The electrical outbreak is a phenomenon that can cause the burning of electrical and electronic devices, these outbreaks occur due to several factors, such as, for example, the rays that fall on the electrical network, a departure of large electric motors and other anomalies that can occur in the installations. electrical. This is the main reason why we should always use a DPS surge protection device.
Size is the importance of the surge protection device, which Companhia Paulista de Força e Luz (CPFL), points out that from then on requests for new connections made will have to be installed in the DPS standards of energy input. So we will explain better its operation and some information that the dealership provides.
We emphasize that these data being represented in this article are specifications according to Companhia Paulista de Força e Luz, but it is not the only concessionaire that recommends or obliges the use of surge protection devices installed in the input standard, as is the case of CELESC.
With regard to the surge protection device, it is important to understand that when an outbreak occurs, the DPS diverts this outbreak to the grounding system, this occurs in a fraction of seconds and is usually so fast, that the circuit breaker is not able to detect this leakage. grounding, this being the reason that phase and ground are connected in the DPS.
The functioning of the DPS and the way it is installed really looks like it is closing a short circuit between phase and ground, but in fact when the surge protection device detects an outbreak, it does close a short between phase and ground, but that it takes place in a controlled manner, in an extremely short period so that it is not harmful to the installation.
The biggest problem with DPS is when it reaches the end of its useful life, that is, when its internal circuit is no longer able to make this quick shutdown to earth. In some cases when the protection device burns, it closes a permanent short between phase and ground, which ends up creating a huge problem.
To solve this, the NBR 5410 standard regulates the use of protective devices for the DPS, these circuit breakers are called disconnection devices. Then, in the event of a permanent short due to the burning of the surge protection device, the circuit breaker will trip and prevent the leakage of current to earth.
According to CPFL and NBR 5410:
It is mandatory to install the DPS in the standard of entry of the consumer in all new installations, in accordance with the requirements of NBR 5410. This procedure aims at the cancellation of overvoltages caused, for example, atmospheric phenomena, thus avoiding eventual damages that can be caused to equipment, as well as preserving people’s safety.
This same protection is mandatory by NBR 5410, for equipment that receives external signal lines, such as telephony, cable TV, data communication and others.
When the objective is protection against atmospheric overvoltages transmitted by the external power line, as well as protection against switching overvoltages, the DPS must be installed close to the line entry point in the building or in the main distribution board (QDP) , located as close as possible to the entry point;
When the objective is to protect against surges caused by direct lightning strikes on or near the building, the surge protection devices must be installed at the entry point of the line in the building;
Additional DPS may be required to protect sensitive equipment. These surge protection devices must be coordinated with the upstream and downstream DPS, that is, before and after.
The installation location must necessarily be after and outside the measurement compartment, its installation and dimensioning must follow the following installation criteria:
For the protection of the building against atmospheric surges originating from the electric network, the location for the installation of the DPS must be in the same structure in which the electric power input box is housed, as defined in NBR 5410.
A single set of surge protection devices installed at the source of the installation can protect multiple circuits. The DPS must be of type II class, with fixation on rails (DIN) or claws (NEMA).
In order to correctly size the surge protection device there are two fundamental factors, which is its maximum operating voltage and maximum discharge current. So we show in the video below how to choose the ideal DPS for your installation, this line of devices meets all the specifications of the standards, and can be used both in the input standard and in the circuit distribution board (QDC).
For this we have a selection guide from Schneider that is very simple to use, and it is not necessary to install the application on the computer and can also be used on the cell phone, being a great differential for the electrician. This wanted to show the exact DPS for the establishment, in addition to indicating the disconnect circuit breaker according to the surge protection device, being all protection devices of the Easy9 line.
We finish this article here and we hope to have helped you to clear all doubts about the mandatory DPS in the entry standards! If you still have any questions on this subject, leave it in the comments and we will respond.