## Sunday, July 30, 2023

ASSEMBLY and DIAGRAM - SINGLE-PHASE DISTRIBUTION BOARD

How to ASSEMBLE a 127V SINGLE-PHASE DISTRIBUTION BOARD

If you do not have the knowledge, follow this step by step that I will show, in addition to taking the first steps in the electrical area, you will indeed be able to assemble your first distribution board, known as QDC, but it is important to know some details, especially in the part of tests, but I'll talk about that later.

Assembling a QDC involves many components, from washers, cables, terminals, bars, connectors to Protection Devices.

So, much more important than setting up the board is good planning. This way we will be sure that we have made a perfect and safe assembly.

It is necessary to define the number of outlets and lighting points to suit the building. This is the only way we can define the number of circuits and the power needed to meet the entire demand of this building.

This is very simple to do, you can even use WOCA, which is a simpler electrical design web platform. We even have a video here on the channel where we show you how to make a project using this platform. I'll leave it as a video suggestion for you to watch after this video, right?

As an example, let's use the following schedule:

A simple house, with 5 rooms, where we will have 5 circuits, being:

1 - Lighting - 1X10A - 1.5mm2

2 – Living room/bedroom sockets – 1X20A – 2.5mm2

3 - Bathroom outlet - 1X20A - 2.5mm2

4 – Kitchen/laundry outlets – 1X25A – 4.0m m2

5 - Shower - 1X50A - 10.0mm2

In addition to being able to predict the quantity, cables and protections of the circuits, with this information we were also able to define the size of the QDC.

And to suit our example, we will need a qdc with the following size:

MONOPOLAR CIRCUIT BREAKER - 5 SPACES

MONOPOLAR GENERAL CIRCUIT BREAKER - 1 SPACE

BIPOLAR IDR - 2 SPACES

175V SPD – 2 SPACES (PHASE + NEUTRAL).

RESERVE CIRCUIT - 2 SPACES

So we have 5 + 1 + 2 + 2 + 2 = 12 spaces

We found QDC's in the market with a minimum size of 12 spaces, which will suit our example.

Note that I did not report the value of the general circuit breaker or the IDR. This is because it will depend on a calculation called “demand calculation” and which varies according to each energy concessionaire.

Now let's go to the next step, which is fixing the qdc. It can either be recessed, which is the frame that is bolted to the wall, or else it can be superimposed, when it is screwed to the wall.

Defining which model will be used, let's move on to our 3rd step, which is fixing the frame elements, such as the neutral and earth buses. Then start organizing the circuit cables, which should already be passed. Separate the grounding, neutral and phase conductors, using nylon clamps to join them, leaving the cables ready to be connected to the busbars and protections.

Next, let's start assembling the QDC protections. In general, we start by assembling the protections part of the qdc first and then we assemble the protections of the circuits.

Rest assured that attaching the guards to the DIN rail is simple. First we put the top part of the protection on the rail and then tighten the bottom one.

Cables passed and protections installed, it's time to make the connections. Let's start with the simplest one, which is to "crimp" the tubular terminals on the blue cables, which are intended for the neutral and then just connect these cables to the neutral bus. The same must be done with the green cables, which are the cables destined to the ground of the circuits.

A detail that some professionals overlook is to be careful not to use thicker terminals than the cable gauge. The terminals must have the same section as the cable.

Now let's connect the input power cables to the qdc general circuit breaker input. At the output of this circuit breaker, we will derive 2 cables: one of 4.0mm2 that will be connected to the SPD input and another in the same gauge as the input cable that will be connected to the DR input of the qdc. The DR phase output will be connected to the single-phase comb bus that serves the circuit breakers.

The neutral cable that comes from the standard input will be connected to the DR input and its output will be connected to the neutral bus. In this way, all circuits will be protected by the DR, including the lighting circuit.

Remembering class, always crimp the terminals. This demonstrates professionalism and care. In addition, also use washers to identify the circuits.

And finally, identify each circuit breaker, as well as the general breaker, DPS and DR. Also, and don't forget to place the warning label and the single-line diagram on the frame cover.

