electrical safety product
It is very similar to a surge protector in that it senses an sudden increase in voltage and/or current and quickly diverts the circuit to ground or isolates the attached devices.
A lightning arrester is to protect equipment from getting damaged from a lightening charge. Electricity will go to the nearest ground and the best ground or negative side - which is the ground you are standing on. The positive side + is in the sky, the higher you go the higher the charge ( in the millions of volts ). Air is the best insulator for high voltage so you don't get electrocuted when standing under a high voltage power line, or in a airplane. The + and the - are trying to equalize so the negative side runs along the ground looking for the positive electrons, and the positive electrons are looking for the negative, like a magnet so when they get close enough, the negative charge (amps) goes up to the positive charge burning the air and making a path so the positive charge can get to the earth. If you ever watch lighting-stroke you will see a light flash go up before the positive charge comes to the earth. Lightning arresters protect your computer, TV, and all the electrical equipment you have. When hair stands up on the back of your neck, get out of there.
I assume you mean a surge arrester not a lightning conductor. They are main 2 types. One is simply 2 contacts spaced apart so that a voltage increase above that designed will spark across the contacts and be dissipated. The other, and better type, uses metal oxide but basically does the same thing. It conducts when the voltage goes above the design level. The surge arrester protects from lightning or other over voltage spikes such as switching transients. They are not designed to dissipate large amounts of power so can be destroyed by other types of over voltage such as transformer winding fault
In a way they are the same thing, but the lightning arrester works better. A regular surge protector protects against sudden surges in the power line much like a circuit breaker. It may not work on lightning because lightning has enough power to sometimes jump past that break in the circuit--to plan for lighning you need something much better, and it should redirect that energy back to ground rather than just breaking the circuit.
A lightning rod, sometimes called a lightning arrester is something you mount on top of your house. It is a pointed long metal rod (or several of them) that is mounted on the roof so that it is the highest object. It is connected via a heavy metal cable to a ground rod which is driven into the ground nearby. It will attract any lightning bolt and dissipate it to ground. You may be talking about a surge protector, an electronic device usually mounted in outlet strips, that provides protection to voltage surges and spikes, which can be caused by a nearby lightning strike, or by inductive loads switching off. Surge protectors are usually varistors, which are power devices that have an V-I characteristic that causes them to shunt voltage much above the normal line voltage to ground.
