Level Switch - BERTHOLD Italia Srl

Level SwitchMini-Switch LB 471P R O C E S S C O N T R O L

ApplicationThe BERTHOLD level switch is used in all branchesof industry, including the food industry. Thismeasurement system is applicable where one ormore alarm levels of liquids or bulk solids have tobe monitored. In fact, the BERTHOLD level switchis suitable for installation on all types of vessels orbunkers like storage tanks, hot-storage bunkers,vessels with agitators, high-pressure reactors, cyclonesor feeder chutes.Benefitscontactlessnno abrasionnmaintenance freenfail safenlong life timenno mechanical modificationsto the vessel requiredThe FunctionThe operation of the measuring system is based onthe application of the radiometric measuringprinciple, i.e. the physical law of absorption ofgamma radiation as it passes through matter.This measuring principle has been proved successfulon the most difficult applications for manyyears now.An arrangement of a level alarm switch is shownin picture 1. The shielded radiation source 1 is installedoutside the vessel at the height at which thealarm must be indicated. The radiation detector2 , is mounted at the same height on the oppositeside of the vessel. The detector signal istransmitted via a two-core standard cable to theevaluation unit 3 .Engineering dataDimensions of the vessel at themeasuring positionnThickness and density ofeach wall to be irradiatednDensity of the productto be measurednGas density under operating conditionsin high pressure systemsnMax. ambient temperatureoutside the vesselnDimensional drawings of agitatorsor other internals in the vesselnrequired Ex-proof class3Picture 1212

246135Evaluation Unit LB 4711 space saving, width only 4TE (0.8")2 3 LED’s for status control3 two line Display, illuminated4 easy data input using arrow keys5 easy calibration with the pushbutton "Cal"6 easily toggle to the measuring reading with the pushbutton "Clear"GM-DetectorEspecially for fluids with smooth surface, the GM Detector hits the spot. It is alsoapplicable for bulk material. For easy applications, it is the most cost-efficientalternative solution.For fast switching of 1,5 to 5s, or in order to reduce the source activity, the GMDetector is available with two counter tubes.NaI-DetectorFor bulk material which forms a cone it is essential to be able to adjust thethreshold very accurately. The NaI-Detector provides precise monitoring of thebulk cone diameter.Where high gas density is present in the vessel, the gamma radiation will beattenuated strongly even when the vessel is empty. Thus, the measuring differencebetween material and gas is smaller. The significantly more sensitiveNaI-Detector guarantees a reliable switching function in this situation.Super-SensAn even higher sensitivity is achieved by using a scintillator 150/150mm in theSuper- Sens. The integrated collimator ensures a good signal to noise ratio andreduces the background radiation interference.The Super-Sens is used where the NaI Detector is pushed to its limits.3

Evaluation Unit LB 471compact design for a 19" rack (3HE; 4TE)permanent self-monitoring by „watch dog timer“intrinsically safe detector connection (option)The diversity of applicable detectors results in the optimum solution for everyapplication.GM Detectorrelative sensitivity: 1Apply a GM Detector with counter tube for vessels:with diameter between approx. 1 to 5mwith typical wall thicknesses up to approx. 20mmNaI Detectorrelative sensitivity: 20Apply a NaI Detector instead of a GM Detector:to reduce the necessary source activityto keep the size of the shielding smallfor bulk cone measurementsfor high gas density in the vesselSuper-Sensrelative sensitivity: 65Apply the Super-Sens instead of a NaI Detector:for very thick wallsfor large vesselsif there is a demand for smallest source activitiesto continue using existing sources

Software-FunctionalityStandard-ModeIn order to reduce the time for commissioning, the menu "Standard-Mode" isavailable. It limits itself to the parameters for standard applications and offersthe following functions:automatic calculation of full count rate and time constantcalibration error indication by diagnostic routinepermanent error diagnosticProfessional-ModeIf you want to use additional functions, then you can switch to the "ProfessionalMode" any time and without interruption.The ”Professional Mode” offers:alternatively manual data entry for otherwise automatic calculated parametersautomatic compensation of the empty count rate for gas pressured vesselpassword protection, alternatively automatic protectiontimely notice and indication of an required source exchangemodification logerror logrelay multifunctionalstorage of a parameter set copy in the E²-Prom...Further applications from BERTHOLD TECHNOLOGIESDensityBulk FlowMoisture

