Autronica manual call point with SelfVerify function. For use in harsh environmental conditions. EEx n-version for use in zone 2.Up to 2 x M20 cable glands. The BF-501/N is a manual call point for use in harsh environmental conditions, for use in hazardous area zone 2. It must be connected to the BSD- 310/N loop driver, but does not require an isolator/barrier unit. The call point has been designed for use with Autronica's interactive fire alarm system called AutroSafe and consists of the SelfVerify function. This function ensures the highest grade of reliability and the lowest degree of manual testing, because all units comprising this function are automatically self-tested once every 24 hours. The high IP degree and mechanical strength of the enclosure make the call point suitable for outdoor applications in industrial, maritime and offshore installations. The BF-501/N must be installed according to local regulations, which normally means along escape routes, landings and exits.