Technical Parameters
Parameter Specification
Model Fisher 2500
Type Electronic Torque Tube Level Transmitter
Measurement Principle Buoyancy (Torque Tube)
Output Signal 4-20 mA DC, two-wire
Power Supply 12 to 45 V DC (standard for two-wire loop)
Mounting Top-mounted (suspended from the top of the vessel).
Displacer Lengths Available in a wide range of standard lengths to match the required level measurement span.
Process Connections Typically 2-inch or 3-inch NPT or 150# / 300# Flange.
Body Materials Carbon Steel, Stainless Steel
Displacer & Torque Tube Stainless Steel (standard), Monel, and other alloys available for corrosive services.
Temperature Limits Standard: -20°F to 450°F (-29°C to 232°C).
High-Temp versions available up to 850°F (454°C).
Pressure Rating Up to 3000 psig (207 bar) depending on model and torque tube rating.
Accuracy ±0.5% of span (typical)
Technical Parameters
Parameter Specification
Model Fisher 655 (Direct-Acting) Fisher 655R (Reverse-Acting)
Type Spring-Return Diaphragm Actuator
Action Air-to-Open / Spring-to-Close Air-to-Close / Spring-to-Open
Standard Signal Range 3 to 15 psig (0.2 to 1.0 bar)
Supply Pressure Range Up to 45 psig (3.1 bar) for the 3-15 psig range.
Spring Ranges Multiple springs available for different thrust outputs and fail-safe actions.
Effective Area Varies by size. Example (Size 70): 199 in² (1284 cm²)
Stem Thrust Varies by size and air pressure. Example (Size 70 at 15 psig): ~2985 lb (13280 N)
Stroke Lengths Available in various standard strokes, e.g., 0.5 to 4.0 inches (12.7 to 101.6 mm).
Temperature Limits -20°F to 150°F (-29°C to 66°C) with standard Buna-N diaphragm.
Diaphragm Material Buna-N with nylon cloth (standard)
Technical Parameters
Parameter Specification
Model Fisher™ 846
Type Two-Wire Electro-Pneumatic Transducer (I/P)
Input Signal 4-20 mA DC (Two-wire)
Output Signal 3-15 psig (0.2-1.0 bar); other ranges available.
Power Supply 24 V DC nominal (Typically operates on 12-30 V DC loop power)
Supply Air Pressure 20 to 60 psig (1.4 to 4.1 bar), clean and dry.
Air Consumption (No Load) Typically 0.25 SCFM (0.42 m³/hr)
Accuracy ±0.5% of span
Linearity & Hysteresis ±0.25% of span
Ambient Temperature Range -40°F to 180°F (-40°C to 82°C)
Enclosure Rating NEMA 4X (IP66)
Mounting Panel mount, DIN rail, or direct to actuator.
Technical Parameters
Parameter Specification
Model Fisher 2625
Type Constant Pressure, Pneumatic, Pressure-Reducing Regulator
Function Non-Relieving or Relieving (standard)
Connections (NPT) 1/4 in., 3/8 in., 1/2 in.
Body Materials Cast Iron (Standard), Ductile Iron, Stainless Steel
Internal Materials Buna-N, Stainless Steel, Brass
Maximum Inlet Pressure 400 psig (27.6 bar)
Outlet Pressure Range Spring Ranges available, e.g., 3-15 psig (0.2-1.0 bar), 3-27 psig (0.2-1.9 bar), 6-30 psig (0.4-2.1 bar), 10-60 psig (0.7-4.1 bar), etc.
Temperature Limits -20°F to 180°F (-29°C to 82°C) with standard Buna-N elastomers.
Flow Capacity (Cv) Approximately 1.8 (for a 1/2" NPT size). (Note: Cv varies slightly by size and configuration).
Leakage Bubble-tight shut-off (ANSI Class IV) for the main regulator. Minimal internal leakage to vent in relieving mode.
Mounting Panel mount (bracket required) or in-line.
Standards Complies with CE, PED, and other international standards depending on specific model and materials.
