Design rules of the electrical installation protection system

Design rules of the electrical installation protection system

To protect an electrical installation in a building, simple rules apply for the choice of

1. SPD(s);

2. its protection system.

For a power distribution system, the main characteristics used to define the lightning protection system and select a SPD to protect an electrical installation in a building are:

1. SPD

1.1 quantity of SPD

1.2 type

1.3level of exposure to define the SPD’s maximum discharge current Imax.

2. Short circuit protection device

2.1 maximum discharge current Imax;

2.2 short-circuit current Isc at the point of installation.

The logic diagram in the Figure 1 below illustrates this design rule.

Fig.1 – Logic diagram for selection of a protection system

The other characteristics for selection of a SPD are predefined for an electrical installation.

1. number of poles in SPD;

2. voltage protection level Up;

3. operating voltage Uc.

This sub-section Design of the electrical installation protection system describes in greater detail the criteria for selection of the protection system according to the characteristics of the installation, the equipment to be protected and the environment.

Related Posts

The Surge Protection Device (SPD)

The Surge Protection Device (SPD)

Surge Protection Devices (SPD) are used for electric power supply networks, telephone networks, and communication and automatic control buses. The Surge Protection Device (SPD) is a component of the electrical installation protection system. This device is connected in parallel on the power supply circuit of the loads that it has to protect (see Fig.1). It […]

Something About Circuit Breakers

Something About Circuit Breakers

Circuit breakers are necessary, and many experts need them to prevent circuit fire caused by short circuit current. Miniature circuit breakers are known to protect only from voltage spikes for a short period, whereas the circuit breaker protects overcurrent in the wiring. If there is over-voltage, it can damage the appliance. However, over-voltage will not […]

What is AC Surge Protective Device

What is AC Surge Protective Device

AC Surge Protective Device is an indispensable device for lightning protection of electronic equipment. Its main function is to limit the transient overvoltage that penetrates into power lines and signal transmission lines to the voltage range that the equipment or system can withstand, or to release strong lightning current to the ground, thereby protecting the protected […]