ASSEMBLY and DIAGRAM - SINGLE-PHASE DISTRIBUTION BOARD

How to ASSEMBLE a 127V SINGLE-PHASE DISTRIBUTION BOARD

If you do not have the knowledge, follow this step by step that I will show, in addition to taking the first steps in the electrical area, you will indeed be able to assemble your first distribution board, known as QDC, but it is important to know some details, especially in the part of tests, but I'll talk about that later.

Assembling a QDC involves many components, from washers, cables, terminals, bars, connectors to Protection Devices.

So, much more important than setting up the board is good planning. This way we will be sure that we have made a perfect and safe assembly.

It is necessary to define the number of outlets and lighting points to suit the building. This is the only way we can define the number of circuits and the power needed to meet the entire demand of this building.

This is very simple to do, you can even use WOCA, which is a simpler electrical design web platform. We even have a video here on the channel where we show you how to make a project using this platform. I'll leave it as a video suggestion for you to watch after this video, right?

As an example, let's use the following schedule:

A simple house, with 5 rooms, where we will have 5 circuits, being:

1 - Lighting - 1X10A - 1.5mm2

2 – Living room/bedroom sockets – 1X20A – 2.5mm2

3 - Bathroom outlet - 1X20A - 2.5mm2

4 – Kitchen/laundry outlets – 1X25A – 4.0m m2

5 - Shower - 1X50A - 10.0mm2

In addition to being able to predict the quantity, cables and protections of the circuits, with this information we were also able to define the size of the QDC.

And to suit our example, we will need a qdc with the following size:

MONOPOLAR CIRCUIT BREAKER - 5 SPACES

MONOPOLAR GENERAL CIRCUIT BREAKER - 1 SPACE

BIPOLAR IDR - 2 SPACES

175V SPD – 2 SPACES (PHASE + NEUTRAL).

RESERVE CIRCUIT - 2 SPACES

So we have 5 + 1 + 2 + 2 + 2 = 12 spaces

We found QDC's in the market with a minimum size of 12 spaces, which will suit our example.

Note that I did not report the value of the general circuit breaker or the IDR. This is because it will depend on a calculation called “demand calculation” and which varies according to each energy concessionaire.

Now let's go to the next step, which is fixing the qdc. It can either be recessed, which is the frame that is bolted to the wall, or else it can be superimposed, when it is screwed to the wall.

Defining which model will be used, let's move on to our 3rd step, which is fixing the frame elements, such as the neutral and earth buses. Then start organizing the circuit cables, which should already be passed. Separate the grounding, neutral and phase conductors, using nylon clamps to join them, leaving the cables ready to be connected to the busbars and protections.

Next, let's start assembling the QDC protections. In general, we start by assembling the protections part of the qdc first and then we assemble the protections of the circuits.

Rest assured that attaching the guards to the DIN rail is simple. First we put the top part of the protection on the rail and then tighten the bottom one.

Cables passed and protections installed, it's time to make the connections. Let's start with the simplest one, which is to "crimp" the tubular terminals on the blue cables, which are intended for the neutral and then just connect these cables to the neutral bus. The same must be done with the green cables, which are the cables destined to the ground of the circuits.

A detail that some professionals overlook is to be careful not to use thicker terminals than the cable gauge. The terminals must have the same section as the cable.

Now let's connect the input power cables to the qdc general circuit breaker input. At the output of this circuit breaker, we will derive 2 cables: one of 4.0mm2 that will be connected to the SPD input and another in the same gauge as the input cable that will be connected to the DR input of the qdc. The DR phase output will be connected to the single-phase comb bus that serves the circuit breakers.

The neutral cable that comes from the standard input will be connected to the DR input and its output will be connected to the neutral bus. In this way, all circuits will be protected by the DR, including the lighting circuit.

Remembering class, always crimp the terminals. This demonstrates professionalism and care. In addition, also use washers to identify the circuits.

And finally, identify each circuit breaker, as well as the general breaker, DPS and DR. Also, and don't forget to place the warning label and the single-line diagram on the frame cover.