How many telephone lines are required for a burglar alarm system with a UL central station certificate?

A burglar alarm system with a UL (Underwriters Laboratories) central station certificate does not require any telephone lines for its operation because it is not reliant on traditional telephone services for communication. Instead, these systems often utilize alternative communication methods such as cellular connections or internet-based protocols to transmit alarm signals to the central monitoring station.

The purpose of the UL certification is to ensure that the alarm system meets certain standards for performance and reliability, which can be achieved without the use of standard telephone lines. Thus, it is possible for a certified system to operate solely through digital means, making it unnecessary to have dedicated phone lines.