Replace a blown fuse with a fuse with a greater amperage rating. The fuse has an amperage rating because it is designed to be the weakest link in the circuit, protecting the electrical components. A blown fuse signifies that an excessive amount of current has entered the circuit. As long as the remaining fuses can handle the new load, there is no need to replace them. If one or more fuses begin to smoke or glow red when exposed to the air, they have been damaged by heat and should be replaced.
Higher amperage fuses can usually be found near the top of the box. Before using any old fuse, first check that it's not damaged; if so, get a new one. Fuses are usually either aluminum or cardboard. Aluminum fuses conduct electricity better but are heavier and less flexible than their cardboard counterparts. Cardboard fuses are cheaper and easier to work with but do not conduct electricity as well. Either type of fuse can be used in a power supply circuit. It's just good practice to use fuses that are equal to or greater than the expected load in case some other parts of the circuit fail. For example, if you plan to use a motor driver circuit with a 20-amp fuse, make sure that none of the other components in the circuit are rated below 20 amps.
Higher amperage fuses may be available for specific products that are known for high usage and thus high currents.
CAUTION! Never use a higher-amp fuse to replace a blown fuse. Replace the fuse with one that has the necessary amp rating. In a pinch, you can install the next-smaller-rated fuse to get by until you can buy a replacement. But don't rely on this method, as these fuses are usually not designed for continuous use at their maximum current capacity.
Fuses are generally available in increments of 10 amps, but some come in sizes as small as 1 or 2 amperes. Fuse boxes often contain several different sizes of fuse so you can always replace the old fuse before it fails and create a safer environment for your family and friends.
Higher-amperage fuses require larger terminals so they will fit inside standard fuse holders. If you have only standard-size fuse holders, then you will need separate fuse clips to secure these bigger fuses.
Also remember that if you increase the voltage on the line, it will also increase the current flow through the circuit and possibly blow another fuse before too long. So don't try to hack your way out of a problem by using higher-amp fuses if better options exist.
No, in general. Replacing a fuse with a higher-amp fuse is a dangerous idea that can result in a fire. Fuses (and circuit breakers) are designed to blow or trip before any section of the circuit reaches a harmful current level. Trying to force a larger current through a fuse will just burn it out faster.
However, there are two exceptions where using a larger-capacity fuse makes sense. The first is if you have a weak circuit that may not be able to handle the full load of all your equipment at once. In this case, a smaller fuse in one appliance and a larger one in another would be appropriate. For example, if one of your lamps fails and leaves its power cord plugged in, you don't want to overload the other ones too.
The second exception is if you have a circuit that already has enough capacity to handle the load but still requires some extra safety margin. For example, if you have several appliances on a single circuit and one of them breaks down, you don't want to leave its power cord dangling while others continue to work properly. In this case, a larger fuse in one appliance and a smaller one in another would be appropriate.
In general, though, replacing fuses with larger ones is not a good idea because it can lead to overheating and eventual burning of the device itself.