FHG1000-Series

Supported Applications

The Omega FHG-1000 Series Screw Gear Flow Meter is designed for measuring the flow rate of high viscosity liquids. Based on the screw pump principle, these positive displacement meters utilize a pair of rotors to form closed measuring chambers, enabling pulsation-free measurement with low pressure loss. The series supports fluids within a viscosity range of 1 to 1,000,000 cSt.

Media compatibility is defined by the following constraints:

• Liquids that are not abrasive
• Fluids free from contaminants or solid particles requiring filtration
• Substances without fillers or additives capable of blocking the measuring element

The device is CE certified and compliant with EMC Directives (EN 61000-6). Omega holds ISO 9001 certification for its manufacturing facilities in Stamford, CT and Manchester, UK.

Operating Conditions & Performance

The FHG-1000 Series operates within a fluid temperature range of -30 to 120°C (-22 to 248°F). The sensor module features an IP65 protection class and includes reverse polarity protection. Power supply requirements are 10 to 28 Vdc, with a current consumption of 65 mA at 24 Vdc (unloaded).

Performance specifications include:

• Accuracy: ±0.5% of measured value with viscosity > 21 cSt
• Repeatability: ±0.05% under the same operating conditions
• Response Time (Delay): < 8 μs maximum between scanning and measured value
• Output Frequency Range: 0 to 100 kHz, adjustable
• Resolution: Selectable in steps from factor 1 to 128

The series offers four distinct flow ranges depending on the model size: 0.5 to 120 LPM (0.13 to 32 GPM), 1 to 500 LPM (0.26 to 132 GPM), 4 to 1000 LPM (1 to 264 GPM), and 10 to 3000 LPM (2.6 to 793 GPM).

Pressure Ratings by Connection Size

• SAE Metric ¾" and 1¼": 6000 psi
• SAE Metric 2": 6000 psi
• SAE Metric 4": 490 psi

Configuration Options

The FHG-1000 Series is configurable across housing materials, bearing types, and flange connection sizes. The non-contact signal pick-up system uses two GMR bridges (sin/cos) in a cartridge design to detect rotor rotation, converting movement into digital pulses processed by an integrated preamplifier.

Housing Materials

• Cast Iron: EN-GJS-400-15 (EN 1563) / 16 Mn Cr 5
• Stainless Steel: Stainless steel 1.4305/1.4112; other materials available upon request

Bearing Types and Seals

• Bearings: Anti-friction (ball) or SSIC/wolfram carbide friction bearing, dependent on fluid compatibility.
• Seals: Standard FPM; optional PTFE, NBR, or EPDM

Electrical Outputs and Connections

The series provides an M12 5-pin shielded connector. Output signals include quadrature signals (A, B with 90° phase shift), directional output, and error output.

• Directional Output: Positive high (24V), negative low (0.8 to 1V)
• Error Output: Active high (24V), inactive low (0.8 to 1V)
• Signal Voltage Output: Vss = 9 to 27 Vdc
• Maximum Signal Current: Iout = 300 mA at 24 Vdc per channel

A recommended accessory, the FHG-CABLE, is a 5 m (16.4') long M12 5-pin shielded cable with meter plug to stripped leads.

Key Product Differences

The series distinguishes models by size code, housing material, bearing type, and flange connection pressure rating. Model numbers follow the format FHG----.

• Size 1 (FHG-1xxx): Flow range 0.5 to 120 LPM; available with SAE Metric ¾" flanges.
• Size 4 (FHG-xxx4): Flow range 1 to 500 LPM; available with SAE Metric 1¼" flanges.
• Size 5 (FHG-xxx5): Flow range 4 to 1000 LPM; available with SAE Metric 2" flanges.
• Size 7 (FHG-xxx7): Flow range 10 to 3000 LPM; available with SAE Metric 4" flanges at a reduced pressure rating of 490 psi.

Housing material codes differentiate between cast iron and stainless steel models, while bearing type options include ball bearings or hard metal (friction) bearings. All variants support installation in any position.