Combined dry-pipe pre-action systems are what type of interlock systems?

Combined dry-pipe pre-action systems are what type of interlock systems?

• A. Single interlock systems
• B. Quadruple interlock systems
• C. Double interlock systems
• D. Triple interlock systems

Answer: (C)

Two independent conditions must be satisfied before water can enter the piping in combined dry-pipe pre-action systems. In this setup, a triggering event from the detecting or alarm system must occur, and then the pre-action valve must be released to admit water into the dry-pipe network. Because two distinct interlocks operate together to release water, this configuration is classified as a double interlock system. The idea is to prevent accidental discharge by requiring both a detection/trigger and a separate valve release. A single interlock would mean only one condition is needed, while triple or quadruple interlocks are more complex than what this system typically requires.

Two independent conditions must be satisfied before water can enter the piping in combined dry-pipe pre-action systems. In this setup, a triggering event from the detecting or alarm system must occur, and then the pre-action valve must be released to admit water into the dry-pipe network. Because two distinct interlocks operate together to release water, this configuration is classified as a double interlock system. The idea is to prevent accidental discharge by requiring both a detection/trigger and a separate valve release. A single interlock would mean only one condition is needed, while triple or quadruple interlocks are more complex than what this system typically requires.