SFC Measuring and Control System

Summary

Product identification

The SFC instrumentation system is a modular device for the continuous measurement and control of water quality parameters. It can function as an analyzer, a set-point or flow proportional controller, or a combined analyzer/controller.

Key Benefits

• Utilizes Wallace & Tiernan® potentiostatic sensors from DEPOLOX® 5, Micro/2000®, and Deox/2000® modules.
• Offers four selectable control modes.
• Features simple configuration and operation.
• Provides data connectivity via 4–20 mA output, optional Process Monitoring System (web technology), and optional Profibus® DP or Modbus® TCP fieldbus modules.

Typical Applications

• Potable water treatment
• Wastewater treatment
• Cooling water circuits
• Industrial and process water treatment
• Swimming pools

Features

The SFC analyzer/controller is a modular system comprising an electronic module (wall or panel-mounted), a flow cell module, and a plug-and-play sensor measuring module. It supports over 10 different measurement types.

Control Options

The SFC system offers flow proportional control and compound loop control. Control modes are software-selectable. The unit can control actuators such as V10k™ gas feed systems, dosing pumps, or frequency converters.

• Flow proportional control: Proportionally controls chemical feed based on a measurement signal (e.g., external flow rate) and a configurable dosing factor.
• Compound loop control with external measurement: Utilizes an external measurement (mA input) for control.
• Single feedback closed-loop control: Can be used with external setpoint selection.

Sensor Selection

The SFC system supports a variety of measurement parameters:

• Free chlorine
• Total chlorine
• Chlorine dioxide
• Ozone
• Potassium permanganate
• pH value
• Redox (ORP)
• Fluoride
• Conductivity
• Temperature
• Standard sensors with a milliamp signal

Specific measurement modules mentioned include:

• DEPOLOX® 5: Potentiostatic bare electrode technology, fast-acting for disinfection control, with continuous hydromechanical sensor cleaning.
• Micro/2000®: Potentiostatic bare electrodes, can incorporate buffer chemicals, suitable for poor water quality without fouling, offers high accuracy for chlorine measurements down to one part per billion.
• Deox/2000®: Potentiostatic bare electrodes, used for dechlorination chemistry measurements.
• Membrane measurement module: Uses membrane-covered electrodes with the VariaSens flow cell, less affected by water chemistry variations.
• Strantrol® flowcell with HRR® sensor: Designed for highest accuracy in ORP measurement for industrial applications.

Technical Data

SFC Electronic Module

• Display: Graphical display, 128 x 64 pixels resolution, white background illumination.
• Measurement Inputs:
  • 1 x measured value input (electrically isolated up to 50 V) for sensor measuring module plug-in cards:
    • 3-electrode cell for chlorine, ozone, chlorine dioxide, potassium permanganate (DEPOLOX® 5, Micro/2000®, Deox/2000® modules)
    • Membrane sensors for total chlorine (TC3), free chlorine (FC2), chlorine dioxide (CD7), ozone (OZ7)
    • pH value
    • Redox voltage (ORP) with HRR® sensor or standard sensor
    • Fluoride
    • Conductivity
    • mA/V input
  • 1 x mA input for flow rate (0 – 20 mA / 4 – 20 mA)
  • 1 x mA input for external setpoint or dosing factor (0 – 20 mA / 4 – 20 mA) (not applicable to SFC SC)
  • 1 x temperature input PT 1000 (0 – 50 °C / 32 – 122 °F) with sensor error display (not applicable to SFC SC/SFC PC)
  • 1 x feedback input for servo motor position feedback (1 kΩ, 5 kΩ, mA, V)
• Digital Inputs: 2 x for voltage-free contact (< 100 Ω) for controller stop, flow control.
• Relay Outputs: 4 x freely selectable two-way switches for process monitoring; SFC SC: 2 alarm/control contacts.
• mA Outputs:
  • 1 x mA output for measurement or control output (freely configurable).
  • Output 0/4 – 20 mA.
  • Accuracy < 0.5 % FS.
  • Load protected ≤ 500 Ω.
  • Temperature drift max. 0.2 % / 10 °C.
  • Electrically isolated up to 50 V to ground.
• Interfaces:
  • 1 x RS 485 for connection to Process Monitoring System and OPC-Server (electrically isolated up to 50 V to ground).
  • 1 x CAN interface (not applicable to SFC SC and SFC PC).
  • 1 x slot for fieldbus connection: Profibus® DP, Modbus® TCP (not applicable to SFC SC).
  • 1 x RS 232 for firmware updates (not electrically isolated).
• Memory Card: 1 x SD memory card slot (not applicable to SFC SC).
• Power Supply:
  • 100 – 240 V AC ± 10 %, 50 – 60 Hz, 30 VA.
  • 24 V DC ± 20 %, 15 W.
• Enclosure: IP 66, designed to meet NEMA 4X.
• Testing and Marking: CE, EMC-EN 61326, IEC EN 61010, UL listed/CSA certified.
• Ambient Temperature: 0 – 50 °C (32 – 122 °F) (do not expose to direct sunlight).
• Storage Temperature: -20 to +70 °C (-12 to 158 °F).
• Dimensions (W x H x D): 185 x 265 x 145 mm (7.3 x 10.4 x 5.7 inches).
• Weight: approx. 2.5 kg (5.5 lbs).

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Disclaimer This extraction may miss figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror