Contact sensor

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A contact sensor is a device used in the burglar alarm industry to detect the opening and closing of doors and windows. It is a small, wireless device that is installed on the frame of a door or window and a magnet is installed on the corresponding moving part. When the door or window is opened, the magnet moves away from the sensor, triggering an alarm. Contact sensors are an essential component of any burglar alarm system as they provide an early warning of a potential break-in.

In the commercial and residential burglar alarm industry, contact sensors are used to protect homes, businesses, and other properties from intruders. They are typically installed on all exterior doors and windows, as well as any interior doors that lead to high-value areas such as safes or server rooms. Contact sensors can also be used to monitor the opening and closing of cabinets, drawers, and other storage areas.

CGSmith is a business and residential security system installation and monitoring company based out of the Milwaukee WI area. As a leading provider of security solutions, CGSmith understands the importance of contact sensors in protecting homes and businesses from intruders. They offer a wide range of contact sensors that are designed to meet the needs of their customers, including wireless sensors that can be easily installed without the need for drilling or wiring.

If you are interested in learning more about contact sensors and how they can help protect your home or business, CGSmith is here to help. Their team of experienced security professionals can provide you with all the information you need to make an informed decision about your security needs. To learn more, simply visit the Contact Us page on their website and fill out the form. A member of their team will be in touch with you shortly to answer any questions you may have and help you get started on the path to a more secure future.


1. What is a contact sensor in a burglar alarm system?

A contact sensor is a device that is used in burglar alarm systems to detect when a door or window is opened or closed. It consists of two parts: a magnet and a switch. The magnet is placed on the door or window, and the switch is placed on the frame. When the door or window is opened, the magnet moves away from the switch, triggering the alarm.

2. How do contact sensors work?

Contact sensors work by using a magnetic field to detect when a door or window is opened or closed. When the magnet and switch are in close proximity, the magnetic field is strong enough to keep the switch closed. When the magnet moves away from the switch, the magnetic field weakens, and the switch opens, triggering the alarm.

3. Where should contact sensors be placed in a home?

Contact sensors should be placed on all doors and windows that are accessible from the outside. This includes front and back doors, sliding glass doors, and ground-level windows. It is also a good idea to place contact sensors on any windows that are easily accessible from a roof or balcony. Additionally, contact sensors can be placed on interior doors, such as those leading to a garage or basement, to provide an extra layer of security.

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