Garage security and safety concerns can both be met by garage door sensors. Safety issues such as a door closing on a small child or pet can be avoided by installing sensors. Security issues can also be addressed – there are garage door sensors that function as garage door alarms, alerting the homeowner to potential intruders.
The simplest function of sensors used in conjunction with the garage door is to allow a closing door to stop its downward action and to reverse direction, thus avoiding the potential for crushing or otherwise trapping a person or object in the door’s path. The security feature found on protective sensors is patently obvious – an alarm alerts if the garage door is raised, which may be an indication of an intruder.
There are perhaps as many types of garage door sensors on the market as there are garage door types, and they are often used together with automatic garage door openers. These range from infrared and radio-frequency sensors to those using optical laser light. The sensors operate on a simple principle – a signal is sent from a sending unit posted on one side of a garage door. The receiver, whether it is an antenna to pick up infrared or radio signals, or a photoelectric sensor that is targeted by an optical laser, functions as a “trip wire”. If the line of communication is broken between the receiver and the emitter (as in a person walking through a laser beam while the door is in its downward motion) then the contact signals the door to stop and reverse. Another type of sensor is one that responds to pressure. A sensor is mounted on the bottom edge of the garage door; when the door’s edge comes into contact with an obstruction, the sensor sends a signal that reverses the door. Most sensors are mounted roughly six inches above the garage floor, and it is the range above this that is most in need of monitoring.
A less obvious, but equally important, safety feature that can be had in these sensors is a carbon monoxide detector. In garages where there is no garage exhaust fan installed, this feature lets the garage ventilation work on its own. The sensor detects a certain concentration of CO (preset), and when that level is reached the door opens to allow fresh air to circulate and scrub the CO out of the garage.
Installing garage door sensors is not a difficult job but it does require attention to detail. Most sensors work with beams that run parallel to the garage floor and are mounted on the door’s side rails. Others mount to the doors themselves. Both communicate either with a hard wire or by a wireless signal to the automatic garage door opener. In order for the sensors to work properly, the installer must take proper care to align the garage door sensors, ensuring a clear and undeflected signal from the emitter to reach the receiver. Most newer doors are required by law to have these installed at the factory. If retrofitting an older door, however, it might be wise to have a professional technician do the work to insure proper operation. Existing sensors should never be bypassed.
Furthermore, although there are many companies making garage door sensors, a few of the more durable tool and home repair companies offer them as well, such as Craftsman® and Stanley®. Most major retailers such as Wal-Mart and Amazon carry many varieties. Pricing for these can be inexpensive. Smaller models that use batteries are about the least costly, and many satisfactory units can be purchased for as little as $20. The more features desired (such as the security alarm feature that signals when the door is open when it should not be) add cost to the unit. Costs can exceed $250 dependent upon the level of options wanted. Regardless of cost, the peace of mind is worth the price.