Are you aware that your life is constantly at risk from your electrical appliances?

There is no problem while everything is working normally, but if an internal fault develops it can lead to the whole equipment becoming "live", which could have fatal consequences. If you touch an appliance while it is in this state, the current would pass through your body until it escapes to the ground and could result in a cardiac arrest. In Thailand not many properties have their electrical wiring protected by a "grounding" circuit and this means that any residual current from a faulty appliance cannot be safely dealt with. So to prevent this from happening, you need to install one or more RCDs.

Are there any other dangers?

There are so many accidents waiting to happen here in Thailand because of the lack of electrical expertise and the lax enforcement of regulations regarding electrical installations.

For example, not all cables are protected inside conduits which leaves them open to damage caused by rats who can chew through them and cause a short-circuit which would, at best, blow the fuse. But it could also heat up nearby materials if the leakage current is smaller than the fuse or circuit breaker rating, and this could easily cause a fire. If an exposed cable touches anything metallic, such as a water pipe for your shower, the consequences could be fatal as this type of leakage would not be detected by a breaker and would not blow a fuse.

Another area which causes concern is a very common feature in Thailand - swimming pools. This is where most accidents are likely to happen, not only drowning but death by electrocution too. A current of only 30mA can kill you and it is extremely unlikely that this would trigger a fuse, but such a small leakage can easily occur in a swimming pool area.

How? You have probably seen in the movies how somebody is murdered by throwing a hairdryer into a bathtub, but events similar to this can happen poolside, either accidentally or through negligence. For instance, a pool pump could develop an internal electrical fault which could cause the pool water to come into contact with the mains voltage. The same could happen with a transformer for low-voltage pool lights - if a fault develops it is possible that 220 volts could be delivered to the pool lights and the water. Your jacuzzi or hot-tub could also give you a shocking experience!

Incompetent electricians or your handyman neighbour can cause fatal accidents too, by installing 220V lights or placing cables or electrical equipment too close to the swimming pool. People and especially children love to splash around in a pool and it would only take a small amount of water to form a conductor from the pool to your friendly neighbourhood electrician's work to have you calling for a doctor/ambulance/hearse. If you intend to use the services of a so-called "qualified" electrician, be sure to take up references, and then have the work checked by a recognised body or authority.

Many homeowners have shower water heaters and these are also a cause for concern because there are 220V wires together with metal water pipes in the same box. An electrical fault or a leaking pipe here needs no explanation of the possible results! Again, even a dedicated circuit-breaker for the shower will have no effect in this case and a Residual Current Device is the only possible safe solution.

So, although Thailand is a lovely place to live, it can also be a very dangerous place. This is why we need to be protected by Residual Current Devices. Normal circuit breakers will trip in the event of a short-circuit but will not detect leakages. RCDs can detect the tiniest current leakages and will cut the electrical circuit at the first sign of danger. Every household and business in Thailand should have at least one RCD installed but sadly this is not the case and many people have died as a result of electrocution.

If we all had RCDs then we could rest easy, knowing that an electrical problem is not going to kill us any time soon.

So, one of these......

.....or one of these?

IMPORTANT

Smart Alarm recommends that you have at least two RCDs if you have electrical equipment in your garden, as well as in your house. If a fault develops in a garden light or an electric lawnmower, for example, you would not want the electricity cut off inside the house. Ideally, you would have one RCD for the house and another for all other outside equipment, including your pool.

Please contact us if you would like more advice.

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Unwanted nuisance tripping

If there is a disturbance in the electrical network, RCCBs or RCD blocks which are normally in the installation will trip and interrupt the circuit even if there is no real fault.

Disturbance of this kind is most commonly caused by:

• operational discharges produced by connecting or disconnecting of loads (opening or closing of protection and command devices, starting and stopping of motors, switching on and off of fluorescent lighting, etc.); if conditions in the circuit are abruptly modified, this causes temporary disturbances such as impulse voltages at high frequency;
  
  
• atmospheric discharges caused by direct or indirect lightning onto the power line; when lightning strikes, it generates an electromagnetic field which produces a transient impulse voltage in the network; this generates capacitive earthleakage in the network cables.

In these circumstances, the nuisance tripping of the residual current protection device is unwanted since it does not prevent the risks caused by direct and indirect contact. A sudden and unjustified cut-off of the power supply, on the other hand, may cause very serious problems and jeopardize the continuity of service of refrigerators, freezers, computers, lighting and air-conditioning systems, burglar alarms, data transmission systems, etc.

the solution ......

We supply a range of anti-nuisance tripping RCCBs and RCD blocks which pass the ring wave test at 0.5 µs/100 kHz and also withstand the 8/20 µs impulse with the same peak current of 3000A prescribed for selective devices. For this reason, they offer the most direct solution to the problem of unwanted tripping caused by atmospheric or operational discharges. The electronic components they are equipped with is capable of distinguishing between temporary leakage caused by network disturbances and permanent leakage caused by actual faults and only open the circuit if the latter occurs. A slight delay in the tripping time has also been introduced which nevertheless respects the safety limits imposed by the standards (tripping time at 2 I∆n ≤ 150ms). When installed in electrical circuits, they therefore prevent unwanted tripping in installations in the residential and commercial sector where continuity of service is important and, at the same time, guarantee traditional residual current protection. The RCCBs and RCD blocks are available in A and AC types and in 2P and 4P versions with rated currents of 25A and 63A. Sensitivity equal to 30mA guarantees protection against indirect contact and additional protection against direct contact.

A Residual Current Device is a generic term covering both RCCBs and RCBOs.

A Residual-Current Circuit Breaker (RCCB) is an electrical wiring device that disconnects a circuit whenever it detects that the electric current is not balanced between the energized conductor and the return neutral conductor. Such an imbalance may indicate current leakage through the body of a person who is grounded and accidentally touching the energized part of the circuit. A lethal shock can result from these conditions. RCCBs are designed to disconnect quickly enough to prevent injury caused by such shocks. They are not intended to provide protection against overcurrent (overload) or short-circuit conditions.

In the United States and Canada, a residual current device is most commonly known as a ground fault circuit interrupter (GFCI), ground fault interrupter (GFI) or an appliance leakage current interrupter (ALCI). In Australia they are sometimes known as "safety switches" or simply "RCD" and in the United Kingdom, along with circuit breakers, they can be referred to as "trips" or "trip switches".

A Residual Current Circuit Breaker with Overload protection (RCBO) combines the functions of overcurrent protection and leakage detection. An earth leakage circuit breaker (ELCB) may be a residual-current device, although an older type of voltage-operated earth leakage circuit breaker exists.