The Security Industry Association (SIA) has released initial recommendations to avoid the potential alarm system problems related to digital subscriber lines (DSL). (See April 2000, “Hot Newswire,” page 14.)
According to SIA, the following practices will help ensure that alarm systems operate properly in locations where DSL has been installed.
– Split the DSL path from the rest of the telephone wiring in the premises.
– Run the non-DSL path through the alarm panel to the rest of the analog devices (as in a regular alarm system installation).
– Place the low-pass filter in the non-DSL path prior to the alarm panel.
To provide the DSL/non-DSL split, either an existing wire that runs only to the desired wall jack can be used for the DSL path, or a splitter and a new run of wire can be used to create the DSL path. At least one telco is working on an inline device that will enable a compatible DSL connection without the need for the splitter.
Because the wiring configuration is so important, dealers should advise their customers that if they decide to get DSL service they should contact their alarm dealer. SIA plans to issue further recommendations to the alarm industry on this and related telecommunications issues based on the findings of its investigations.
