Yokogawa 202 Field Mounting Rate Totalizer Manual do Utilizador

FIELD MOUNTEDRATE TOTALISERMODEL 202D1 February 1999

Specification62. SPECIFICATIONGeneralDisplay: LCD which is continuously powered.Resettable Total: 7 digits with 10mm (0.4") high digits. Resetta

Specification7DC Power/Alarm VersionOutputs: Two open collector outputs suitable for drivingDC solenoids or external relays. The outputs canbe progra

Operation83. OPERATIONThe Model 202D Rate Totaliser accepts a frequency or pulse input from a widerange of flowmeters. The instrument is fully progra

Operation93.2 TEST MODEThe 202D has a Test Mode which can be entered by simultaneously pressing all 3front panel keys. The tests are as follows:Low

Operation103.3 FILTERINGFrequency fluctuations caused by pulsating flow through a flowmeter can interferewith the precision of the rate. For this re

Operation11Filter Factor vs Time to Reach New Reading (for a step change in input signal) 0204060801001200 10 20 30 40 50 60 70 80 90 100Filter Factor

Operation123.4 CALCULATION OF RATE AND TOTALThe flow rate, R, is calculated as follows:where f is the input frequency in Hz (pulses/second).H is the

Operation133.5 TOTAL CONVERSIONThe Total Conversion Factor is programmed to enable the rate to be displayed inone engineering unit and the totals to

Operation143.6 FREQUENCY CUTOFFA frequency cutoff can be programmed below which flow rate is not registered.Input frequencies at or below the cutoff

Programming154. PROGRAMMINGThe Model 202D is fully programmable with all parameters being stored in non-volatile memory.The Program Mode can be entere

Programming164.1 PROGRAM STEPS Step CommentCAL 0 Pulse Output (applies to DC Power/Alarm version only).0 = No pulse output, low and high alarms.1 = S

Programming17 Step CommentCAL 6 Filter.The filter constant for filtering the input signal.1 No filtering.to99 Very heavy filtering.CAL 7 Decimal Point

Programming18 Step CommentCAL 12 High Alarm or Pulse Output Factor - whole numbers.CAL 13 High Alarm or Pulse Output Factor - digits after the decimal

Example195. EXAMPLEA flowmeter produces 20.538 pulses per litre and has a maximum outputfrequency on 200Hz. It is required to display the flow rate i

Versions206. VERSIONSThe following table summarises the features of each of the different versions ofthe Model 202D:Model Number 202D.X0 202D.X3 202D.

Versions216.1 BATTERY POWERED VERSIONThe battery powered version of the Model 202D is designed for operation in thefield without external power sourc

Versions226.2 DC POWER VERSIONThe DC power version will operate from an external power source between 9-28VDC and draws no more than 4mA. This enabl

Versions23Specification for Alarm OutputsMaximum Current (sink): 200mA.Maximum Voltage: 30Vdc.Saturation Voltage: 0.8Vdc across outputs when in the &q

Versions246.3 RELAY AND 4-20mA OUTPUT VERSIONThis version combines features of the DC powered with a 4-20mA output.The 4-20mA output provides a two-w

Versions25Typical ConnectionConnection to a Sensor requiring External Power

CONTENTS1. Introduction 11.1 Model Number Designation 31.2 Intrinsic Safety Considerations 42. Specification 63. Operation 83.1 Display 83.2 Test Mod

Flowmeter Input267. FLOWMETER INPUTThe Model 202D has an input conditioning circuit which will accept signals frommost pulse or frequency producing fl

Flowmeter Input27

Flowmeter Input281. Squarewave, CMOS or Pulse2. Open CollectorWith 15µA/150µA internal pull up current3. Reed Switch - Battery PoweredWith 15µA intern

Flowmeter Input294. Reed Switch - External DC PowerWith 150µA internal pull up currentNote: For a switch or reed input with contact bounce link DBH c

Flowmeter Input306. Namur Proximity SwitchNote: Use this connection for a DC powered version of the Model 202D.7. Namur Proximity Switch - External D

Intrinsic Safety Connections318. INTRINSIC SAFETY CONNECTIONSWhen installing the Model 202D in hazardous areas, the wiring and installationmust com

Intrinsic Safety Connections328.2 SIMPLE APPARATUSDevices such as reed switches which can be classed as "simple apparatus", asdefined in th

Intrinsic Safety Connections33

Intrinsic Safety Connections34

Intrinsic Safety Connections358.4 ALARM OUTPUTSThe low alarm and high alarm/pulse output can be connected to suitably certifieddevices providing the

9. Installation 379.1 Wall Mounting 379.2 Panel Mount Version 389.3 Removing the Front Panel 399.4 The Main Electronics 419.5 Wiring 429.6 Terminal

Intrinsic Safety Connections36

Installation379. INSTALLATION9.1 WALL MOUNTINGA wall mounting bracket is supplied with each instrument. Round head screwsshould be used to attach th

Installation389.2 PANEL MOUNT VERSIONThe panel mount version of the Model 202D is supplied with two panel mountbrackets and plug-in terminals which a

Installation399.3 REMOVING THE FRONT PANELThe front panel should be removed as follows:1. Remove the top and bottom cover strips (ie. the dark plasti

Installation40

Installation419.4 THE MAIN ELECTRONICSThe front section of the housing contains the microprocessor and display. It ispossible to adjust the display

Installation429.5 WIRINGWhen connecting the 202D it is good practice to use shielded cable. The shieldshould be connected to earth at one end of the

Installation439.6 TERMINAL DESIGNATIONSAll versions8 Pulse (+) / Coil Input7 Pulse (-) / Coil Input6 High Alarm (+) or Pulse Output (+) if installed5

Index44Index4-20mA Output, 24AAccumulated Total, 8Alarm Outputs, 35BBattery Powered, 21CCAL Sequences, 15Cutoff Frequency, 16DDC Power, 22Decimal Poin

Introduction11. INTRODUCTIONThe Model 202D Rate Totaliser is a microprocessor based instrument whichaccepts a frequency or pulse input from a wide ran

Introduction2♦ Unlike the previous Model 202, the 202D has an additional mounting option -it is available in a PANEL MOUNT version.The Model 202D Rate

Introduction31.1 MODEL NUMBER DESIGNATIONThe Model Number of the 202D describes the power & output options installedand the mounting options.Mode

Introduction41.2 INTRINSIC SAFETY CONSIDERATIONSThe Model 202D is certified for use in hazardous areas and has both CENELECand CSA NRTL/C approvals.T

Introduction5Relay OutputsThe outputs can be connected to IS circuits with the following maximumvalues:Ui = 28VIi = 93mAPi = 653mWThe internal capacit