Q45C4 - 4-Electrode Conductivity Monitor

4E Conductivity Monitor......Model Q45C4Model Q45C4Monitor FeaturesLoop-powered, AC, or Battery Versions: This line ofmicroprocessor based instrumentation allows for easyimplementation of loop-powered, line-powered, orbattery-powered capability within the same instrument. Itcan be rapidly converted between any of these versionswith no requirement for software change• Loop-powered (16-35 VDC) transmitter, 4-20 mAoutput• Line-powered (115/230 VAC) analyzer, dual relays,dual 4-20 mA outputs• Battery-powered (9 VDC) Monitor/Data Logger, dual0-2.5 VDC outputsPortable Data Logger: For even greater versatility, aportable unit powered by a standard 9V battery is alsoavailable. The dual 0-2.5 VDC outputs are assignable toconductivity and temperature. This instrument can besupplied with an internal data logger, making it ideal forshort-term monitoring at remote sites. The unit will run for10 days on a single battery and the data logger will storeup to 32,000 data points.Intuitive User Interface: Four-button programmingprovides intuitive navigation through the menu drivenuser interface. Dual Alarm Relays/Analog Outputs: AC operatedsystems provide two relays that are configurable for either“control mode” or “alarm mode” of operation. Diagnostic Messaging: Diagnostic messages provide aclear description of system condition, which eliminatesconfusing error codes that are difficult to decipher.Flexible Calibration: Two-point and sample calibrationoptions include stability monitors to check temperatureand main parameter stability before accepting data. While the theory of monitoring conductivity is simple, in practice itcan be very frustrating. While simple 2-electrode sensors areinexpensive and can provide accurate data, continuous monitoringof even relatively clean water can foul the electrodes and degradethe measurement. Maintaining accuracy is made more difficultwhen the amount of solids dissolved in the process varies over awide concentration range. In this case, a simple 2-electrode sensoris limited by its cell constant, which means it cannot measure theprocess accurately.ATI’s Q45C4 4-Electrode Conductivity Monitor is the answer formonitoring almost any water-based process. Drinking water,plating bath solutions, cooling water, process wash water, orvirtually any other aqueous system can be monitored accuratelyand reliably. The unique drive/control scheme used in the 4-electrode system allows a single sensor configuration to be used inconductivity ranges from 0-200 µS to as high as 0-2,000 mS (0-2 S).The “auto-ranging” feature enables the monitor to display theactual conductivity value during “overshoot” conditions. Forchemical mixing applications, a concentration display can beselected for a limited number of acids and bases. If your applicationinvolves very low conductivity/resistivity measurement, ATI canprovide the Q45C2 System that is used in process waters withconductivities below 20 µS (see separate brochure for details). 4E Conductivity MonitorSensor FeaturesHow a 4-Electrode Sensor Works4-Electrode Style Sensor: Allows the sensor to be usedover 0 to 2,000,000 µS range.PEEK® Sensor Construction: Electrode holders made ofPEEK®, a high performance thermoplastic that providesoutstanding mechanical strength and chemical resistance.High structural integrity ensures accurate conductivitymeasurement.Multiple Mounting Styles: Sensors available in 1" NPTconvertible-style, insertion-style, and 1-1/2" or 2" sanitarystyles. Titanium Electrodes: The four electrodes used in thesensor are made of titanium for greater chemicalresistance. Sensor Diagnostics: Sensor diagnostics are used to alarmthe user in the event of loss of sensor seal integrity orintegral temperature sensor failure. Automatic foulantrejection circuitry is used to compensate for the effects ofsensor fouling. As the two drive electrodes becomecoated by the process solution, a feedback mechanisminvolving the two sensing electrodes detects the decreasein drive potential and automatically re-establishes theproper drive potential. When the degree of coatingreaches a limit where compensation is no longer possible,the diagnostics actuate an alarm to signal that the sensorrequires cleaning.Multiple Sealing Materials: Multiple sealing materials areused to preserve sensor integrity over a wide range ofchemical processes and varying temperature.Q45C4 Conductivity monitors are designed to use a rugged 4-electrode sensor that provides wide-range conductivitymeasurement without the need for multiple sensors. Virtually allconductivity applications ranging from 0-200 µS up to 0-2,000,000µS (0-2 S) can be reliably measured using this unique and flexiblesystem. What can be accomplished with a single 4-electrode wouldnormally require at least three conventional 2-electrode sensorswith increasing cell constants. This “one sensor fits all” approach toconductivity measurement eliminates the need to inventorymultiple sensor types, as