Read these 7 Switches and Switchboards Tips tips to make your life smarter, better, faster and wiser. Each tip is approved by our Editors and created by expert writers so great we call them Gurus. LifeTips is the place to go when you need to know about Circuit Breakers tips and hundreds of other topics.
Semiconductor fuses are used, as the name implies, in semiconductor products to prevent damage from overloads. They aren't usually found in consumer products, but rather in solid state relays and other semiconductor applications. Semiconductor fuses are used because of their fast reaction times. Semiconductors can be sensitive to conditions that cause a fuse to blow; to prevent damage to the system a quick arrest of the overload is needed. Semiconductor fuses limit short circuit times drastically. They are often designed using a series of silver strips--the higher the amp rating, the greater the number of strips. The silver is housed in a tube or ceramic enclosure filled with sand made from pure quartz. Under normal conditions, the silver remains intact, but melts the moment a fault is detected.
An electric switchboard is a series of panels used to send electricity from one source to another. Whether the primary source of power is the electric company, a series of generators or other power supplies, the amount of power sent out by the electric switchboard must be the same as the incoming power supply. Just as in the home, people are safeguarded against electrical shocks from electric switchboards by a series of circuit breakers or fuses. Inside each electric switchboard there is a set of busbars much like inside the electrical panel of your circuit breaker box at home. The busbars are big strips of conductive metal such as copper, and the relay switches are attached. As with any electrical panel, the power supply to the busbars must be turned off before any maintenance work can be done inside the electric switchboard.
A momentary switch is one that acts much like any other switch--it starts or stops current, but only a single position connects with live current. Once the switch is thrown or the button is pushed, it snaps back to the original position. If you throw the switch by pushing it to the "up" position, it makes contact and snaps back to the lower position instead of remaining up.
Momentary switches can be used to turn on a circuit, turn one off, or activate momentarily. A good example of the momentary function is in the standard doorbell. When the switch is pushed on, it rings the bell until the switch returns to the original position. You wouldn't want the doorbell to ring constantly once the switch is activated, as it's only meant to work long enough to get your attention. The momentary switches found in average doorbells ring for as long as there is current, but some switches activate the doorbell for a specified length of time before the system "times out" and must be initiated again.
Snap switches are a kind of switch designed to be activated with a specific type of action, either snapping to the left or right or by a spring operated snapping mechanism. In order to activate the circuit (or deactivate it depending on how the snap switches are installed) a specific type of force and motion is required. Snap switches are often used in panels for door locks, motor control, timers and other functions. They are designed so that accidental activation of the circuit is much less likely due to the motion required to activate the unit.
With an ordinary push button or switch, accidental contact may cause the circuit to activate; with snap switches the accidental contact doesn't equal unintended results unless the force and direction of the contact are equivalent to intentional activation. There are three kinds of general-use snap switches; one type made specifically for AC, another combining AC and DC capabilities.
A fuse holder is a clip or receptacle designed to contain the fuse and make it easy to replace. One of the most common types of fuse holder is found in guitar amplifiers. These are found either at the rear of the amplifier or within the cabinet. If a fuse is blown during a rehearsal or performance, it is simple to replace the fuse quickly with little downtime, as long as the amplifier is completely unplugged before the fuse is replaced.
Fuse holders are often designed to eliminate the need for special tools. A fuse that is simple to remove or easy to install means shorter downtime and safer replacement. No matter what kind of fuse or fuse holders are used, it is very important to insure there is no current to the circuit before attempting a replacement. In addition to the usual electrical hazards before and during installation including accidental contact with live wires or terminals, once the fuse is in place, the user should not be in contact with the fuse itself when it is exposed to current.
An LED toggle switch is a simple switch with an LED light in the handle of the switch which indicates the presence of current when it is turned on. When the light is on, the unit it is attached to is turned on. LED toggle switches are commonly found in automobiles and motorcycles. If you install an after-market lighting display on a licence plate, for example, the LED toggle switch is used to activate those lights or turn them off. Since you can't physically see the lights connected to the license plate, you can observe the LED toggle switch to make sure the lights are actually on.
If you turn the LED toggle switch to the "on" position and you don't see a light, it is an indicator that something is wrong and the lights are not working. LED toggle switches may have multiple lights installed to indicate different levels of use. If you have an LED toggle switch that can activate two rows of lights, the toggle may give you the option of lighting one row, the alternate row, or both together. It all depends on the type of LED toggle switch you purchase.
An electronics fuse is basically what the name implies; a fuse used in electronic circuits to prevent damage to the system because of an electrical overload. In an integrated circuit, these fuses are used to "trim" an analog circuit. This is done by adjusting the resistance of the path of electrical current. Did you know electronics fuses are used in the RAM chips of your computer? They can be used to enable "redundant memory" when there are defective sectors in the RAM. Electronics fuses are also used in military hardware such as missiles and other explosives. Electronics fuses can be used as "fast-blow" or "slow-blow" versions. They are adjustable and can be set to serve a particular function such as limiting the amount of current used.