Leici PHGF-46 Inline pH/ORP Transmitter Series

Overview

The Leici PHGF-46 Inline pH/ORP Transmitter Series is an industrial-grade process analytical instrument engineered for continuous, real-time monitoring of hydrogen ion activity (pH) and oxidation-reduction potential (ORP) in flowing aqueous streams. Designed around a two-wire 4–20 mA current loop output with HART® protocol support (optional), the PHGF-46 operates on the principle of potentiometric measurement—detecting the thermodynamic voltage difference between a reference electrode (Ag/AgCl or calomel) and a sensing electrode (glass membrane for pH, noble metal for ORP) immersed in the process stream via a dedicated flow-through cell. Its modular architecture enables seamless integration into PLC-based control systems, DCS networks, or SCADA platforms across water treatment, chemical synthesis, metallurgical leaching, aquaculture recirculation systems, and environmental compliance monitoring applications. The transmitter complies with IEC 61000-6-2 (immunity) and IEC 61000-6-4 (emission) standards and is rated IP65 for panel-mount or wall-mount installation in non-hazardous industrial environments.

Key Features

• Modular flow cell configuration system supporting eight standardized variants (P2N1 through S1Y1), enabling selection of optimal geometry (straight inline FT-01, T-fitting FS-02, or angled insertion FX-03/FX-04) and preamplifier integration (Y = built-in signal conditioning, N = remote amplifier required).
• Chemically resistant wetted materials: configurable housing options include PVC (A=P), CPVC (A=C), SS304 (A=T), and fully passivated SS316 (A=S) for aggressive media such as chlorinated brines, acidic mine drainage, or caustic soda solutions.
• Wide operational temperature range: standard calibration and measurement stability maintained from 0 °C to 55 °C; optional high-temperature configurations extend validated performance to 100 °C when paired with compatible electrodes (e.g., T-819-A Pt100 temperature sensor for automatic temperature compensation).
• Robust pressure rating of 0.6 MPa (6 bar) at 20 °C, suitable for pressurized pipelines in municipal water distribution, boiler feedwater circuits, and electroplating rinse lines.
• Flexible mechanical interface: inlet and outlet ports accept standard NPT/BSP threaded connections (1″, 1/2″, 3/4″) or direct-tube insertion (Φ6×1 mm inlet, Φ10×1 mm outlet), minimizing dead volume and ensuring representative sampling without bypass loops.
• Compliance-ready design: supports GLP/GMP-aligned data integrity workflows when integrated with Leici’s certified software suite; meets requirements for traceable calibration logging per ISO/IEC 17025 and ASTM D1293 (pH of water) and ASTM D3222 (ORP of aqueous solutions).

Sample Compatibility & Compliance

The PHGF-46 is optimized for clean-to-moderately fouling aqueous matrices—including potable water, wastewater effluent, process cooling water, desalination brine, pharmaceutical rinse water, and aquaculture circulation systems. It is not recommended for highly viscous, abrasive, or gas-saturated streams without upstream filtration or degassing. All electrode combinations (FG-991A, FG-990/T-819-A) are CE-marked and compliant with RoHS 2011/65/EU. The transmitter’s analog output meets EN 60770-1 for industrial transmitters, and its electrical safety conforms to IEC 61010-1 (Pollution Degree 2, Overvoltage Category II). For regulated industries, optional firmware enables audit-trail-enabled calibration events, user access levels, and electronic signature support aligned with FDA 21 CFR Part 11 requirements when deployed with validated host software.

Software & Data Management

Leici provides the Leici LabLink™ PC Utility (Windows-compatible) for configuration, diagnostics, and calibration management. The utility supports multi-point pH buffer recognition (NIST, DIN, USA, TECH), slope/mV offset validation, ORP zero-point verification using quinhydrone or Zobell’s solution, and temperature coefficient adjustment. All calibration parameters, timestamps, operator IDs, and raw mV readings are exportable in CSV format for LIMS integration. When connected to Leici’s cloud-enabled iMonitor™ platform (optional subscription), the PHGF-46 supports remote parameter adjustment, predictive maintenance alerts based on drift rate analysis, and automated report generation compliant with ISO 5725 (accuracy/trueness) and ISO 80000-9 (quantities and units).

Applications

• Municipal and industrial wastewater treatment: real-time pH control in neutralization tanks, ORP monitoring in disinfection basins (chlorine, ozone, UV-peroxide systems).
• Power generation: boiler feedwater pH optimization, condensate polishing loop surveillance, and corrosion inhibitor dosing feedback.
• Chemical manufacturing: batch reactor endpoint detection, scrubber liquor monitoring, and catalyst regeneration process control.
• Aquaculture and hydroponics: closed-loop pH stabilization in recirculating aquaculture systems (RAS) and nutrient film technique (NFT) grow channels.
• Environmental monitoring stations: long-term deployment in river intake points, groundwater wells, and stormwater outfalls under EPA Method 150.1 and ISO 10523 protocols.

FAQ

What is the maximum allowable process temperature when using the standard FG-991A electrode?
The FG-991A electrode is rated for continuous operation up to 55 °C. For higher temperatures, the T-819-A temperature-compensated ORP/pH combination electrode must be specified with FX-04 flow cell configuration.
Can the PHGF-46 transmit both pH and ORP simultaneously over a single 4–20 mA loop?
No—it outputs either pH or ORP as a primary variable; secondary variables (e.g., temperature) require HART digital communication or a separate analog channel.
Is third-party calibration certificate available for ISO/IEC 17025 accreditation?
Yes—Leici offers factory-issued calibration reports traceable to NIM (National Institute of Metrology, China) standards, with optional UKAS-accredited certification via authorized partners.
How often should the flow cell be cleaned in hard-water applications?
Recommended cleaning interval is every 7–14 days using 0.1 M HCl or citric acid solution; automated CIP cycles can be triggered via relay output when paired with Leici’s optional cleaning controller module.
Does the transmitter support Modbus RTU or TCP/IP communication?
Standard model supports HART 7; Modbus RTU (RS-485) and Ethernet/IP interfaces are available as factory-configured options (model suffix “-M” or “-E”).