well as the confusion in matching cellconstants to conductivity ranges.The 4-electrode sensors not only provide wide rangemeasurement capability, but also excellent resistance to electrodecoatings that can degrade measurement accuracy. Changes inelectrode condition are compensated for in the electronictransmitter, so even partially fouled sensors continue to produceaccurate measurements. And should the sensor become so fouledthat it requires cleaning, the monitor will display a “fouled sensor”indication to ensure that operating personnel are alerted.Sensors for the Q45C4 system are available in a variety ofmounting configurations: convertible-style with 1" NPT threads forpipe or tank mounting, 1-1/2" or 2" sanitary-style fittings in 316stainless steel, and insertion-style for 1-1/4" NPT hot-tap assembliesthat allow the sensor to be removed from service without shuttingdown the process.In a traditional 2-electrode sensor, each electrode performs twofunctions. First, the electrodes are used to generate a “drivepotential” through the aqueous solution. Second, the electrodes areused to measure the level of current flow as the conductivity of thesolution varies. It is this dual role that limits a 2-electrode sensor toa narrow functional conductivity range.A 4-electrode sensor splits the two functions between two setsof electrodes. One set of electrodes is used to generate the drivepotential through the aqueous solution. The other set of electrodesis used to measure the current that flows between the two driveelectrodes. Because these two functions are separate, the 4-electrode sensor does not suffer the polarization effects that limit a2-electrode sensor to a narrow functional range. This allows a single4-electrode sensor to operate reliably over the entire 0-2 S/cmconductivity range.Benefits of a 4-Electrode Sensor 4E SensorsSuffix A - Power1 - 24 VDC, 2-wire (single output only)2 - 115 VAC with 2 relays3 - 230 VAC with 2 relays4 - Battery operated with two 0-2.5 VDC outputs5 - Battery operated with internal data-loggerSuffix B - Sensor Style 1 - Convertible-style, PEEK2 - Insertion-style, 316SS3 - 1-1/2" Sanitary-style, 316SS4 - 2" Sanitary-style, 316SS5 - Convertible, PEEK body with connectorSuffix C - Sensor Cable Length1 - 15 feet2 - 30 feet9 - Special OPTIONS:00-0048 Junction box 07-0100 NEMA 4X junction box31-0057 Sensor interconnect cable 07-0202 Submersion mounting hardware09-0046 Conductivity standard, 84 µS, 500 mL09-0047 Conductivity standard, 447 µS, 500 mL09-0048 Conductivity standard, 1,500 µS, 500 mL09-0049 Conductivity standard, 8,974 µS, 500 mL09-0050 Conductivity standard, 80,000 µS, 500 mL47-0005 2" U-bolt, 304SS05-0068 Panel mount bracket kitNotes 1. All sensor cable lengths greater than 30 feet require ajunction box (07-0100) and sensor interconnect cable (31-0057).2. PEEK sensor body is only available in convertible style.3. Pipe mount requires two 2" U-bolts (47-0005).4. Panel mount requires bracket (05-0068).Represented By:PDS-Q45C4 (08/10)Ordering Information:Model Q45C4-A-B-C Conductivity MonitorMonitor SpecificationsSensor SpecificationsMeasuring Range: 0 to 2,000,000 µS Wetted Materials: PEEK®, titanium, Viton®, EDPM316 Stainless Steel with sanitary orinsertion body stylesTemperature Compensation: Pt1000 RTDSensor Cable: 6 conductor plus 2 shields, HDPE jacketTemperature Range: -10 to 125°C (14 to 257ºF).Pressure Range: 0 to 100 psigMax. Flow Rate: 10 feet (3 meters) per secondMax. Sensor toAnalyzer Distance: 60 feet (18.3 meters) Sensor Body Options: 1" NPT convertible 1-1/4" insertion 1-1/2" or 2" sanitary-styleMain Display Range: 0.0 to 200.0, 0 to 2,000 µS;0.00 to 20.00, 0.0 to 200.0, 0 to2,000 mSRepeatability: 0.3% of span, or 0.1 µS, whichever isgreater Sensitivity: 0.05% of span or 0.1 µS, whicheveris greaterNon-linearity: 0.3% of span, or 0.1 µS, whichever isgreater Response Time: 6 seconds to 90% of step input atlowest setting Display: Large 4 digit main display, 0.75"characters. 12 digit alpha-numericsecond line displayPower: 16-35 VDC for loop-powered unit;115/230 VAC, 50/60 Hz., 10 VAmax.; 9 VDC for battery power Control Relays: Two SPDT relays, 6A @ 250 VAC, 5A@ 24 VDC, resistiveRelay Mode: Programmable for control or alarmfunctionAnalog Outputs: Isolated 4-20 mA, 550 ohm max.load. Two assignable 4-20 mA out-puts, 550 ohm max. (AC only)Data Logger: Battery version only, stores 32,000data pointsOperating Conditions: -20-60°C, 0-95% R.H. non-condensingEnclosure: NEMA 4X (IP-66) polycarbonatewall, panel, or pipe mount Weight: 2-wire or battery units: 1 lbs. (.45 Kg.)AC power units: 2 lbs. (.9 Kg)Analytical Technology, Inc.6 Iron Bridge DriveCollegeville, PA 19426Phone: 610/917-0991• Toll-Free: 800/959-0299Fax: 610/917-0992E-Mail: sales@analyticaltechnology.comAnalytical TechnologyUnit 1 and 2 Gatehead Business ParkDelph New Road, DelphSaddleworth OL3 5DEPhone: +44 (0) 1457 873 318Fax: +44 (0) 1457 874 468E-Mail: sales@atiuk.comWeb Site: www.analyticaltechnology.com