Series-HFT

Supported Applications

The Dwyer Series HFT In-Line Flow Transmitter provides continuous monitoring of flow rate levels via a direct reading in-line flowmeter with electronics to provide proportional analog outputs. These transmitters are typically used to transmit a signal proportional to flow rate to a process control computer, a PLC, a recorder, or a panel-mount display. The series serves as the primary input device to record flow rates through hydraulic and pneumatic systems.

Operating Conditions & Performance

The Series HFT is designed for service with compatible gases or liquids up to 500 SSU viscosity. Process temperature limits are rated at 170°F (76°C). The transmitter delivers an accuracy of ±2% FS and repeatability of ±1% of full scale, with a response time of less than 100 msec.

Pressure ratings vary by body material: Aluminum bodies support up to 600 psig (41 bar), Brass bodies up to 3500 psig (240 bar), and 304 SS bodies up to 6000 psig (413 bar). The unit operates on a power supply of 12-35 VDC. For the 4-20 mA output, load resistance is defined as Rmax = 50(Vs - 12), and the input impedance of the receiving device must not be lower than 100 Ω to avoid non-linearities.

Configuration Options

The series offers a range of process connections, body materials, and output configurations tailored to specific flow ranges:

• Process Connections: Available in 1/4", 1/2", 3/4", 1", and 1-1/2" female NPT.
• Body Materials: Aluminum, brass, or 304 SS. Wetted materials include Buna-N or Fluoroelastomer seals; a PTFE coated Alnico magnet; and other internal parts in 304 SS.
• Housing & Enclosure: Rugged cast aluminum housing with NEMA 4X (IP65) enclosure rating. Overall dimensions are 7-1/8" height, 4-1/2" width, and 2-15/16" depth.
• Output Signals: The universal output circuit produces 4-20 mA, 0-5 VDC, or 1-5 VDC. A 1-5 VDC signal may be obtained from the 4-20 mA signal by placing a 249 Ω resistor in parallel with the receiver. Some configurations support a 0-2000 Hz square wave pulse output.
• Electrical Connection: Utilizes a 4-pin DIN connector.

The series supports various flow ranges depending on media and model, including water flows from .2 to 50 GPM (1 to 190 LPM) and air/gas flows up to 23 SCFM or higher. Shipping weight varies by connection size: 3 lb (1.4 kg) for 1/4" to 1/2" models, 4.5 lb (2.0 kg) for 3/4" to 1" models, and 12 lb (5.4 kg) for 1-1/2" models.

Key Product Differences

Variants within the Series HFT are distinguished by connection size, body material, and specific flow range capabilities:

• HFT-11xx Models (Aluminum): Feature 1/4" female NPT connections for air/gas ranges such as 2 to 12 SCFM or 4 to 23 SCFM.
• HFT-2xxx Models (Brass): Offered in 1/2", 3/4", 1", and 1-1/2" female NPT sizes for water ranges spanning .5 to 50 GPM. These models support higher pressure ratings up to 3500 psig.
• HFT-3xxx Models (304 SS): Available in 1/2" female NPT connections with low-flow water ranges such as .2 to 2 GPM or 1 to 10 GPM, supporting pressure ratings up to 6000 psig.

The series includes a green LED indicator for power status. Installation and cleaning instructions reference the Series HF In-Line Flow Monitor Bulletin F-55 for the basic flow monitor cartridge included with the unit.