Current trends in fire alarm communication technologies
The monitoring of fire alarm communications via phone lines has been the industry standard since the mid-1980s. Although telecommunications technologies have improved significantly with the evolution of the Internet, the quality of fire alarm communications has steadily declined in recent years. Following telecommunications' lead, it appears the fire industry could also seek benefit from the World Wide Web.
Calling Complications
The PSTN (public switched telephone network) was originally a network of fixed-line analog telephone systems. The pair of copper wires that ran from a central switch office to a subscriber's residence or business was referred to as a "subscriber loop". Each central office housed an enormous bank of lead acid batteries used for back-up power in the event of an outage.
Today, only the older parts of the PSTN utilize analog technology and many new telecommunications provider installations utilize digital systems. Advances in digital communications and increased use of fiber optic cable in place of copper wire have greatly benefited the likes of AT&T, Sprint and Verizon. It is much less costly for telecommunications providers to use multiplexed systems that remove the need for thousands of separate copper pairs to each subscriber. Fierce competition among service providers utilizing these technologies to offer a wider range of television, voice and Internet services is also believed to be the impetus for the rapid reduction in analog technology.
Many sorts of devices, including fire alarm control panels, primarily operate via analog signals. The original 48 DC voltage supplied by subscriber analog circuits (known in the industry as POTS or "plain old telephone system") has also declined to as little as six volts of off-hook voltage. As a result, communications between new and existing installations of both fire and security alarm panels have become particularly dicey as of late.
Boxes supplied by service providers to convert signals from digital to analog are a common "patch", but these have garnered mixed results. Unfortunately, increased incidents of trouble alarms have come about from this patch's analog to digital conversion at the subscriber end or the central office, followed by the digital to analog reconversion at the central station.
Technical Clarifications
As with any new technology, there's always trepidation about being the first to implement it. Many dealers and integrators have voiced their fear of a big learning curve associated with anything related to the Internet.
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