Series-FS

Supported Applications

The Dwyer Series FS Flowmeter with Flow Limit Switch combines direct-reading, piston-type variable area flow measurement with a hermetically sealed solid-state switching module. This configuration provides instantaneous visual flow rate indication and an electronic signal to alert operators when incorrect flow rates are detected in compatible liquid services.

Operating Conditions & Performance

The series is designed for process temperatures up to 158°F (70°C) with a pressure limit of 325 psi (22.4 bar). Measurement accuracy is specified as ±5% full scale, and repeatability is 1.0%. The flow scales are calibrated at 1.0 specific gravity @ 70°F (21°C).

Configuration Options

The Series FS supports multiple measurement ranges depending on the model selection:

• FS10410: 0.5 to 4.0 GPM (1.9 to 15 LPM)
• FS11610: 1.0 to 16 GPM (5 to 60 LPM)
• FS12810: 4.0 to 28 GPM (20 to 100 LPM)
• FS20400: 0.5 to 4.0 GPM (1.9 to 15 LPM)
• FS20700: 1.0 to 7.0 GPM (4 to 26 LPM)

The series offers two process connection options:

• 1" male NPT Polysulfone
• 3/4" male NPT brass

Wetted materials include a polysulfone body, barium ferrite, and stainless steel spring and retaining rings. The unit features an adjustable set point from 0 to 100% FS with a latching relay output capable of switching loads consuming between 2.5 and 90 watts (or having 5000 Ω to 150 Ω impedance). For loads drawing less than 2.5 watts, a 0.47 μF loading capacitor is required.

Electrical Specifications

• Supply Voltage: 115 VAC, ±10%
• Current Consumption: 25 mA max
• Relay Load: 1 A @ 30 VDC; 0.5 A @ 125 VAC (resistive)
• Electrical Connection: Separate four conductor female connector with solder lugs labeled 1, 2, 3, and 4 (terminals 3 and 4 are not used)

Key Product Differences

The series distinguishes between models based on flow range and process connection material. Models FS10410, FS11610, and FS12810 utilize a 1" male NPT polysulfone body with an overall length of 5-1/4 [133.35] for the meter section; total assembly length including the switch module is 8-1/4 [209.55]. Models FS20400 and FS20700 utilize a 3/4" male NPT brass connection.

Weights vary by construction: the 1" male NPT polysulfone version weighs 0.55 lb (0.25 kg), while the 3/4" male NPT brass version weighs 0.90 lb (0.41 kg). The switch module dimensions are 1-7/8 [47.63] height and 1-47/64 [43.94] width.

Installation notes indicate the flowmeter can be mounted in any plane of orientation without affecting accuracy, as it does not require straight pipe lengths at the inlet or outlet to stabilize flow. The unit is CE approved.