Combination pH/ORP Sensor - Emerson

1 FEATURES AND APPLICATIONSThe Rosemount Analytical Model 399 Sensor measuresthe pH or the Oxidation Reduction Potential (ORP) ofaqueous solutions in pipelines, open tanks, or is suitable for virtually all applications where a lowcost, disposable Sensor is required. The combinationelectrode features a ceramic junction constructed inan annular design around the pH/ORP sensitivemembrane. The double junction reference cell con-figuration is resistant to process solutions containingammonia, chlorine, cyanides, sulfides, or other poi-soning glass electrode is housed in a molded Tefzel 1body and sealed with Viton 1O-rings to guard againstprocess leakage.

2 The cable end of the Sensor is alsosealed, eliminating cable shorts caused by exposureto moisture. This construction makes for a highlychemical resistant disposable Sensor and does notrequire electrolyte replenishment. The custom glass electrode is available with either astandard hemi bulb or an optional flat bulb to bestmeet your application needs. Flat glass is advanta-geous in abrasive or coating applications that etch orbuild up on the glass respectively. In coating applica-tions, such as slurries, the flat surface allows theprocess flow to act as a scrubbing agent to reducecoating and maintenance whereas in abrasive appli-cations pitting from silicates and other similar materi-als is minimized by the flat surface to provide longerlife.

3 The hemi bulb is ideal for general purpose useand for those processes requiring greater accuracyover the entire pH rangeThe Rosemount Analytical pH/ORP Sensor offers anoptionalintegral preamplifier to convert the highimpedance pH or ORP mV signal into a stable, noise-free signal with transmission capability of up to threemiles. The Rosemount Analytical preamp method hasbecome the industrystandard for pH/ORP measure-ment is easily achieved through the wide varietyof mounting configurations. The Model 399 features1 in. (MNPT) front and rear facing connections forinsertion, submersion or flow through pH and PHYSICAL SPECIFICATIONSM aterials of Construction: Tefzel 1, glass, ceramic and Viton 1(also, Platinum for ORP Sensor )Process Connections: 1 in.

4 MNPTI nterconnecting Cable: 5 conductor, 10 or 32 ft cableundressed (integral preamp)10 ft coax cable (Code 02, 09)10 ft shielded coax cable (Code 04) 4 conductor, 20 or 100 ft cable undressed (Code 12, 13, 33)Measured Range: pH: 0-14 ORP: 1500 -+1500mVPercent Linearity over pH range:Temperature Compensation: Automatic 0 to 85 C (32 to 185 F) (Temperature compensation is not required for 399 ORP when used with Models 1060, 1023 or 1181 ORP)Maximum Pressure:790 kPa abs (100 psig) at 65 C(Refer to Graph A on page 4)Weight/Shipping Weight: kg (1 lb/2 lb)1 Tefzel and Viton are registered trademarks of DuPont 399 Combination pH/ORP SensorManual Instruction SheetPN 51-399 2009 Hemi BulbFlat Bulb1-2 pH94%93%2-12 pH99%98%12-13 pH97%95% Sensor is shipped in a con-tainer with special cushioning material.

5 Before openingthe container, it should be inspected for any damage. Ifany damage is detected, the carrier should be notifiedbefore proceeding further. Carefully remove the sensorfrom the container and packing material. Inspect thesensor for any visible damage. If no damage is found,carefully remove the rubber boot which protects theglass electrode and keeps the liquid junction wetted. NOTEIf the Sensor is to be stored, the rubber bootshould be filled with pH buffer solution andreplaced on Sensor tip until ready to Sensor down thesensor to remove any air bubbles that may be presentat the tip of the pH glass electrode must be wetted at all times(in storage and in line)

6 To maximize CALIBRATION USING A STANDARDBUFFER Make a temporary electrical connection betweenthe Sensor and Consult the appropriate pH or ORP analyzer/transmitter instruction manual for the specific cali-bration and standardization After successful completion of the calibration andstandardization procedure, install the Model 399sensors in the process (see Figures 2 through 9). Sensor has beendesigned to be located in industrial process environ-ments. Temperature and pressure limitations must notbe exceeded at any time (see Graph A).

7 Flow Through Installations. The Model 399 Sensor has a 1 in. MNPT process connection at thefront of the Sensor for mounting directly into a 1-1/2 See Figure 2 for installation configurations. It isrecommended that shut-off valves be provided for sen-sor removal and Insertion Installations. The Model 399 Sensor hasforward and rear facing 1 in. MNPT process connec-tions for pipeline installations utilizing flange connec-tions. The Model 399 is also suitable for side-of-tankinstallation. The Model 399 must be mounted 15 - 30 above horizontal (see Figure 3).

8 Submersion Mounting. The Model 399 Sensorhas a 1 in. MNPT process connection at the back of thesensor (see Figures 4 and 5). Utilizing a standard 1 , the Sensor may be mounted to a 1 in. SCH 80 CPVC or PVDF standpipe. Tapered pipe threads inplastic tend to loosen after installation. It is thereforerecommended that the tightness of the connection bechecked frequently to assure that no loosening hasoccurred. To prevent rain water or condensation fromrunning into the Sensor , a weatherproof junction box isrecommended (Rosemount Analytical PN 22719-02).

9 The Sensor cable must be run through a protectiveconduit for isolation from electrical interference orphysical abuse from the process. The Sensor shouldbe installed within 80 of vertical, with the electrodefacing down. The Sensor s cable should not be run withpower or control PIPE WRENCHES MUST NOT BEUSED TO TIGHTEN THE Sensor INTO AFLANGE OR OTHER TYPE OF Model 399 has an optional built-inpreamplifier and comes standard with a shielded cableor coax cable. The cable should be handled carefullyand kept dry and free of corrosive chemicals at alltimes.

10 Extreme care should be used to prevent it frombeing twisted, damaged or scraped by rough, sharpedges or surfaces. The cable is supplied refer to Figures 10 through 28 or the applicableanalyzer/transmitter instruction manual for the Sensor has been installedand the process solution is in contact with the Sensor ,the transmitter may need to be recalibrated. A grabsample method is recommend. Please refer to youranalyzer/ transmitter s instruction manual for Model 399pH has an automatic temperature com-pensator.