You know all the steps to perform electrical installation of an electric tap, these taps are becoming very popular for heating water. In this article, we will cover the step by step of installing an electric tap respecting NBR 5410. We will answer frequently asked questions like this, can we connect an electric tap to the common outlet? We will also cover concepts such as safety in the installation and operation of the electric tap. Let’s get to know.
What is an electric faucet
Electric taps were created to solve problems in the cleaning routine of modern homes since not all homes have water heating. These installations are made, either for more comfort on cold days or because hot water has a much greater potential to eliminate grease, thus helping the user to perform the cleaning task in less time, more easily and with less use of Chemicals.
The houses became more bold and modern, in this way the electric taps also started to present themselves in a bold and modern design, this device also became a highly sought after decorative item. Applications that were previously only on an industrial scale, restaurant kitchens, companies and industries started to be used in common homes.
Operation of an electric tap
Electric taps are very similar to electric showers, where we use a network-powered resistor to heat water. Let’s look at the principle of operation of electric taps with the details of the operation:
- When opening the valve, water enters the electric tap box, the internal pressure of the water accumulated inside the tap triggering a diaphragm.
- The diaphragm when pressed by the water moves by pressing an electrical contact inside the electric tap. At this moment the flow of electric current is released, energizing the internal resistance by turning on the electric tap.
- The electric current runs through the resistance, causing it to heat up, so the water that is close to that resistance is heated by heat exchange.
- At the end of the use, the valve is closed, the water loses pressure in the electric tap box, causing the diaphragm to return to its original condition, interrupting the electrical contact, consequently interrupting the passage of electric current.
Installing an electric tap
The electric tap is a device with high energy consumption, they can be found on the market in the supply voltages of 110V and 220V, as they are electrical devices that involve the use of water in their operation, their electrical installation must be well performed to avoid risks such as electric shock and short circuit.
To perform the installation the first step is to identify the maximum power of the equipment, so we can perform the calculation of the current in the circuit and dimension the cables and protection. For example, we will use a Lorenzzetti electric tap – VERS 2200V / 5500W.
As we are dealing with a purely resistive circuit, there is no need for more complex calculations since the power factor is 1, so we do not consider incidence in the reactive power circuit, so all energy consumed in the circuit is active power.
Note that the maximum current for the circuit was 25A, so we cannot use a mixed circuit for the tap, much less use a kitchen outlet for this installation. According to the NBR 5410 Standard in the item: “18.104.22.168 Any point of use foreseen to supply, exclusively or virtually dedicated, equipment with rated current greater than 10 A must constitute an independent circuit.”
In this way, appliances with greater electrical power 1200W at 127V and 2200W at 220V need to be supplied with an independent circuit for better functioning and safety of the installation. In the case of installing the electric tap, if the residence does not have the individual circuit, as described, it will be necessary to install the circuit by an electrician.
Now that we know the current demand of the electric tap we need to dimension the best section of the electric cable, so that it can conduct the current without suffering heating or wear of the insulation for this we can use the table 36 available in NBR 5410:
Checking the table presented in column B1- which deals with PVC pipes embedded in masonry, in the session of 2 charged conductors (as it is a 220V installation), we verify that the 2.5 mm² cable can conduct a maximum current of 24 Thus, it does not meet our project. We then move on to the next 4mm² cable, which can conduct a maximum current of 32A, so the cable can handle our electrical installation.
To size the circuit protection breaker , we need to use a safety factor, to do this simply multiply the nominal current of the equipment by 1.15, after the calculation we can find the market breaker closest to the value found (Never use a breaker below the calculated one) :
We found a current of 29 A, the circuit breaker closest to the current found will be the two-phase 32A circuit breaker. We will use a C – DIM curve circuit breaker to protect our circuit.
According to standard NBR 5410, the circuit must have a protective earth cable, since the device will be working directly with water, this installation of the protective wiring is essential for the safety of people and equipment, preventing the electric current in case of failure travel people or structures. By convection the ground conductors are green or green with yellow, for our circuit the grounding conductor must be a cable of at least 2.5 mm², to offer good protection to the circuit.
The connection of the electric tap to the installation cables must be made through a porcelain connector, it allows heat dissipation and also avoids bad contact in the connection, in this way we will avoid problems such as stiffening the electrical cables, heating the connection and we will not have the insulation of the cable melting and wearing as is common in cases of bad contact in the connection.
Using these tips you will be able to perform the correct installation of the electric tap with an excellent level of safety, providing a safe use of the equipment for the users and also a better useful life for the devices. In case of doubts always remember to consult a professional.