| Today, with the rising problem of violent crime, a | | | | one, as a burglar can cut the wires on the open circuit |
| security alarm system or a burglar alarm may be your | | | | fairly easily. |
| best solution to protect your family and valuables. | | | | Some open and closed circuit systems use a magnet |
| While many homes and businesses already have | | | | embedded in the door or window that lines up with a |
| these security alarms systems in place, many people | | | | switch. Others use a spring-driven switch. There are |
| do not. Why? Is it too expensive for the average | | | | also the switches that are little buttons that are |
| home owner, perhaps? But, on the other hand, what | | | | pressed by the pressure of the closed door or |
| value can you place on safety? These can be difficult | | | | window and released when it is opened. |
| questions for the average person. Let's take a closer | | | | How do interior security alarm systems work? |
| look at security alarm systems and see if we can | | | | While circuit alarms can work fairly well to keep an |
| reach a solution to these and other questions. | | | | intruder out, what do you do if one gets past the circuit |
| How do external Security alarm systems work? | | | | alarms and gets inside? Motion detectors are probably |
| The simplest security alarm systems work on a | | | | your best defense against an intruder who gets inside. |
| "broken" circuit concept. These alarms are built into an | | | | There are several different types of motion detectors |
| entrance way, like a door or window, and the way | | | | in the world. You see them at work every time you go |
| they work is very simple. Electrical current must have | | | | to the grocery store. They open the door for you. The |
| a path to flow through. If you break the path, the | | | | door works on a radar based motion detector. The |
| charge is broken and the current stops. In a closed | | | | little box you see above the door sends out a |
| circuit system, the path that the electricity travels on is | | | | microwave signal or ultrasonic sound waves. These |
| closed when a door or window is closed or shut. This | | | | units then wait for the waves to reflect off of |
| means that the electricity can continue to flow from | | | | something, usually you, and bounce back. When they |
| one side to the other. If the door or window is opened, | | | | bounce off of you, it displaces the reflection in a |
| it breaks the path the electricity is traveling on. This | | | | disturbed pattern and it then opens the door. With this |
| signals an alarm to go off. Letting you know a door or | | | | type of security alarm system, the box is in the room |
| window has been opened. | | | | and when the pattern is disturbed it send a signal to |
| In an open circuit system, the opposite holds true. | | | | set off the alarm. |
| When you open a door or window with this system it | | | | There are many different security alarm systems on |
| closes the system or flow of electricity and the alarm | | | | the market. Some can be had for around $10 as a DIY |
| will go off. Letting you know a door or window is open. | | | | project, while others require a specialist to install. The |
| Perhaps, by someone you were not expecting. You | | | | choice is yours on which you choose. |
| may want to use a closed circuit, rather then an open | | | | |