תיאור
– Wastewater Treatment Plant Digester Systems
– Biogas Production and Recovery
– Anaerobic Digester Processes
– On-Farm Systems
– Fermentation Systems
– Landfill Gas Recovery Systems
– Co-Gen Power Systems
– Coal Mine and Coal Bed Methane Recovery
The ST51 Series Flow Meter is an accurate, easy to install, no moving parts
solution for measuring and controlling biogases, digester gases, methane and
natural gas flow. ST51 utilizes FCI proven thermal dispersion technology to provide
direct mass flow measurement resulting in higher performance at a lower cost than
orifice plates, DP, Vortex shedding and other thermal devices.
Biogas and digester gas applications are challenged by wide flow variations and
dirty, wet gas. Flow variation is experienced as these processes move from low
production start-up phases to a consistent, sustainable process and by seasonal
temperature change, where cold temperatures slow gas production and higher
temperature accelerate gas production. While the primary composition of these
gases is methane and CO2 , residual H2S and wet vapor leave deposits and corrode
surfaces.
ST51 provides the solution to these challenges.
It features a wideturndown ratio, up to 100:1 and is highly sensitive to low flow measurement.
To measure correctly in fluctuating temperatures, flow meters must include
temperature compensation circuitry and it is standard in ST51. ST51 has no moving
parts to foul or clog and is easily pulled from the pipe for occasional cleaning.
ST51 installs in line sizes ranging from 2 1/2 inch to 24 inch [64 mm to 610 mm] with
1/2 inch or 3/4 inch NPT.
The ST51 uses precision, lithography structured platinum RTD sensors embedded
in FCI’s equal mass small diameter thermowells. Combined with microprocessor
electronics and precision calibration, the ST51 achieves excellent accuracy, fast
response and virtually maintenance free operation.
Features
– No Moving Parts, Non-Clogging
– Small, Compact Design
– Easy to Install
Dual 4-20 mA outputs per NAMUR NE43
500 Hz pulse output
HART (v7)
Modbus (485 RTU/ASCII)
Dual line LCD readout Optional
Process operating temperature To 250 °F [to 121 °C] To 350 °F [to 177 °C]
Remote distance Maximum 50 ′ [15 m] 100 ′ [30 m]
SIL compliance
Ex hazardous location approvals
Media Compatibility: Biogas, digester gas, methane, natural gas,
air, compressed air, nitrogen
Pipe/Line Size Compatibility: 2 1/2 ″ to 24 ″ [64 mm to 610 mm]
Flow Range: 0.3 SFPS to 400 SFPS [0,08 MPS to 122 MPS]
Accuracy: (at ≥ 0.75 SFPS [≥ 0,21 NMPS] 2)
Standard: ± 2% reading ± 0.5% full scale
Optional: ± 1% reading ± 0.5% full scale
Repeatability: ± 0.5% reading
Temperature Compensation
Standard: 40 °F to 100 °F [4 °C to 38 °C];
Optional: 0 °F to 350 °F [-18 °C to 177 °C]
Temperature Coefficient
With temperature compensation; valid from 10% to 100% of full scale calibration
Flow: Maximum ± 0.015% of reading / °F up to 350 °F [± 0.03% of reading / °C up to 177 °C]
Turndown Ratio: 3:1 to 100:1
Agency Approvals
FM, FMc: Class I, Division 1, Groups B, C, D; T4 Ta = +60°C; Type 4X, IP66
Class II/III, Division 1, Groups E, F, G; T4 Ta = +60°C; Type 4X, IP66
Model ST51 also includes: Nonincendive for Class I, Division 2,
Groups A, B, C, D; T4 Ta = +60°C; Type 4X, IP66
