What is the purpose of a house surge protector, how much does it cost and above all how many types are there? Well, if you were looking for an article that explains all these things, Shedheads wrote a detailed installation guide for those who prefer to DIY
When lightning strikes directly a lightning rod or the roof of a gifted building of the grounding system, the lightning current is dispersed into the ground and through the power lines. The resistance of the grounding system, in dispersing the lightning current, causes an increase in the voltage of the protective conductor of earth (PE) up to several thousand volts (ohmic effect). On the other hand, the potential of the active conductors remains 230 V for the phases and zero for the neutral (remote potential of the transformer). Electrical equipment connected between the supply network and the earth can lose isolation and through it flows part of the current of the lightning, resulting in their damage.
Overvoltage arresters (also called SPD – Surge Protection Devices) are mechanisms that safeguard all our equipment against overvoltages and are characterized by two important advantages: they are economical and can also be installed in an existing system.
A surge arrester is like a container connected between L-PE and that has an infinite impedance (Z) that does not change the operation of the system. With the arrival of an overvoltage, this causes the impedance to fall to the ends of the container, allowing absorption of the generated current. The drainage of the overvoltage keeps constant the voltage at the ends of the container, and our equipment will not be damaged if the voltage is compatible with the level of immunity and insulation of the equipment.
The surge protector serves to absorb the overvoltages that can enter the electrical system and discharge them to the ground. With the advent of new technologies, now all the devices have an electronic card inside. For example, the refrigerator, the Smart TV or the air conditioning. Electronic boards are very sensitive components and it often happens that small overvoltages can damage them. This often forces us to have to replace the appliance in question. Surge Protectors minimize the risk of damage to the devices we have at home, if properly installed. Those can be of type 1 of type 2 and of type 3, let’s find out the differences.
The type 1 protector is very suitable for overcurrents caused by lightning. In fact, it means that they are particular surge protector
This second type of surge arrester is particularly suitable for overvoltages induced by maneuvers on European power grids. It would be advisable to mount the Type 2 surge arrester in the house switchboard at the base of the Type 1 arrester (which, as we saw, should be mounted immediately below the house counter), provided that there are at least 5 meters between the two.
The type 2 protectors usually consists of a varistor and a spark gap and must be mounted upstream of the differential. In case it is mounted at the base of the differential, the latter should be selective. The Type 2 arrester in case of breakage is designed so that the green varistor window turns red to let you know that the surge arrester is broken and must be replaced. The price of the type 2 arrester is around 50-70 dollars, for a quality product of course.
The Type 3 arrester is the one that goes to the base of the first two and is usually installed directly behind the socket of the appliance to guarantee a further third protection. For sure you’re wondering: But if I already have the first two, do I have to necessarily put the Third? Well, you have to know those overvoltage protectors, when good quality, “cut” the overvoltages and do not eliminate them completely. So if an overvoltage passes from the type 1 arrester, it is not resetter. Indeed, an overvoltage when walking in the cables doubles every two meters and it would therefore always be good to have a triple protection.
3 arrester has a buzzer inside that signals any eventual failure. The type 3 arrester costs about 20-25 dollars.
The connection is really very simple. In fact, the phase and the neutral must be placed in terminals L and N and then continue in the system (usually they bridge on the differential in the case of the type 2 protector). The earthing must be connected instead in the clamp that is in the inferior part of the apparatus and from which the earth cable will start that will go to connect to the knot that you have in the house.
This is certainly the easiest to install. In fact, just insert the cables in the respective terminals of the phase, neutral and grounding.
It is obviously advisable to install the protectors appropriately, that the cables with which the operation is carried out are well sized. Finally, I always ask for caution when it comes to choosing products like that, saving a few dollars could cost you a fridge or a TV that costed you dearly… So before saving on a surge arrester think well. As usual, if you need to install a surge arrester, call your installer of trust because ‘”electricity is not a joke!”
Why install surge protectors
The risk of overvoltage can expose the house, appliances, and computers to risks caused by electrical overload, which occurs in conjunction with strong summer storms.
To prevent televisions, PCs and major appliances from being damaged, sometimes even irreparable, it is important to equip themselves to prevent the problem and avoid worries in view of the departure or unpleasant surprises after returning from vacation.
Summer thunderstorms can, in fact, cause electrical disturbances causing fires in the worst case, but much more frequently damage or interrupt the power supply of our equipment and electronic systems.
Appliances, computers, but also boilers, air conditioning and security systems such as alarms become, in these weeks, more vulnerable, especially in our absence for vacation or work, and need systems that allow them to keep operating and preserve them.
In fact, 90% of household appliances are sensitive to overvoltages, and lightning is one of the main causes of damage and breakage of electrical and electronic equipment in homes, industrial plants, shops and offices.
Protecting your technology from overvoltages may seem difficult, but for those who love DIY, it may not be as difficult as it sounds. Furthermore, if the need should be immediate, you can always ask for help from those who have already installed a surge system. Defenses can be installed in no time and for relatively large spaces. With a small investment, your electrical equipment will have the best possible insurance. Especially in the areas most affected by lightning strikes such as tropical and subtropical regions, where electromagnetic storms cause damage for several million dollars per year.