F-300S Sensor Accessory

  • Flow Switch / Sensor is detects Flow / No Flow

Why do you need a Flow Switch?

Is your recirculation pump working?

Is your recirculation system at the correct flow rate?

Is your chemical pump injecting into a stopped system?

Is your filter clogged?

How Does it work?

Optional Flow Switch / Sensor is designed to detect Flow / No Flow.
A rare earth magnet is located within the red PVDF float of the new F-300 flowmeters. When the magnet passes through the Alarm Trigger Zone (Hysteresis) of the Sensor Accessory, the built-in contact closure switch sends a signal to external devices.
Note: Two alarms can be placed onto one meter to obtain both ‘Flow Switch’ and ‘Flow Sensor’ capabilities. See diagrams below.

Voltage100 VAC or VDC Abs. Max.
Current0.250 Amp AC/DC Abs. Max.
Power5 Watts Max.
Contact Configuration N.O.
Housing MaterialPVDF, Black
Load Type5 feet, 24 wire

*For use with F-300 flowmeters which contain a RED float.

Instruction Manual (PDF) (PN 80000-575)


Flow Rate Sensor

Detects if water flow rate is at desired level. A built-in contact closure switch can remotely turn on/off a chemical pump and/or other external devices when flow rate is within desired range. Additionally, this can be used as an alarm signal if flow rate is not within flow range target, potentially indicating a clogged filter, malfunctioning equipment, closed valve, etc.

  • With flow rate sensor installed at targeted flow rate, the sensor can detect if your flow is within desired range. The alarm hysteresis window is approx. 10GPM (varies).
    1. ie. Target water flow rate is 65 GPM, alarm is placed so that 65 GPM is positioned in middle of indicator window. Sensor will trigger alarm at flow from 60 to 70 GPM

    Flow Switch

    Detects if water is flowing through the pipe. If float leaves “Alarm trigger zone,” a built-in contact closure switch can remotely turn on/off a chemical pump and/or other external devices.

  • With sensor installed at the base of the scale, the switch can detect a flow / no flow situation.