Setra-system Model 470 Manual de usuario

1Model 470Digital Pressure Transducers

10ASCIIFunction Command ASCII Hex Name Code Code Code Description SectionUSER xUx * * Enter conversion ratio for 4.3DEFIN

113.5 In Case of Error MessagesThe following summary explains the meaning of error messages that you may receive from the470 in response to a command,

123.6 SymbolsThe following summary explains the meaning of symbols that may follow the data you receivefrom the 470 in response to a command.“OK” The

13SECTION FOURPrecision Measurement Functions4.1 InterrogationThe most commonly used function of the Setra 470 is the PRINT or INTERROGATION command.T

143. The transducer deselects the engineering units currently in use, and selects the nextengineering units in the sequence:hPa hectopascalsPSI pounds

159. If the response “NO CAL” is received, the program enable switch specified in Step 5 isnot set to “ON”. Transmit C, for CLEAR, and restart this p

169. If the 470 responds “UNABLE”, the user defined units have been disabled by use of theDISABLE UNITS function (Selection 5.3). Transmit C, for CLE

175. Transmit the new low setpoint, followed by S.6. The 470 responds “PROTEC”. Set the program enable switch to “OFF”(Section 7.2). Transmit C, for

18For example, to subtract 10 from the reading, transmit:10Z3. To add an offset to the reading, transmit -, the minus sign, followed by the amount of

192. The transducer reports a sequence of information which indicates the status of anyfunctions which are currently in use and some blank lines, as s

2ContentsSECTION ONE: Introduction ... 31.1 About th

204. Transmit S, for SETUP.5. If the elevation was in meters, transmit U, for CONVERT.6. Transmit S, for SETUP.For example, if the station elevation i

21SECTION FIVESetup Functions5.1 Status After Power is AppliedThe Setra 470 has an internal nonvolatile memory for storing certain status and calibrat

222. Transmit -5555S. This is the baud rate access code.3. Transmit the new baud rate. The Setra 470 supports 300, 600, 1200,2400, 4800, or 9600 bau

235. Transmit a sequence of 1’s and 0’s in which each 1 or 0 corresponds to an engineeringunit of measure in the sequence listed below. Transmit a 1

243. Transmit a sequence of 1’s and 0’s in which each 1 or 0 corresponds to an engineeringunit of measure in the sequence listed below. Transmit a 1

258. Transmit C, for CLEAR.9. The Setra 470 next reports the VERIFY message described in Section 5.7 and executesthe internal start-up procedure for t

26To change the Stability Indicator Limit, use the following procedure:1. Use the CONVERT function (see Section 4.2) so that the 470 reports data in u

27SECTION SIXAltitude Measurement FunctionsThe Setra 470 Digital Pressure Transducer can report a variety of altitude measurements. It may be usedas

28altitude in response to an interrogation as it is moved from one location toanother.CAUTION: In any true altimetry application, the accuracy of the

296.3 Relative Altitude MeasurementThe Setra 470 can measure relative altitude in either Standard or True Altimeter Mode. In thismode, the 470 report

3 SETRAModel 470Digital Pressure TransducerSECTION ONEIntroduction1.1 About the Setra 470The Setra 470 Digital Pressure Transducer is a highly accurat

30SECTION SEVENCalibration7.1 CalibrationThe zero and span of the Setra 470 Digital Pressure Transducer may be calibrated using theprocedures in Secti

317.3 Zero CalibrationThis procedure for recalibrating the zero point of the transducer can be aborted at any point bysetting the program enable switc

327.4 Span CalibrationTo perform the span calibration on the 470, it is necessary to apply both the zero and the fullscale pressures, as described in

33Appendix IInterface Program ExampleFollowing is an example of interfacing the Setra 470 to an IBM or compatible PC (PersonalComputer). Although rea

34SpecificationsPressure media: Clean dry nonconductive noncorrosive gasAccuracy:accuracy1±0.02% full scale at 70°F (21°C)nonlinearity ±0.012% full sc

35Limited WarrantySETRA warrants its products to be free from defects in materials and workmanship, subject to the folloingterms and conditions: With

41.2 About this ManualThis manual contains information you need to use the Setra 470. Whenever possible, theinformation is presented in nontechnical

5SECTION TWOInstalling the Model 4702.1 Power ConnectionsThe Setra 470 requires a 5 volt DC power supply regulated to ±1% which can supply 90 milliamp

6If it does not, (i.e. if the computer also has a DTE interface, and therefore transmits on its own pin2, and receives on its own pin 3), a “reversing

7SECTION THREECommunications Interfacing3.1 Communications Software ProtocolsThe Setra 470 RS-232 communication port allows several rates of data tran

83.4 FunctionsThis summary of functions is provided for reference only. See the following sections for details onhow to use each function. Command c

9— — 45 $2D Shuts off thefunction whosecommand code follows it.— CLEAR —C 45 67 $2D $43 Turn off MIN/MAX, clear 3.3the tare value, convert to theorigi