Grounding of cast iron, acrylic and whirlpool baths

In the old days, it was not necessary to ground the house at all, but not now. For the bathroom, this question is more relevant, since water is a good conductor of electricity. Has it ever happened that, touching electrical items: washing machine, hair dryer and others, you felt a tingling sensation in your fingertips? Here's more proof of how necessary grounding is. You can make your own bathtub grounding arrangements.

Let's start with the basics. What is called grounding? It is a protection that draws the current from the body of an electrical device and drains it into the ground. Quite a number of appliances are equipped with metal grooves designed specifically for grounding.

Why is it so necessary to ground the bathtub? It's simple. Water perfectly conducts current, which means that in the bathroom there will always be a potential danger of encountering the action of electricity. And given the fact that the bathroom is full of metal pipes and various products combined with high humidity, it is imperative to ensure proper grounding to avoid accidents.

Anything made of metal that is not electrically connected: radiator, pipes, bathtub, etc., can play a cruel trick on the fuse. Once upon a time, the bathtub was grounded by connecting it to a riser: sewer or water main. But now you can not use this method! If suddenly your downstairs neighbors want to replace the metal riser with a plastic one, the grounding effect will disappear. Plus, the area of the condenser will increase many times, and this leads to even more severe consequences.

Earthing a cast iron bathtub is quite simple. Connect to its grounding circuit can be made by an ear with a hole, which the manufacturer has already pre-installed on the tub. In this ear - the so-called petal - installed bolt with washers and nuts. And to it you can already connect the ground wire. With cast iron baths of the Soviet model is a bit more complicated. There is no petal and you will have to install it yourself. To the question of whether you can connect the ground wire in this case to the feet, the categorical answer is no. There is no proper contact between the tub itself and its feet.

But there is another way to solve the grounding problem:

• Where the legs are attached to the tub, there are small offshoots coming from the tub bowl. They are designed to wedge the legs. Their surface freely allows you to drill a hole up to 1 cm deep into them;
• in this hole is tapped with a thread in which you can screw in bolts with a nut and washers. In this case, you will provide a good grounding contact of the bathtub bowl itself;
• Nothing prevents you from using the wings of the tub, in which you can easily drill a hole to a depth of 0.5 cm. But you will have to think about the length of the screw.

Do I have to earth my acrylic bathtub?

Acrylic bathtubs are becoming very popular, because the price is quite acceptable, but they are light in weight and easy to install.The basis of these baths is, as is clear, acrylic. It is a polymer, and all polymers are of the dielectric class. In other words, acrylic itself can not conduct electricity.

But it is still necessary to ground the acrylic bathtub at least for these reasons:

• Acrylic bathtubs can be made by two methods: casting and extrusion. Bathtubs made by the second method do not hold their shape well. For this reason, the manufacturer installs such tubs on steel frames. And steel is already a metal that conducts current. So, you'll have to ground the tub.
• If the bath has a bowl with a large area, then over time it will accumulate a decent electric charge. To avoid such a phenomenon, it is easier to ground the tub.

Whirlpool tubs function from an electrical outlet. Their operating voltage is usually 220 V and the frequency is 50 Hz. Hot tubs should not be used without grounding at all, as there is a very high risk of being electrocuted.

There are a number of important things to consider when grounding a hot tub:

• You can't just ground a hot tub. First, a special outlet with grounding is installed. It uses a separate plug and wire with double insulation. The plug, in fact, and acts as a grounding device. It prevents water from getting on the surface of the socket. This eliminates the situation of a short circuit, and the socket is also called moisture-proof.
• The grounding socket should be mounted on the wall, at least 30 cm high from the floor surface and at least half a meter from the sides of the hot tub. If you follow these instructions, water will not be able to enter the socket at all. It should be wired with double insulation.
• If you install not only a Jacuzzi tub, but also other electrical equipment (boiler, washing machine, etc.), then to avoid power surges, install a circuit breaker with a load up to 16 A, as well as a safety switch. Install them outside the bathroom, in a hallway or other room.
• Never use your hot tub if you have not already installed a moisture-proof socket. Grounding the hot tub through water, sewer or heating pipes is also strictly prohibited. Do not allow maintenance of a working hot tub, much less use it when there are faults in the grounding.

To do the grounding yourself, you need to choose a suitable wire. It should be chosen according to the following characteristics:

• the cable must have the necessary stiffness and a cross-sectional area of 6 sq. mm;
• the cable must have a yellow-green insulation made of PVC material;
• the length of the cable should be chosen individually. It is preferable to choose a wire from 2 m, but take into account the fact that too long cable will cause a breakthrough;
• is also important and aesthetic moment. It is unlikely that you will like it if the wires are in full view. Hide them behind panels or a screen, or run them on the side of the bathtub that is hardly visible;
• to save money, steel is usually used as a grounding electrode, but steel encased in copper, or simply copper, has a higher efficiency rating.

The grounding of the bathtub can be done according to some general rules:

• Manufacturers remember to equip all modern bathtubs with a separate grounding lug. It looks like an ear with a hole. The grounding wire is connected to this lobe;
• its bare fragment is clamped between the washers that help secure the bolt and nut;
• If the bathtub was made in the Soviet era, you must drill a hole in the foot or on the wing of the tub and in exactly the same way, using washers, bolt and nut, fix the bridge of the earth electrode.

If you do not have enough experience in electrical and installation work, it is better to contact a professional electrician who will make you grounding. But even if you've done it yourself, it's up to a professional to check that the grounding jumper works. Otherwise, you risk undesirable consequences.

There is another important point: A lot of people confuse grounding with earthing. These are slightly different things, because grounding is used only for industrial purposes, but not for domestic purposes. And the confusion stems from the fact that in apartments lately, grounding is done very often. This applies to water heaters, and to washing machines. But to conduct grounding in residential buildings is not recommended, although at the same time and is not prohibited. Just imagine that the neutral wire for some unknown reason will burn out or an electrician will accidentally connect a phase instead of zero. As a result, all your appliances will simply burn out from the excessively high voltage. Yes, and the purposes of grounding and grounding are somewhat different. Grounding is designed solely for the occurrence of a short circuit.