Waterflow-Actuated Initiating Devices

Sprinkler systems monitoring is the monitoring of water flow, pressure and valve positions within a sprinkler system.

  • • Sprinkler monitoring devices monitor condition variances within the sprinkler system.
  • • System Sensor product categories:
    • o Waterflow detectors
    • o Pressure switches
    • o Supervisory switches
  • • Explosion proof models are available for all System Sensor sprinkler monitoring devices.

The fire alarm system should monitor the operation of the automatic sprinkler system and other fire extinguishing and suppression systems by means of listed fire alarm initiating devices.
When the automatic sprinkler system operates, the waterflow-actuated fire alarm initiating device will initiate a fire alarm signal.

The fire alarm system should also monitor the normal standby condition of these extinguishing or suppression systems by means of listed
supervisory initiating devices. If someone closes a sprinkler system control valve or otherwise impairs the protective system, the supervisory
initiating device will cause the fire alarm system control unit to indicate a “supervisory off-normal condition.” When the valve is reopened or
the other impairment is cleared, the supervisory initiating device will cause the fire alarm system control unit to indicate a “supervisory restoration
to normal signal.”

The waterflow alarm and the supervisory initiating devices must be monitored separately to enable the differentiation between waterflow,
trouble and supervisory conditions. Generally with conventional hard-wiring systems this requires a separate zone for waterflow alarm
and one for supervisory initiating devices with the supervisory device being a “normally-open” device.

There are four basic types of automatic sprinkler systems that an alarm system may be connected to:

  • Wet Pipe
  • • Dry Pipe
  • • Pre-Action
  • • Deluge

While a vane flow switch may be used on a wet pipe system, a pressure flow switch is required for the supervision of dry pipe, pre-action and
deluge systems