The use of protective devices in electrical installations is mandatory and has been increasing more and more, among them the DR (residual differential device). Electrical installations that have this protection device, cannot have installed any shower model, because under certain conditions the DR protection device can trip, understand why this can happen, which shower can be installed and what makes the DR trip when the shower is turned on. Come on, guys!
Shower and DR.
The combination of DR and shower is often the subject of discussions between electricians, being one of the “excuses” against the use of the protective device in the shower facilities, as according to some electricians the shower causes “problems”, the DR is constantly disarming.
According to standard NBR – 5410 in item 220.127.116.11.2 it is mandatory to use a high sensitivity residual differential device as additional protection in places that have showers or bathtubs, therefore the use of the protection device is mandatory in bathrooms.
What is DR?
To know why the DR is disarming due to the shower on, we must know what it is for and how a DR works.
In a very succinct way, the DR is a protection device used in electrical installations that allows the circuit to be de-energized whenever there is a current leak higher than that supported by the DR, having as its main objective the protection of users, when there is an electric shock, he, the DR disarms immediately and this significantly minimizes the risks of electric shock and by perceiving this leakage of current the device does not allow unnecessary use of energy by leakage of current, thus avoiding the increase in the value of the energy bill.
Causes of DR activation.
There are several cases where the DR will be disarming and can mention some, such as: when the shower is not compatible, factory defect in the shower resistance, as there may be a failure in the insulation of the resistance or some internal defect of the DR.
Ordinary showers are not compatible with DR because their resistances are not shielded, that is, they are bare, the fact that the resistance is common causes a small leakage of electric current, this is because the resistance is in direct contact with water, this is also one of the reasons why the shower faucet can shock you.
In some regions, the fact of having a higher index of salts dissolved in water ends up enhancing its conductivity, with a much greater current leak, being detected by the protection device.
It is good to take into account that all equipment has its time of use, which is no different with showers, so the shower even when it is compatible with the dr and has been in use for a long time can have worn in the insulation of the resistance, causing the protection device acts on the circuit, even if the resistance is not burned.
DR-compatible showers are manufactured with armored resistors, for this reason, they should not disarm the residual differential device, this resistance model has this definition since the turns are surrounded by a layer of magnesium oxide and a metallic material, in addition to having an insulating material at the end of each terminal, so the resistance has no direct contact with water, so there is no possibility to have a current leakage towards the water.
In the case of some of these problems that were mentioned, change the shower if it is new, if the problem remains to call a professional in the areas, where he will be able to identify the error.