Vaisala PTB 200 A, Operating Manual

Page 1: ...Power connections 5 2 4 Serial output mode connections 6 2 5 Pulse output mode connections 7 2 6 Pressure connections 8 2 7 Multiple barometers on one RS 232C bus 9 3 SERIAL COMMANDS 10 3 1 General 10...

Page 2: ...ending mode SMODE STOP RUN and POLL modes address ADDR for POLL mode only defining single output command SCOM in STOP and RUN modes only sleep mode SLEEP list of software settings starting output R st...

Page 3: ...The serial output of the PTB 200 barometers can be used in continuous interval or on demand modes The pulse output is activated by an external trigger signal The PTB 200 digital barometers have two bu...

Page 4: ...ded mounting positions of the PTB 200 barometers are shown in Figure 1 27 5 1 08 120 4 72 65 2 56 6 5 0 26 104 4 09 139 5 5 49 145 5 71 133 5 24 120 4 72 Fig 1 Dimensions and mounting of PTB 200 barom...

Page 5: ...to a suitable length Pull back the braid and press it between the two brass disks of the cable bushing to make a full 360 degrees grounding see Fig 2 Then tighten the cable bushing to the barometer h...

Page 6: ...connections and jumpers However when a logic output is available in the host system a third wire can be connected to the power control terminal CTRL to enable external control of the barometer The POW...

Page 7: ...th the TXD line of the Intel 8051 microprocessor and the TTL INVERT output is in phase with the RS 232C output Although the PTB 200 barometers use a single polarity supply both positive and negative v...

Page 8: ...tions jumpers and push buttons The pulse output mode must be separately selected Two push buttons Fig 5 arrow up and arrow down are used to switch between the pulse output mode and the serial output m...

Page 9: ...th a standard Clippard barbed pressure fitting with 10 32 external thread installed in the barometer This fitting is ideal for an 1 8 internal diameter tubing If some other pressure fitting needs to b...

Page 10: ...and one common barometer receiving line and ground line see Figure 6 Each barometer must be initialized to POLL mode with a specific address 1 99 see ADDR SMODE POLL OPEN and CLOSE commands The host c...

Page 11: ...rial bus settings SERI echo on off ECHO output format FORM pressure resolution FORM units UNIT integration time MTIM FILT settling time response time MTIM FILT sending mode SMODE STOP RUN and POLL mod...

Page 12: ...ation of the PTB 200 barometers Command Comment starting output R stopping output S output single reading SEND address required in POLL mode setting output interval INTV control of a single barometer...

Page 13: ...are modified by the barometer N 7 1 N 7 2 E 8 2 E 8 1 O 8 2 O 8 1 Note N 7 2 works on software version 1 06 or higher only The following settings can not be used at all E 8 1 O 8 1 ECHO Setting the s...

Page 14: ...ed e g PPPP PP uuuu r n where PPPP PP pressure reading area uuuu pressure unit area r carriage return n line feed An example of changing the output pressure resolution from two to one decimal 0 01 0 1...

Page 15: ...liseconds The MTIM value can range from 4 to 255 The MTIM factory setting of the PTB 200 A is 64 this ensures a stable resolution of 0 01 hPa The integration time is then 64 x 25 ms 1600 ms The settli...

Page 16: ...ge into account is used SLOW mode introduces a multiplication factor of 16 to the integration time set with the MTIM command No derivative of the pressure change is taken into account The filter setti...

Page 17: ...meter starts to output pressure readings automatically after power up or reset The S command can be used to stop the output The POLL mode is used mainly during adjustment and calibration when several...

Page 18: ...ress 7 0 cr If the barometer is not in the POLL mode it will respond to any SEND command regardless of if there is an address or not See SMODE and SEND commands for further details SCOM Setting a user...

Page 19: ...arometer is ready to accept commands and execute them However because the barometer needs to wake up the time from a command to output is a bit longer in SLEEP mode than in normal mode List of basic s...

Page 20: ...S cr Command S ends the RUN mode SEND Output a single reading SEND cr STOP and RUN modes only SEND aa cr POLL mode only where aa the address of the barometer 0 99 SEND command is used to output one pr...

Page 21: ...eter OPEN and CLOSE commands are used to set a barometer momentar ily to STOP mode and back to POLL mode again This command is very useful when several barometers are connected to one RS 232C bus and...

Page 22: ...be given to invoke them ERRS Error message output ERRS cr ERRS command is used to print the error messages if any problems occur The command outputs an error code and error description ERRS cr E51 P...

Page 23: ...orter adjust ment or calibration periods e g two to four times a year can be chosen The user can not erase the basic pressure and temperature adjustment coefficients made at factory from the barometer...

Page 24: ...precalibration the multipoint corrections are entered through the serial interface see MPC and MPCI commands Note that up to 99 PTB 200 barometers can be connected to one RS 232C bus which makes thei...

Page 25: ...ultipoint correction on MPC OFF cr MPCI cr MPC ON cr The MPC MPCI commands are used in multipoint pressure adjustment at up to eight pressure levels If a new fine adjustment is needed the previous mul...

Page 26: ...n at each pressure level and enter the corrections using the MPCI commands MPCI cr 1 PTB reading 499 64 cr correction 0 024 cr 2 PTB reading 599 79 cr correction 0 013 cr 7 PTB reading 1100 33 cr corr...

Page 27: ...hPa a 0 2 hPa a Defined as the 2 standard deviation limits of end point non linearity hysteresis error or repeatability error Defined as 2 standard deviation limits of inaccuracy of the pri mary or w...

Page 28: ...mbar inHg mmHg torr psia Baud rates 300 600 1200 2400 4800 9600 Resolution PTB 200 A 0 01 hPa PTB 201 A 0 1 hPa Settling time after power up PTB 200 A 2 seconds PTB 201 A 1 second Pressure step respo...

Page 29: ...PTB 200 28 28 Digital Barometers SSD Operating Manual 24th February 1993 PTB200 O0284 1 1 Dimensions in mm inches 27 5 1 08 120 4 72 65 2 56 6 5 0 26 104 4 09 139 5 5 49 145 5 71 133 5 24 120 4 72...

Page 30: ...ending mode SMODE STOP RUN and POLL modes address ADDR for POLL mode only defining single output command SCOM in STOP and RUN modes only sleep mode SLEEP list of software settings starting output R st...