Technical Parameters
Parameter Specification
Model Fisher 656 (Non-Relieving), 656R (Relieving)
Type High-Pressure, Piston-Actuated, Pressure-Reducing Regulator
Function Non-Relieving (656) or Relieving (656R)
Connections (NPT) 1/4 in., 3/8 in., 1/2 in.
Body Materials Forged Carbon Steel (Standard), Stainless Steel
Internal Parts Stainless Steel, Buna-N (standard)
Maximum Inlet Pressure 6000 psig (414 bar)
Outlet Pressure Range Spring Ranges available, e.g., 5-50 psig (0.3-3.4 bar), 20-100 psig (1.4-6.9 bar), 50-250 psig (3.4-17.2 bar), and many other high-range springs.
Temperature Limits -40°F to 200°F (-40°C to 93°C) with standard Buna-N elastomers.
Flow Capacity (Cv) Approximately 1.8 (for a 1/2" NPT size). (Note: The 656 is designed for high ΔP, giving it a very high flow capability despite a Cv similar to smaller regulators).
Leakage ANSI Class IV shut-off (bubble-tight).
Mounting Panel mount (bracket required) or in-line.
Technical Parameters
Parameter Specification
Model Fisher A31A
Type Double-Acting, Scotch Yoke Pneumatic Actuator
Action Double-Acting (Air-to-Open / Air-to-Close)
Standard Travel 90° quarter-turn. (A 92° travel version is available for specific applications).
Body Material Aluminum with epoxy powder coat
Piston Seal Material Buna-N (Standard)
Operating Temperature Range -4°F to 180°F (-20°C to 82°C) with standard Buna-N seals.
Supply Pressure Range 40 to 120 psig (2.8 to 8.3 bar)
Torque Output Varies by size and supply pressure. Example (at 80 psig):
- Size 6: ~ 115 lb-in (13 Nm)
- Size 12: ~ 480 lb-in (54 Nm)
- Size 20: ~ 1325 lb-in (150 Nm)
Sizes (Frame Size) 6, 12, 20, 35, 60, 100, 160 (The number corresponds to the piston diameter in millimeters).
Technical Parameters
Parameter Specification
Model Fisher 1077
Type Balanced, Flanged Globe Valve
Trim Type Balanced Trim
Flow Characteristic Equal Percentage or Linear (depending on plug selection)
End Connections ANSI Class 150, 300, or 600 Flanged (RF or RTJ)
Body Materials Carbon Steel (WCB), Stainless Steel (CF8, CF8M), Alloy 20, etc.
Trim Materials Stainless Steel (Standard), Hardened alloys for severe service.
Temperature Range -20°F to 1000°F (-29°C to 538°C) depending on body/trim materials and seat gasketing.
Pressure Rating ANSI Class 150: 275 psig (19 bar)
ANSI Class 300: 720 psig (49.6 bar)
ANSI Class 600: 1440 psig (99.3 bar)
Leakage Class ANSI Class IV (Standard)
ANSI Class VI (Soft Seat) options available.
Sizes (Pipe Size) 1" to 8" (DN 25 to DN 200)
Technical Parameters
Parameter Specification
Model Fisher 3661 (Various suffixes denote specific types, e.g., 3661L for large displacer)
Type Pneumatic Displacer Level Controller
Measurement Principle Buoyancy (Torque Tube)
Output Signal 3 to 15 psig (0.2 to 1.0 bar) pneumatic, proportional to level
Supply Air Pressure 20 psig (1.4 bar) minimum, typically 20-35 psig (1.4-2.4 bar) is supplied.
Air Consumption Very low at steady state; typically < 0.1 SCFM (0.17 m³/hr).
Mounting Top-mounted (suspended from the top of the vessel).
Displacer Length Available in various standard lengths to match the required level measurement span.
Process Connections Typically 2-inch NPT or 150# / 300# Flange.
Body Materials Cast Steel, Stainless Steel, Alloy Steel
Displacer & Torque Tube Stainless Steel (standard), other alloys available for corrosive services.
Temperature Limits Standard: -20°F to 450°F (-29°C to 232°C).
High-Temp versions available up to 850°F (454°C).
Pressure Rating Up to 3000 psig (207 bar) depending on model and torque tube rating.