Protection of expensive electronic devices
Pull plugs in thunder and lightning?
By Klaus Wedekind
07/29/2022, 4:50 p.m
Looking for beeches and avoiding pastures during thunderstorms is definitely wrong and also dangerous. But what regarding the rule of unplugging televisions, computers, and other expensive electronics when there’s thunder and lightning? Is that just a myth too?
It used to be common practice to unplug the TV when a thunderstorm was approaching. There are now many other expensive and sensitive electronic devices in most homes, but many users do nothing to protect them from lightning strikes, believing that this is no longer necessary. Are they correct?
Overvoltage protection has only been mandatory for a few years
No not true. Since a transitional period expired at the latest at the end of 2018, overvoltage protection is mandatory in new buildings, among other things, if “equipment of overvoltage category I or II is installed in buildings”, which can be assumed in every residential building. However, this is not the case with older buildings and lightning rods are not required by law.
“Most houses don’t have a lightning rod on the roof, the so-called external lightning protection, which diverts the energy into the ground,” Harald Woelffle of ED Netze told the “energy service“. “If the homeowner has a satellite dish installed on the roof, lightning is likely to hit the dish first, which acts as an antenna for the lightning. Such metal objects literally attract lightning and forward it to the house installation. Then things are bad for the computers and household appliances.”
Three-level internal protection
In order to protect electrical devices, however, one needs above all internal lightning protection. He is loud Association of Electrical, Electronic & Information Technologies (VDE) divided into three levels. They are also referred to as coarse, medium and fine protection.
Level 1 are so-called lightning current arresters or overvoltage protection devices type 1 (SPD 1). They are, so to speak, the first bulwark once morest lightning currents that enter a building via water, data and other lines and are usually installed in front of the electricity meter. The coarse protection catches Allianz direct According to this, the entire energy content of the flash is reduced and the remaining residual voltage is reduced to less than 1300 to 6000 volts.
Type 2 surge protection devices, also known as surge arresters, are usually used in meter boxes or other so-called sub-distributors. The medium protection level limits the remaining overvoltage to less than 600 to 2000 volts.
Building protection is not enough
However, this remainder is still sufficient to potentially put an end to electronic devices. Noisy “PC Magazine” they only have to be able to withstand 500 volts in order to receive the mandatory CE marking. The brochure “Overvoltage protectionAccording to the Elektro+ initiative, electronic devices have a dielectric strength of at least 1,500 volts for the power supply. This means that even if there is overvoltage protection, it can be advisable to unplug valuable electrical devices when a thunderstorm approaches.
However, the unplugging method is of little use if nobody is at home when the storm comes. An alternative is type 3 protection devices. These are usually power strips with overvoltage protection. However, this fine protection is of little use if no level 1 and 2 overvoltage protection is available. In addition, in the event of lightning strikes close by, higher voltages can occur than the strips can withstand, despite upstream arresters. So when you buy one, you should make sure that you can dissipate as much electricity as possible.
Also pull data and telephone cables
If you want to protect your devices, you should not only think of the power cables. Connected internet, telephone or antenna cables can also be fatal. AVM therefore expressly advises, for example, to pull the plugs on Fritz boxes and accessories or landline telephones during thunderstorms. Alternatively, Elektro+ recommends installing a special combined arrester for communication technology in the meter cabinet.
Photovoltaic systems, heat pumps, building system technology, etc. also require special protection once morest overvoltage. Information and advice can be found in the brochure “Overvoltage protection“.
