User manual VAISALA PTB200

[. . . ] SSD/Operating Manual PTB 200 Digital Barometers 24th February 1993 1 (28) PTB200-O0284-1. 1 PTB 200 DIGITAL BAROMETERS 1 PRODUCT DESCRIPTION 2 2 INSTALLATION 2. 1 2. 2 2. 3 2. 4 2. 5 2. 6 2. 7 Mounting Grounding Power connections Serial output mode connections Pulse output mode connections Pressure connections Multiple barometers on one RS 232C bus 3 3 4 5 6 7 8 9 3 SERIAL COMMANDS 3. 1 General 3. 2 Configuration commands 3. 3 Operating commands 10 10 11 19 4 ADJUSTMENT AND CALIBRATION 4. 1 Offset and gain adjustment 4. 2 Multipoint adjustment 22 23 24 5 TECHNICAL DATA 26 Appendix 1 Commands PTB200 Digital Barometer Appendix 1 SERIAL COMMANDS Function serial bus settings echo on/off output format pressure resolution units integration time settling time/response time sending mode address defining single output command sleep mode list of software settings starting output stopping output output single reading setting output interval control of a single barometer in POLL mode resetting error messages linear pressure adjustment multipoint correction Command SERI ECHO FORM FORM UNIT MTIM, FILT MTIM, FILT SMODE ADDR SCOM SLEEP ?R S SEND INTV OPEN , CLOSE RESET ERRS LP MPC, MPCI Comment STOP, RUN and POLL modes for POLL mode only in STOP and RUN modes only in POLL mode address required 1994-08-16 1 SSD/Operating Manual PTB 200 Digital Barometers 24th February 1993 2 (28) PTB200-O0284-1. 1 1 PRODUCT DESCRIPTION The PTB 200 A and PTB 201 A are fully compensated digital barometers designed to operate over a wide pressure and temperature range. The final factory adjustment and calibration of the PTB 200 A is done against a deadweight tester for best accuracy and pressure traceability. The PTB 201 A is adjusted and calibrated by using electronic working standards to meet the requirements of demanding weather station applications. [. . . ] Barometric pressure = \PPPP. PP\ \uuuu\\r\n<cr> Example of omitting the pressure unit from the output: >FORM<cr> "\PPPP. PP\ \uuuu\\r\n" ?\PPPP. PP\\r\n<cr> SSD/Operating Manual PTB 200 Digital Barometers 24th February 1993 14 (28) PTB200-O0284-1. 1 UNIT Setting the pressure unit UNIT x<cr> where x hPa*, kPa, mbar, inHg, mmHg, torr, psia (* factory setting). Example of changing the pressure unit to mbar: >UNIT mbar<cr> MTIM Setting the measurement time parameters MTIM<cr> The MTIM command is used to set the number of measurement samples (MTIM value) integrated to get a pressure reading. The MTIM factory setting of the PTB 200 A is 64; this ensures a stable resolution of 0. 01 hPa. The settling time including initialization and integration time is approximately 2 s. The MTIM factory setting of the PTB 201 A is 16; this ensures a stable resolution of 0. 1 hPa. The settling time including initialization and integration time is approximately 1 s. The MTIM value affects the settling time of the barometer: the longer the integration time, the longer the settling time. The FILT command also affects the integration and settling times (see FILT command). 150<cr> SSD/Operating Manual PTB 200 Digital Barometers 24th February 1993 15 (28) PTB200-O0284-1. 1 FILT Setting the filter parameters FILT xxx yyyy<cr> where xxx ON or OFF yyyy FAST or SLOW The FILT command is used to set additional numerical filtering modes. FAST mode introduces a multiplication factor of 4 to the integration time set with the MTIM command. In addition a special algorithm that takes the derivative of the pressure change into account is used. SLOW mode introduces a multiplication factor of 16 to the integration time set with the MTIM command. Example of setting the integration time to 5 seconds (MTIM 50, filter FAST): >MTIM<cr> Mtim : 64 ?filter : ON FAST Example of setting the integration time to 60 seconds (MTIM 150, filter SLOW): >MTIM<cr> Mtim : 50 ?Then only the MTIM command affects the integration and settling times. SSD/Operating Manual PTB 200 Digital Barometers 24th February 1993 16 (28) PTB200-O0284-1. 1 SMODE Setting the sending mode STOP and RUN modes only POLL mode only SMODE xxxx<cr> SMODE aa STOP<cr> where xxxx STOP, RUN or POLL aa the address (1. . . 99) of the barometer in the POLL mode SMODE command sets or inspects the sending mode of the barometer. After power-up or reset the barometer outputs only its type code and software version number; pressure readings are output only by command. In the RUN mode the barometer starts to output pressure readings automatically after power-up or reset. The POLL mode is used mainly during adjustment and calibration when several barometers are connected to one RS 232C bus. In the POLL mode measurements can be output only with SEND aa command (see SEND aa command). See also OPEN and CLOSE commands for further details on how to control a single barometer when several barometers are connected on one RS 232C bus. Example of setting, using and resetting the POLL mode: >SMODE<cr> Serial mode : STOP >ADDR<cr> Address : 0 ? [. . . ] Note that up to 99 PTB 200 barometers can be connected to one RS 232C bus which makes their adjustment and calibration more cost effective. 4. 1 Offset and gain adjustment LP Linear pressure adjustments LP<cr> The LP command is used in offset and offset/gain adjustment of the barometer. To guarantee the best possible pressure stability connect the pressure port of the barometer to the pressure standard even during offset adjustment. The two pressure levels used in offset/gain adjustment must be at least 400 hPa apart. (set pressure level and enter value here)<cr> P : (the current non-corrected value appears here) Ref2 ? [. . . ]