MAKING SENSE OF PRODUCT SPECS
DIFFERENT FREQUENCIES FOR DIFFERENT NEEDS
The wavelengths generated by a system operating at 900 MHz are considerably shorter than those of a 300 to 400 MHz system, and that also contributes to the greater range of 900 MHz systems, notes Craig Dever, national sales manager for Inovonics of Louisville, Colo., a manufacturer of a 900-MHz system. “The longer the wave-length, the less ability you have to penetrate commercial buildings that are made with a lot of concrete and metal,” he explains.
Government regulations virtually ensure that interference is not a problem for products operating at 900 MHz, notes Mark Hillenburg, product architect for Springfield, Mo.-based Digital Monitoring Products (DMP). “To operate at that frequency, you have to accept interference any other system gives you, and there are certain things you can’t do,” he explains. For example, he says, “You can’t lock onto one channel and talk on it all day long.”
Advances in components also have played a role, some manufacturers say. “There have been improvements in electronic components on transmit power and receive sensitivity,” says Mike DeMille, director of product management for Toronto-based DSC. Components involved include both chipsets and discrete components, he adds. Some advances in wireless range have led to the creation of new products. Honeywell, for example, offers a wireless motion detector designed for outdoor use that has extended range.
Hybrid Systems Are Here to Stay
Many of today’s panels support a mixture of wired and wireless sensors, enabling installers to use wireless where wiring does not exist or cannot easily be installed. Manufacturers offer a wide range of wireless sensors today, including some that work outdoors, making them suitable choices for adding protection to outlying areas. And certain sensors, such as pendant alerts, are inherently wireless.
Improved communication adds to the appeal of wireless add-on sensors, which today can be individually identified by the control panel.