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Medium-voltage fuses may have liquid-filled envelopes to assist in the extinguishing of the arc. Medium-voltage fuses rated for a few thousand volts are never used on low voltage circuits, because of their cost and because they cannot properly clear the circuit when operating at very low voltages. Surface-mount technology "chip type" fuses feature few or no markings, what are electric cables making identification very difficult. Fuses can be built with different sized enclosures to prevent interchange of different ratings of fuse. Semi-enclosed fuses are fuse wire carriers in which the fusible wire itself can be replaced. Some blade-type terminals are held by spring clips. External trip indicator - similar function to striker pin, but can be externally attached (using clips) to a compatible fuse. Fuse packages may include a rejection feature such as a pin, slot, or tab, which prevents interchange of otherwise similar appearing fuses. Similar appearing fuses may have significantly different properties, identified by their markings. For other loads, power consumption may stay the same. In general, losses are estimated from the discrepancy between power produced (as reported by power plants) and power sold; the difference constitutes transmission and distribution losses, assuming no utility theft occurs. For transmission systems with low power factor, losses are higher than for systems with high power factor.

One example of a long DC transmission line is the Pacific DC Intertie located in the Western United States. One important property of the insulation which affects the current-carrying capacity of the wire is the maximum conductor temperature. High rupture capacity fuses may be rated to interrupt current of 120 kA. Phase wire in a circuit may be any color other than green, gray, or white (whether these are solid colors or stripes). The sockets for this plug are rated at (and limited to) 200 mA. In a residential setting, one study reported "limited evidence of carcinogenicity in humans and less than sufficient evidence for carcinogenicity in experimental animals", in particular, childhood leukemia, associated with average exposure to residential power-frequency magnetic field above 0.3 μT (3 mG) to 0.4 μT (4 mG). Connecting fuses in series does not increase the rated voltage of the combination, nor of any one fuse.

Voltage rating of the fuse. Current rating of the fuse. Some cartridge fuses are manufactured with end caps of different sizes to prevent accidental insertion of the wrong fuse rating in a holder, giving them a bottle shape. Most fuses are marked on the body or end caps with markings that indicate their ratings. Cartridge (ferrule) fuses have a cylindrical body terminated with metal end caps. Element window - a small window built into the fuse body to provide visual indication of a blown element. A fuse rated for 1 A at 25 °C may conduct up to 10% or 20% more current at −40 °C and may open at 80% of its rated value at 100 °C. Plasma inside the glass tube may continue to conduct current until the current diminishes to the point where the plasma becomes a non-conducting gas. For example, a glass tube fuse rated at 32 volts would not reliably interrupt current from a voltage source of 120 or 230 V. If a 32 V fuse attempts to interrupt the 120 or 230 V source, an arc may result. Rated voltage should be higher than the maximum voltage source it would have to disconnect. Once current is applied, resistance and voltage drop of a fuse will constantly grow with the rise of its operating temperature until the fuse finally reaches thermal equilibrium.

Indicating pin or striker pin - extends out of the fuse cap when the element is blown. Glass cartridge and plug fuses allow direct inspection of the fusible element. Automotive glass fuses were made in different lengths, to prevent high-rated fuses being installed in a circuit intended for a lower rating. While glass fuses have the advantage of a fuse element visible for inspection purposes, they have a low breaking capacity (interrupting rating), which generally restricts them to applications of 15 A or less at 250 VAC. The voltage drop should be taken into account, particularly when using a fuse in low-voltage applications. There is a direct relationship between a fuse's cold resistance and its voltage drop value. Ambient temperature will change a fuse's operational parameters. In some countries, because of the high fault current available where these fuses are used, local regulations may permit only trained personnel to change these fuses. Operating values will vary with each fuse family and are provided in manufacturer data sheets. Some varieties of HRC fuse include special handling features.