGU fuses: 13/32" x 11/2"
ABC, AGC, GBB, MDA, MDL and MDQ fuses: 1/4" x 11/4"
AGX fuses: 1/4" x 1"
GBC fuses: 1/4" x 31/32"
AGW fuses: 1/4" x 7/8"
AGA fuses: 1/4" x 5/8"
SFE fuses are 1/4" diameter and change in length as amp ratings increase
GDA, GDB, GDC, GMA, GMC and GMD fuses: 5 x 20mm
Fuse Selection Criteria
For electronic/electrical applications, fuse must be rated at 125V or better.
Voltage must match or exceed the fuse being replaced (125V for household current; 12V for auto; 24V for heavy duty).
Fuse must match required fuse characteristic - either fast-acting or time-delay.
Amp rating must match that of the original fuse.
A notation on Voltage Rating
All fuses have a voltage rating. To maintain safety, this voltage rating should not be exceeded in application, although it is acceptable to use a higher rated fuse in a lower voltage application. For example: A fuse rated for 125 volts is appropriate in household (110V) or automotive (12V), while a fuse rated for 32 volts is appropriate for automotive (12V), but not for household (125V). Always replace a fuse with one of the same or higher voltage rating.