使用说明书手册DO7400

SensorexPRODUCT INSTRUCTION SHEETDissolved Oxygen Sensor Care and Use InstructionsProduct InstructionsIntroductionYour Dissolved Oxygen(DO)sensor is a galvanic electrochemi-FIG.1cal device;i.e.it does not require power from your meter orcontroller to generate its signal.The DO sensor will provide amillivolt signal proportional to the concentration of oxygenin the water(model DO7400,DO7400TC)or 4-20mA currentoutput(models DO7441 and DO7442).The signal outputis proportional to ppm of oxygen for probes with millivoltsignal output or changes linearly with ppm of oxygen sensorswith 4-20mA output.The partial pressure of oxygen,which isdirectly proportional to the percent saturation of oxygen in aspecified sample,can be calculated based upon the oxygensolubility which is a function of temperature,salinity,totalatmospheric pressure,etc.Your Dissolved Oxygen sensor consists of an cathode,anodeand an electrolyte separated from your process fluid by an oxy-gen permeable membrane.The oxygen passing through themembrane reacts at the cathode,giving up electrons,whichproduces an electrical current.Electrical ConnectionsFIG.2DO7400 and DO7400TC models:Red wire of Sensor to DO input +(cathode)Black wire of Sensor to DO input-(anode)White and Green wires of Sensor to Temperature input(10k NTC)(See wiring FIG 2)DO7441 and DO7442 models:COLORFUNCTIONRed wire of Sensor to DO input+(cathode)RREDCATHODEBlack wire of Sensor to DO input-(anode)BBLACKANODE(See wiring FIG3)WHTETEMPERATUREGetting Your DO Sensor Ready to UseGGREENTEMPE RATUREYour DO sensor is shipped to you dry and is not ready for use.Seesteps 1,7,8,9 and 10 of the "Sensor Reconditioning"section ofthis sheet for instructions on sensor preparation.The installedFIG.3Power Supply⊕sensorredwiremembrane shipped with the probe is usable if it passes thesensorleak test in step 8.Maintenance items included with your sen-black wiresor include:one each membrane lock tool,ywo each Teflon orHDPE membranes,two each membrane o-rings and 250mL ofelectrolyte.CalibrationPLC,DVMThe simplest method to calibrate your DO sensor is to holdit in air.You may also bubble air past the sensor in water.Thesensor is pre-calibrated at the factory (see Specifcations Sec-tion for calibration range).If you want a two-point calibration,a saturated solution of sodium sulfite(NazSO3)is suggested.17g Sodium sulfite in 125mL DI water is more than enough.Sodium sulfite will not reach a true zero output but it shouldreach less than 1 mV or less than 4.5mA in five minutes or less(See Specifications ection for range).Parts covered by this product data sheet include:D07400,D07400TCD07441,D07442Page 1 of 4Form:InstrD07400 [Rev:2011-03-24]2011 Sensorex Corporstion