How many circuits should an installation have

How many circuits should an electrical installation have? Is there a maximum or the minimum number of circuits in the electrical installation? In this article, the World of Electrical answers these questions.

Electric circuit

The electrical circuit is one or more closed paths in which the electrical current travels. Every functional electrical circuit is composed of a source of electrical voltage, where there is a difference in electrical potential. The second element of a circuit is a load that will consume electrical energy and transforms it into another usable energy.

Finally, we have the electrical conductors (electrical cables), which are responsible for conducting the electric current between the source that produces it and the load that consumes it. The circuit can also have load control and control components, such as a switch to turn the circuit lamp on and off.

Electrical Installation

The electrical installation is composed of the components of the electrical connections, responsible for making the connection between the source of electrical energy and the electrical loads. In low voltage electrical installations, the generating source comes from the concessionaire and the charges are the household appliances and electronics that we connect to the outlets.

The electrical installation can be divided into the following parts:

  • The infrastructure of the electrical installation: Are the conduits, passage boxes, meter box, cable fasteners, cable trays, supports etc.
  • Measurement and protection: It consists of all meters, circuit breakers, fuses and relays that monitor and protect electrical installations.
  • Cabling: Conductors are responsible for connecting sources to electrical loads, such as electrical and electronic equipment, motors, etc.
  • Control: The control part is the switches for the lighting system, sensors for automation or systems for controlling a pool pump. Its function is to turn the loads on and off.

How many circuits can you have in the installation?

A very common question regarding the circuits of installation is whether there is a number of circuits defined by rule for an installation. To clarify any doubts, we should always consult the NBR 5410 standard. The NBR 5410 standard has some sections that talk about the division of the installation.

The first item of the division section of the installation is 4.2.5.1, note in the image below that item 4.2.5.1 says that: “The installation must be divided into as many circuits as necessary, and each circuit must be designed so that it can be sectioned without risk of inadvertent feedback through another circuit. ”

Item 4.2.5.1 of the NBR 5410 standard.

Another item of the standard that talks about the division of the installation are 4.2.5.5, note in the image below that item 4.2.5.5 says that: “Terminal circuits must be individualized by the function of the user equipment they supply. In particular, separate end circuits must be provided for lighting points and for outlet points. ”