o que é DPS

Discover the SPD and its advantages!

o que é DPS

Discover what SPD is and how it works protecting the electrical network:

Problems with electricity can create huge losses to companies, industries in general, condominiums and even houses. Electrical surges burn machinery and equipments, besides destroying motors that are activated by electricity. An SPD protects business assets against these anomalies, which are common in electrical networks, being very useful for preventive action, mainly in places with lots of machinery and different electrical equipment using the same network.

In this post, we’ll explain the meaning of the acronym SPD and what the main objective of this device is. Besides, we’ll point the main information concerning the term, so that you understand how it works, the types available in the market, how to install, what mistake should be avoided when mounting it, and advantages of using the solution.

Would you like to know what SPD is? Keep reading and stay tuned!

Understand what SPD, Surge Protector Device is

The acronym SPD stands for Surge Protector Device, meaning they protect equipment against surges.

They’re devices that detect anomalies and overtensions in the electrical network. This tool is known by engineers and electricians, who recommend their use to protecvt:

  • Transformers;
  • Household appliances;
  • LED street lighting;
  • LED industrial lighting;
  • Telecommunication lines;
  • Solar energy panels;
  • Company pipes;
  • Building switchboards
  • Electric machines, equipment and motors.

The devices protect from lightings and common surges in overcharges. They are like circuit breakers which turn off when there is an atmospheric electric discharge or when there is a problem in the electric line.

Understand how the SPD works

The SPD detects and rapidly detours the surge to the grounding system, in a way the circuit breaker won’t even feel the escape. The device is connected to the ground wire on one side and the phase wire on the other, closing a circuit that won’t damage the electrical setup of the place. However, they need to be connected to disconnection circuit breakers.

SPD types

In the market, it is possible to find three SPD classes and all of the are indispensable for the safety of the population. Class I concerns devices that drain partial currents from atmospheric rays A classe I diz respeito aos dispositivos que drenam correntes parciais dos raios atmosféricos, which is used in rural and peripheral urban areas.

Class II refers to devices that drain from inducted currents in buildings. Finally, class III concerns useful devices for fine protection of equiment connected to the electric, pohone or data networks. The last class is very important, once it avoids sever accidents relatred to electricity.

Where and when to install SPD

The SPD installing process is crucial to protect the devices. If implementation is inadequate, the device is uselessto protect the electrical system. It is recommended to count on the support of a specialized professional who is able to perfor the job..

The installer needs to know electricity concepts, understand about Vp/ef or equivalent protection level, which considers tension drop at the conductor terminals (V1 / V2) and the SPD tension (Vp). The used formulas for SPD with varistor are the following:

  • Vp/ef = Vp + V1 + V2;
  • DeltaV = V1 + V2;
  • Vp/ef = Vp + Delta V.

As for the SPD with encapsulated spark gap technology, we must verify the biggest value between Vp and Delta V, considering that the connection drop happens after its ignition. Besides, it is necessary to grant that the devices and the ground wire are connected to the equipotential bar linked to the SPD, and not to any stem.

The SPD’s input and output wires must have at max 20 inches long in case they belong to class I. If the connections are bigger, they can be done through the SPD’s terminals, to eliminate Delta V’s contribution, meaning “Delta V. (D1 + D2 ≤ 20in)”.

To reduce inductance between the wires, the professional can  Para reduzir a indutância entre os cabos, the professional can twist the conductor wires and use shielded cables. This technique works if the ground wire connected to the SPD is connected to the equipotential bar and goes through a dedicated conduit. Seems hard? Well, let’s make it simpler!

The SPD’s installation can be planned at the architectural project to consider all the electrical structure. The tool needs to be installed alongside a disconnection tool. It must be placed before the general circuit breaker to ensure protection, because if it fails, the circuit breaker keeps functional.

However, the SPD can also be installed  after the general circuit breaker. In this case, if the circuit breaker fails, the SPD is deactivated and the energy consumption interrupted.

So in this sense, installing the SPD inside the general switchboard or at the entrance of the electrical network is advised. There are, still, individual SPDs, which are useful for a single equipment, plugged into an outlet.

Find out the most common mistake when installing an SPD

The most common mistakes when installing SPDs are related to very long connections, when the device is connected to any equipotential bar. There is an inductance that makes the tension elevate and causes inductive coupling, which cancels the SPD’s effect.

Take advantage of the SPD

The SPD should be adopted as a safety measzure to avoid surges at the facilities and extend the rated life of equipment, machinery and LED luminaires, controlling the power factor. Lightining strikes, blackouts and energy peaks are unpredicatable and can generate unnecessary costs to companies.

The use of the device prevents even bigger disasters.

See below the main benefits benefits using the SPD:

  • Protection of electrical installations;
  • Maintenance of equipment operation;
  • Reduction of damage caused by lightning.
  • Protection of equipment such as LED lighting and machinery;

Now you know what SPD is and its advantages. Big companies use this device to protect their assets and minimize losses that interfere with the progress of the business. Know how to pick the right model for your enterprise and keep all your devices in perfect conditions.

Now that you are convinced that SX Lighting will offer you the best lighting,  click here and request specialized support.

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