ATEX: Zone 1, Zone 21
II 2 G Ex db IIC T6…T1 Gb
II 2 D Ex tb IIIC T85°C… T300°C Db; IP66/IP67
Ta = -40°C to +65°C
IECEx: Ex db IIC T6…T1 Gb;
Ex tb IIIC T85°C…T300°C Db; IP66/IP67
Ta=-40°C to +65°C
Other: EAC (TRCU) Russia, NEPSI, CE Marking, CRN
SIL (ST51A): SIL 1 compliant; Safe Failure Fraction (SFF) 78.5% to 81.1%
Warranty: ST51 – 1 year; ST51 A – 2 years 1 For line sizes 2" [51 mm] or smaller, see FCI ST75 Series
2 Contact FCI for accuracy below 0.75 SFPS [0,21 NMPS]
Flow Element
Installation: Insertion, variable length with 1/2 ″ or 3/4 ″ MNPT compression fitting
Type: Thermal dispersion
Material of Construction: 316L stainless steel body with Hastelloy-C22 thermowell sensors,
316 stainless steel compression fitting with Teflon or stainless steel ferrule
Pressure (Maximum Operating without Damage)
Stainless steel ferrule: 500 psig [34 bar (g)]
Teflon ferrule: 150 psig [10 bar (g)]
Operating Temperature
Stainless steel ferrule
ST51: -0 °F to 250 °F [-18 °C to 121 °C]
ST51 A: -0 °F to 350 °F [-18 °C to 177 °C]
Teflon ferrule: -0 °F to 200 °F [-18 °C to 93 °C]
Process Connection
Compression Fittings: 1/2 ″ MNPT or 3/4 ″ MNPT with stainless steel or Teflon ferrule
Retractable
Packing Gland: Medium pressure 500 psig [34 bar(g)] with 1/2 ″ MNPT or
3/4 ″ MNPT, and either graphite or Teflon packing
Teflon packing is required if media is ozone, chlorine, or bromine
Insertion Length (Field Adjustable)
1 ″ to 6 ″ [25 mm to 152 mm]
1 ″ to 12 ″ [25 mm to 305 mm]
1 ″ to 18 ″ [25 mm to 457 mm]
Flow Transmitter
Enclosure
Rating: NEMA 4X, IP66/IP67
Material: Standard – aluminum, polyester powdered coated
Optional – 316 stainless steel
Conduit/Cable Port: Dual 1/2 ″ NPT or M20x1.5
Operating Temperature: 0 °F to 140 °F [-18 °C to 60 °C]
Input Power
DC: 18 Vdc to 36 Vdc (6 watts max.)
AC: 85 Vac to 265 Vac (12 watts max.; CE Marking approval from 100 Vac to 240 Vac)
Analog Output Signals: Dual 4-20 mA, user assignable to flow rate and/or temperature and a
0-500 Hz pulse output for total flow; output #1 has fault indication per NAMUR NE43 guidelines, user
selectable for high (> 21.0 mA) or low (< 3.6 mA)
Bus Communications (ST51A): HART or Modbus
HART: Version 7; FieldComm Group certifed; available over output #1; DD file included
Modbus: RS485 (in accordance with EIA/TIA-485 standard)
Modbus device type: Slave
Address range: 0-255
Supported function codes: 03,04
Supported baud rate: 9600,19200
Transmission mode: RTU and ASCII; standard MS (16 bit), standard LS (16 bit),
Daniel extensions (32 bit)
Response time
(delay between polls): 50 ms or greater
Functions
Readings: Flow rate, temperature, totalized flow (single precision),
flow engineering units, temperature engineering units
Other: Enable (activate) totalizer, reset totalizer, change K factor
Communication Port: RS-232C
Digital Display (Optional): Two-line x 16 character LCD; displays measured value and
engineering units; top line assigned to flow rate, second line user assignable to temperature
reading, as flow totalizer or alternating; display can be rotated in 90° increments for optimum
viewing orientation
Installation and Mounting: Integral with sensor element or remote mountable
up to 50 ′ [15 m] with Model ST51, and up to 100 ′ [30 m] with Model ST51A