Technical Data LB 471Evaluation Unit LB 4710TypesLB 4710-0XX for GM DetectorLB 4710-1XX for NaI Det. or Super-SensArrangements - In a 19" rack 3HE, 4TE, IP20max. 19 modules for 24Vmax. 18 modules for 115/230V- In a Cassette 3HE, 7TE, IP 20for any 19" rack- In a wall mounted housing, IP 66max. 3 modulesPower supply 18-30V DC or 24V AC +10% -15%option: 115/230V AC transformer+10% / -15%, 47-65HzPower consumption max. 4W per moduleOperating temp. -30 ... +60°C (243 ... 333 K)Storage temp -40 ... + 70°C (233 ... 343 K)keep dry!Weight0,3 kg per moduleDetector connection 2 wireoption: intrinsically safe [EEx ib] IICDigital Infor external emptyDigital Out1 relay for min./max. (SPDT)1 relay for failure signal1 relay for warning signalalternative as min./max. usablecontact load AC: max. 250V, max. 1A, max. 200VADC: max. 300V, max. 1A, max. 60Wohm resistive loadDisplay2 lines LCD illuminatedeach line 4 digitskeyboard for data entrykeyboard lockable via passwordTime constant 0,5 - 999sDecay compensation automatic, for Co-60 and Cs-137Timerbuffered with capacitorrunning period without power supply:approx. 1 MonthCertificatefor overcharging in vessels which areused for storage water-endanger fluidsaccording WHGSources and shielding according separate leafletModifications may occur without notice.GM DetectorsTypesSZ5-GHS-3171-1/2: with Ex-proofGHS-3172-1/2: without Ex-proofExplosion proof ATEX: II 2G EEx ib d IIC T6II 2G EEx de IIC T6CSA: Class I Div. 2 Group B,C,DClass II Div. 2 Group E,F,GHousing stainless steel, IP 65weight 4,5 kg for GHS 31726 kg for Sz5 GHS 3171Operating temp. -40 ... +50°C (233 ... 323 K)optional: water cooling jacketStorage temp. -40 ... +80°C (233 ... 353 K)Cable gland PG 16 for cable: Ø 5 ... 8mmCablee.g. LiYY 2x1,0 shieldedmaximum 1000m, maximum 40 OhmNaI DetectorsTypesLB 4401 .. with Ex-proofLB 5401 .. without Ex-proofscintillation counterwith NaI(Tl) crystal 50/50temperature stability : + / - 0,1%automatic drift compensationExplosion proof ATEX: II 2G EEx ib d IIC T6II 2G EEx de IIC T6II 2D IP 65 T 80°FM: Class I Div. 2 Group A,B,C,DClass II Div. 2 Group E,F,GHousing stainless steel, IP 65Weight6 kg without collimator18kg with collimatorOperating temp. -40 ... +60°C (233 ... 333 K)optional: water cooling jacketStorage temp. -40 ... +70°C (233 ... 343 K)Cable gland M 16 for cable: Ø 5 ... 10mmCablee.g. LiYY 2x1,0 shieldedmaximum 1000m, maximum 40 OhmSuper-SensTypesLB 4430 .. frontal irradiationLB 4431 .. radial irradiationscintillator 150/150temperature stability + / - 0,5%automatic drift compensationExplosion proof ATEX: II 2G EEx ib d IIC T6II 2G EEx de IIC T6II 2D IP 65 T 80°FM: Class I Div. 2 Group A,B,C,DClass II Div. 2 Group E,F,GHousing stainless steel, IP 65Weight54 kg up to 74 kg according designOperating temp. -40 ... +55°C (233 ... 333 K)optional: water cooling jacketStorage temp. -40 ... +70°C (233 ... 343 K)Cable gland M 16 for cable: Ø 5 ... 10mmCablee.g. LiYY 2x1,0 shieldedmaximum 1000m, maximum 40 OhmBERTHOLD TECHNOLOGIES GmbH & Co. KG · P.O. Box 100 163 · D-75323 Bad Wildbad, GermanyPhone +49 70 81-177-0 · Fax +49 70 81-177-100 · industry@BertholdTech.com · www.BertholdTech.comLB 471 · 05-2004.1000 · Id.No. 39505PR2 · Rev.02 · 05-2004