Georg Fischer 274x Specifications

Signet 2744-2747 Di erential DryLoc®
pH/ORP Electrodes

High Performance

Protected

Bulb

The Signet 2744-2747 Differential pH and ORP
electrodes are high performance sensors built with the
DryLoc® connector, a Ryton® body, and PTFE reference
junction to handle the most extreme and harshest of
chemical applications.

These differential electrodes use a field-proven
3-electrode differential technique: the pH and reference
electrodes are measured against a ground electrode,
ensuring a steady and stable signal.

Flat

Glass

Features

• Di erential design for stable measurements in
the most aggressive applications

• Long service life even in severe or di cult
chemical applications

• Memory chip enabled for access to a wide range
of unique features when connected to the Signet
2751 pH/ORP Smart Sensor Electronics

• High performance glass that can withstand
high pH caustic media as well as elevated
temperature applications

• Ryton (PPS) body for broad range of chemical
compatibility

• Watertight DryLoc® connector with foul-proof
gold plated contacts*

• Porous PTFE reference junction resists fouling
and chemical attack

• Rebuildable reference electrode

• Solution ground

• Temperature sensor (pH)

A key feature is the reference electrode, which is housed
in a glass half-cell embedded in the reference chamber
and is protected from compounds that may contain
sulfides (S2-) and metals. To ensure long service life,
the reference features a refillable electrolyte chamber
and a replaceable equitransferant salt bridge, both
easily serviced in the field. The patented porous PTFE
reference junction resists fouling, clogging and chemical
attack.

Other elements of the design are the solution ground,
the pH/ORP electrodes, and the temperature element.
The solution ground eliminates noisy measurements
by draining electrical current away from the reference
electrode. The pH/ORP electrodes are designed with a
flat or bulb surface, and a temperature device positioned
at the tip of the measurement surface for a quick
temperature response. Various temperature devices
offered include 3 KΩ or Pt1000 RTD.

The electrodes are used with the Signet 2751 Smart
Sensor Electronics, which provide a blind 4 to 20 mA
output or use the digital (S3L) output to connect the
Signet 8900, 9900 or 9950 instruments, and the
0486 Profibus Concentrator. The electrodes can also be
used with the 2760 Preamplifier to connect to ProPoint®
and ProcessPro® series of pH/ORP instrumentation.

• Easy sensor replacement using DryLoc
electrode connector

• Quick temperature response

• Compatible with all Signet instruments

Applications

• Plating Baths

• Surface Finishing

• Plant E uent

• Water and Wastewater Treatment

• Scrubbers

• Textile Dye Process

• Harsh Chemical Applications

• Heavy Metal Removal and Recovery

• Toxic Destruction

• Coagulation and Flocculation

See Technical Reference section for assistance in choosing
the correct sensor.

*U.S. Patent No.: 6,666,701

Specifi cations

General

Compatibility Signet 2751 and 2760

Operating Range 2744/2746 0 to 14 pH

2745/2747 ±1500 mV (ORP)

Process Connection 1 in., for use in reducing tees up to 4 in.

Wetted Materials

Body Ryton®

Reference Junctions PTFE

Sensing Surface pH Glass membrane

ORP Platinum

O-rings EPDM

Solution Ground Carbon graphite

Max. Temperature/Pressure Rating

Operating Temperature Range 10 °C to 100 °C 50 °F to 212 °F

Operating Pressure Range 0 to 6.9 bar (0 to 100 psi) @ 10 °C to 65 °C (50 °F to 149 °F)

Linearity Derated 6.9 to 4.0 bar (100 to 58 psi) @ 65 °C to 100 °C (149 °F to 212 °F)

Recommended Storage Temperature

0 °C to 50 °C 32 °F to 122 °F

The electrode glass will shatter if shipped or stored at temperatures below 0 °C (32 °F).

The performance life of the electrode will shorten if stored at temperatures above 50 °C (122 °F).

Mounting

In-line/Vertical Mounting Use sensor 1 in. threads. Sensor must be mounted at least 15 degrees above

the horizontal axis.

Submersible Mounting Use threads on Model 2751 or 2760; requires ¾ in. NPT or ISO 7/1-R 3/4 male

threaded extension.

Reference

Electrolyte Bu ered equi-transferant salt solution gel

Element pH half-cell

Temperature Sensor pH 3 KΩ, Pt1000 RTD

ORP 10K ID Resistor

Shipping Weight

0.25 kg 0.55 lb

Standards & Approvals

Manufactured under ISO 9001, 14001 and OHSAS 18001 for Quality

www.gfsignet.com