Warning - your house and your equipment are in danger!
Smart Alarm cares about your safety. And the struggle our customers have been having in protecting their houses against electrical problems has prompted us to offer additional services and products, to ensure the total security of our customers' homes.
This topic concerns two typical problems in Thailand, both of them difficult to solve without professional help.
Did you know that disconnecting one cable in the unlocked electricity cabinet on the street in front of your house can damage all the electrical equipment in your house?
Thailand has an unstable power network, but it also has a very dangerous way of supplying power into
homes. Disconnecting one cable at the meter on the street is enough to generate high over-voltages in your house, which can damage all connected electrical devices or even cause a fire.
Most customers, project managers and electricians are unaware that circuit breakers, UPSs, surge protectors and ground leak systems are not effective against the removal of only one cable. They have been taught that electricity needs closed circuits and that removing cables can only stop the curren and will protect and not cause damage. This is unfortunately not the case in your house, as will now be explained:
Most houses use a three-phase electricity system in a star configuration. This consists of four wires (three main lines and one neutral line), with voltages of 230V between the neutral and main lines and 380V between the main lines. In the case of symmetrical loads the zero line can be cut without any problem, but in all domestic applications the electrical devices are connected to the different phases with no concern to keep the load symmetrical, and the zero line functions as a way to keep the phases in balance when carrying a current. Cutting or opening this line creates an abnormal and dangerous situation, supplying voltages of up to 380V instead of 220V and in the worst case peak voltages of up to 656V. It is important to understand that, depending on the load, the current can still remain low but the high voltage can damage your TV or computer equipment. No circuit breaker will stop overvoltage if the current remains lower than a 10 or 20-amp fuse.
Smart Alarm is offering over-voltage breakers with digital output. They can work stand-alone and are connected to your Smart Alarm Superior security system, which will warn you locally and remotely when any problem occurs. Logging the problem can help to improve and force the supplier to take action.
The Smart Alarm Monitoring Room can now follow up your power system 24 hours a day and immediately contact the supplier when any problem occurs.
The Smart Alarm Superior security system, in combination with an interrupter, can protect, warn, log and monitor when the voltage or frequency is too high or too low.
Did you know there are eight million lightning strikes per day, and a direct hit generates currents up to 150,000 Amperes and voltages up to 100-500,000 volts?
European countries experience between two and eight lightning strikes per square kilometre each year, but in subtropical and tropical climates this goes up to between 30 and 70 strikes per square kilometre every year.
These figures should convince you that the risk in Thailand is a substantial
one. You also have to understand that surge blocks and UPS devices are not meant to stop lightning strikes. They can handle short and small over-voltages on the net, but that's it. Lightning power has many ways to infiltrate your electrical system. Galvanic, inductive and capacitive coupling can all generate high voltages and currents in your electrical equipment.
To protect yourself and your equipment you should ALWAYS have a grounding and lightning system that connects the lightning rod on your roof with the ground. This should be done in a professional way and checked with a special meter. If not it is useless and offers no guarantee at all. If the resistance or inductance to ground is too high the lightning current will choose other ways.
Even with the best lightning system, 50% of the energy can still enter your home. Devices like lightning arresters are required to stop the remaining power of the lightning strike. All buildings need one or more arresters depending on their size.
UPDATE: We now offer RCD (Residual Current Device) protection to prevent electrocution from faulty electrical appliances. Click here for more details.
Please contact us for any advice about electrical or electronic security issues.
