Home-owners purchasing a Home Monitored Security System can choose to have it connected to a professional company who will monitor the system for them. However, these companies charge a monthly fee but in return they have an expert team of professionals who will be doing the entire screening process. In opting to employ a security company, the security system installed in your home will be connected to the central control system of the company, where their personnel are based. This is usually through a protected telephone line. All signals transmitted from the control panel in your home will be constantly screened by the personnel at the control center to keep track of what is happening in the user's home. When a motion sensor, magnetic switch or any part of your Transfer & Top-up security system is triggered, the control panel instantly alerts the central monitoring center who will then notify the police. This means that the police are immediately dispatched to your house. The central monitoring center will also inform you via your mobile phone of the alarm, which can be helpful in cases where you are at work or away on holiday. As a backup, a password can be put in place so that unnecessary calls to the police are avoided. The central security company will first attempt to contact the home-owner and if they can provide the correct password, then there is no need to alert the police. There will be occasions when you trigger the alarm by accident, in these cases you have between thirty to forty five seconds to enter your security code into the keypad to deactivate the alarm and prevent a call being made to the police. If the phone line connecting the home security system to the central control system of the security company is tampered with, the security company will try to contact you to determine the reason why there is a problem with the signal between your home and their computers Transfer & Top-up . Because of possible connection problems between the phone line and the central control system, you must provide the security company with a mobile or cell number so that they can still reach you if the regular phone line is down. They will verify with you first that the phone line is down prior to alerting the police.