A surge protector is an appliance designed to protect electrical devices from power surges and voltage spikes. Surge protectors attempt to regulate the voltage supplied to an electric device by either blocking or shorting to ground voltage above a safe threshold. Surge and noise protector. ... Surge and noise protector. ... Lightning strikes during a night-time thunderstorm. ... Voltage spikes are fast, short duration surges in the electric potential in a given circuit. ... Voltage spikes are fast, short duration surges in the electric potential in a given circuit. ... International danger high voltage symbol. ... Ground symbols The term ground or earth usually means a common return path in electrical circuits. ...
Surge protectors can be built with one or more of the following electronic components: An electronic component is a basic electronic building block packaged in a discrete form with two or more connecting leads or metallic pads. ...
A fuse burns out or a circuit breaker trips when excessive power is being consumed and fed to a device within the designed time lag and current rating. These can protect both from surges caused by the device itself and from external surges that last long enough.
An iron poor transformer can transmit AC power similar to a normal iron core transformer (although less efficiently), but will be unable to transmit sudden surges that saturate the small iron core.
A MOV is a small device that will short when presented with a voltage above its rated "clamping voltage", passing the surge to ground through the MOV rather than through the protected device, provided the current rating (joule) is not exceeded. If the surge exceeds the joule rating, the MOV will be destroyed. Even if not destoryed, MOVs also deteriorate each time they receive a voltage spike, and thus stop working after some time. Some surge protectors have a light to tell you when this stage has been reached.
A gas discharge tube is used much like a MOV, except that it relies on a trapped gas to become ionized to pass the voltage. This has the advantage of being able to pass much more power without self destructing, but with the disadvantage of reacting to the high voltage more slowly.
Devices having several outlets with surge protectors described may have all or some outlets protected. The better ones have higher ratings and offer more modes of protection against surges between the phase and neutral and grounding conductors; maybe for telephone and coax cable connections. (The best have insurance policies paying for damages from surges.)
An UPS of the flywheel type seldom pass surges. The battery variety may absorb spikes much like a capacitor acts as a low pass filter. The battery ones also have protectors described above. "On line" UPSs provide the best protection.
Series Mode surge protectors use a "surge reactor", which has the advantage of being extremely quick to react to surges and which does not generally deteriorate over time.
-1... A 2 pole MCB A circuit breaker is an automatically-operated electrical switch which is designed to protect an electrical circuit from damage caused by overload or short circuit. ... Three-phase pole-mounted step-down transformer. ... City lights viewed in a motion blurred exposure. ... For magnetic materials, saturation is the state when the material can not absorb a stronger magnetic field, such that an increase of magnetization produces no significant change in magnetic flux density. ... Zener diode symbol. ... A controller is a person or device that exercises or attempts to exercise control or influence. ... A transient voltage suppression diode is a device used to protect sensitive electronics from voltage spikes induced on connected wires. ... An uninterruptible power supply, or UPS, is a device or system that maintains a continuous supply of electric power to certain essential equipment that must not be shut down unexpectedly. ... A capacitor is a device that stores energy in the electric field created between a pair of conductors on which equal magnitude but opposite sign electric charges have been placed. ...
Surges (>10 m and <1 ms), on the other hand, have a greater energy component and it is generally this which causes the damage and charring of electronic components and appliances.
Protection of equipment connected to direct current (dc) sources or power supplies generally involves installing protection at the alternating current (ac) input to the power supply.
In larger facilities where distances between this primary protection and the equipment being protected are long, it is also good practice to provide point-of-use protection as close to the terminals of the equipment as possible.
That type of protection devices are very common on rurals installations, where there are very long lines and they are usually hanging in the air from telecom poles so they are much more prone to lightning strike surges.
To protect modem electronics, a good practice is to add protection to both sides of the line transformer: gas arrestor or VDR in the primary side of the transformer to take most of the surge and zener diodes to the secondary to take what goes through the primary protection and transformer.
When surge protectors are installed to a telephone/data communications room they are typically connected a common grounding bar which is connected to a good ground through a heavy grounding wire.
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