Series-SFI-800

Supported Applications

The Dwyer Series SFI-800 Rugged Flow Indicator & Transmitter provides sight flow indication with optional Hall Effect output packages for remote monitoring of liquid flow. The series is designed for applications including cooling and lubrication circuits, HVAC systems, aggressive chemical metering, and batching systems. Specific configurations support the monitoring of chilled or hot water flow and water flow in chillers.

The SFI-800 body models utilize FDA/NSF-ratable wetted materials suitable for potable water applications, de-ionized water, many acids, bases, and salts. The Series SFI-100T variant is specified for monitoring chilled or hot water flow in chiller systems.

Operating Conditions & Performance

The series accommodates fluid temperatures ranging from -20 to 212°F (-29 to 100°C) for SFI-800 models and electrical sensor options, while SFI-801 bodies are rated for -20 to 130°F (-29 to 55°C). Pressure limits are specified as 150 psi (10.34 bar) for the SFI-800 series and 125 psi (8.62 bar) for the SFI-801 and SFI-100T models.

Flow measurement ranges vary by model size and configuration:

• SFI-800/SFI-801 1/2" models: 2 to 20 GPM (7.6 to 75.5 LPM)
• SFI-800/SFI-801 3/4" models: 3 to 35 GPM (11.4 to 132.5 LPM)
• Low Flow (-LF) 1/2" models: 0.5 to 6.5 GPM (1.9 to 24.6 LPM)

The maximum fluid viscosity is rated at 200 SSU. Accuracy for the A-711, A-711T, and A-712 output options is ±5% of Full Scale (F.S.). The frequency output range for pulse signals is 0 to 100 Hz.

Configuration Options

The series offers configurable body materials, process connections, and electrical output packages. All three sensor options can be installed or replaced in the field without tools and without removing the body from the process line.

• Housing Materials: SFI-800 bodies are Polysulfone; SFI-801 bodies are UV Stabilized Polycarbonate for outdoor use. The Series SFI-100T features a brass body with a tempered glass window.
• Wetted Components: Rotor pins and thrust washers utilize 316 SS and 300 Series SS respectively. O-rings are Fluoroelastomer (NSF Grade) for SFI-800 or Buna-N for SFI-801/SFI-100T.
• Process Connections: Female NPT connections available in 1/2" and 3/4" sizes. The Series SFI-100T requires horizontal mounting orientation.

Electrical Output Options

The series supports three distinct output configurations, each with specific power requirements:

• A-711 / A-711T (Pulsed Output): Provides two pulse voltage signals proportional to flow rate. White lead outputs 5 VDC; Green lead outputs 8 - 28 VDC equal to supply voltage. Power requirement is 8 - 28 VDC.
• A-712 (Linear Output): Delivers a linear 1 to 10 VDC signal proportional to flow rate via the White lead. Requires 15 - 28 VDC power supply.
• A-713 (Flow Switch): Features two programmable open collector switch outputs with set point button and red LED indication. White lead is Normally Open; Green lead is Normally Closed. Both are rated for 100 mA max, 28 VDC max. Power requirement is 8 - 28 VDC.

Key Product Differences

The Series SFI-800 and SFI-801 differ primarily in housing material composition and environmental suitability. The SFI-800 Polysulfone body is adversely affected by ultraviolet light and should be installed indoors, whereas the SFI-801 UV Stabilized Polycarbonate body is rated for indoor or outdoor use.

The Series SFI-100T represents a distinct variation with a brass body and tempered glass window, differing from the clear plastic construction of the SFI-800/801 series. While the SFI-800 wetted materials are FDA/NSF ratable for potable water applications, the SFI-801 is not FDA-approved.

Model numbering follows a structure combining body model and option suffix (e.g., SFI-800-1/2-A711). Sensor packages A-711, A-712, and A-713 are available separately or attached to the flow indicator body. The Series SFI-100T is offered with an integrated A-711T sensor package.