There are many types of security systems, including monitored, unmonitored, electric current and wireless alarm security systems. Many people use monitored security systems. If somebody enters the house, the system sends a signal to the call center via the outdoor phone line, and the call center calls the police. A disadvantage of this system is that burglars can cut the phone wires to disable the system. Also, it may take the call center and police too long to respond.
An unmonitored security system sets off a loud alarm on the inside and outside of the house when somebody tries to break in. This system counts on the owners of the house or their neighbors to call the police when the alarm is set off. Also, burglars usually try to escape as soon as possible when they encounter this security system. With this system, owners don't have to pay monthly fees for its maintenance, which is an advantage compared to the monitored system.
Homeowners can easily install wireless security systems by themselves. Buyers can choose from many types of devices, such as sensors, cameras, beams and motion detectors. A disadvantage of this system is that the owners might have to replace batteries in the devices often, which is expensive.
An electric current security system produces a steady electric current to monitor doors and windows in the house, producing a simple beeping sound when doors or windows open. The system's primary disadvantage is that electrical devices inside the house can interfere with the system, reducing its effectiveness.