Remote Technologies RPC-320 manual Measuring Higher Voltages, Data logging on a timer tick

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ANALOG INPUT

The outpu t voltage fro m the tem peratur e sensor is doubled by jumpering H1[5-7]. While this does not change the range the unit operates at, it does change increase temperature m easurement sensitivity.

Data logging on a timer tick

Some applications require that data is read at fixed intervals. The O NTI CK con struct is used to take data in intervals from 0. 01 to 327 seconds. The exam ple below takes 1 sample per second until 100 samples have been obtained.

10 DIM A(100)

20 ONTICK 1,500

30 REM THE REST OF YOUR PROGRAM

40 REM CONTINUES

80 GOTO 30

500 A(N) = AIN(3)

510 N=N+1

520 IF N = 100 THEN ONTICK 0,500

530 RETI

MEASURING HIGHER VOLTAGES

Voltages higher than + 5V are measur ed by inserting a series r esistor to the inp ut.

The table below shows resistor values for some input voltages using the 0-5V range.

Maximum

Input Voltage Resistor

620K

12.5150K

24380K

Use the following formula to determine the series resistance necessar y for a m aximum voltage input:

Rs =	Vi * 20000 - 100000	0 - 5V range
Rs =	Vi * 40000 - 100000	0 - 2.5V r ange

Rs is the re sistor value in ohms in ser ies with the inpu t. Vi is the maximum input voltage. W hen Rs is negative or zero, a series resistor is not necessary.

A high Rs v alue can ca use noisy r eadings. This is because the resistor acts as an antenna. To reduce noise, place a 0.1 mfd to 1 mfd capacitor betw een the input terminal and ground.

NOTE: When an input voltage exceeds the input range, other channel values are affected.

SECTION 10

Page 10-5 RPC -320

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Contents Trademarks REVRevision Table of Contents Sect ION 11 Watchdog Timer Description External ResetInterrupt Characteristics Sect ION 13 Multi Mode Counter DescriptionSoftware Revision History Overview SectionDescription Manual OrganizationSymbols and Term inology Technical SupportOverview Section System layoutIntroduction Operating PrecautionsEquipment Using a PC Using a TerminalFirst Time Operation Uploading and Downloading ProgramsEditing programs and program ming hints Where to GO from Here TroubleshootingSaving Programs Saving a ProgramEprom W3 autorun jumperAutorunning Preventing AutorunLoading a Program Changing Eprom SizeCommands Alternate EpromsBload BsaveCOM0 Serial Port Serial PortsCOM1 Serial Port RS-422/485 Operating Information Serial Ports SectionRS-422/485 Termination network Two wire RS-485 Accessing Serial BuffersMultidrop Network Disabling CONTROL-C Accessing COM0 and COM1Serial Port PIN OUT RXD CTS Battery Backup Checking the batteryRAM Memory Changing MemoryReserved Memory Storing Variables in RAMAssembly Language Interface Block Data TransferDigital I/O Ports Digital and Opto PortsDigital Por t J3 Digital I/O Commands Digital Port P6High Current Port L8 Optically Isolated InputHigh Current Output Interfacing Digital I/O to an opto-module rack Interfacing to switches and other devicesDigital I/ O prog ramm ing exam ple Ls e Width Modulation PWM Digital and Opto Ports Section Conne ctor pin ou t J3Config Line CountLine Line BDate Setting Date and TimeM E Section Writing to the Display Connecting DisplaysProgramming Example Display Connector PIN OUT Display TypesKeypad Port Program explanationKeypad Port PIN OUT J5 Connecting Analog Inputs Analog InputInitialization Overvoltage conditionsExamples u sing CON FIG AIN Differential ModeAcquiring Analog Data Temperature Measurement Noise NotesAnalog Input Section Data logging on a timer tick Measuring Higher VoltagesAmplifiers Converting Analog MeasurementsMeasuring 4-20 mA current loops Calibration Watchdog Timer External ResetOptically Isolated Interrupt Interrupt CharacteristicsProgram Example Optically isolated and TTL interrup ts Programming GNDLoad GateCOU NT0 Power Management Further Power ReductionPower Management Section Program Examp leElectrical Specifications Technical InformationMechanical Specifications Memory and I/O Bank MAPJumper Descriptions Bank